Crocodilia
Crocodylus acutus acutus Cuvier
Crocodylus acutus Cuvier, Ann. Mus. Hist. Nat. Paris, 10:55, 1807.—Santo Domingo.
Crocodylus acutus acutus, Müller and Hellmich, Ibero-Amerik. Stud., 13:128, 1940.
Boca de Apiza (2); Playa Azul (2).
The crocodile or "caiman" is abundant in the brackish lagoons along the cost of Michoacán; three large adults and several juveniles were observed at Estero Pichi at Playa Azul; others were seen at Mexiquillo and Maruata. Residents of the Balsas-Tepalcatepec Basin frequently have reported "caimanes" in the Río Balsas and Río Tepalcatepec, but the existence of the crocodile in these rivers has not been verified by specimens.
Sauria
Phyllodactylus duellmani Dixon
Phyllodactylus duellmani Dixon, Southwest Nat., 5:37, April 15, 1960.—Rancho El Espinal, Michoacán, México.
Fourteen km. SSW of Apatzingán; Capirio; Cafradía (3); El Espinal (3).
This species is known only from the Tepalcatepec Valley, where it has been found in open arid situations from 180 to 500 meters. Specimens were found in the daytime in stumps, dead cacti, and the hollow branches of the legume, Apoplanesia paniculata. In life adults were pale gray or grayish tan above and creamy white below. A juvenile having a snout-vent length of 18 mm. had a pale orange tail with gray cross-bands. In the adults the tail was colored like the body. The specimen from 14 kilometers south-southwest of Apatzingán (KU 29764) and those from Cofradía (BMNH 1914.1.28.28-30) were not listed by Dixon (1960).
Phyllodactylus homolepidurus Smith
Phyllodactylus homolepidurus Smith, Univ. Kansas Sci. Bull., 22:121, November 15, 1935.—Five miles southwest of Hermosillo, Sonora, México.
El Ticuiz (2); La Placita; Ostula (2); Pómaro; San Pedro Naranjestila.
These specimens have been referred to Phyllodactylus homolepidurus by James R. Dixon (in litt.), who is currently studying the American members of the genus. Geckos of this species have been found in tropical semi-deciduous forest in the coastal lowlands to elevations of 500 meters. Most specimens were found beneath the bark of standing dead trees or stumps. Two individuals from El Ticuiz (UMMZ 115102) in life were dark gray above with brownish tubercles; the belly was a dusty cream-color. Apparently this species does not enter the Tepalcatepec Valley, where Phyllodactylus lanei is abundant.
Phyllodactylus lanei Smith
Phyllodactylus lanei Smith, Univ. Kansas Sci. Bull., 22:125, November 15, 1935.—Tierra Colorado, Guerrero, México.
Apatzingán (13); 21 km. S of Arteaga: El Sabino (53); La Playa; Ostula (2); Río Marquez, 10 km. S of Lombardia (8); 16 km. N of Tafetán.
This widespread species has been taken at elevations of less than 1100 meters in the Balsas-Tepalcatepec Basin, where it occurs in riparian situations in the foothills. Specimens have been collected in tropical semi-deciduous forest at Ostula and in oak forest south of Arteaga; both of these localities are on the Pacific slopes of the Sierra de Coalcomán, a region inhabited by Phyllodactylus homolepidurus. Both species have been collected at Ostula.
A juvenile from 21 kilometers south of Arteaga (UMMZ 118933) had alternating black and white bands on the tail. In life most of the lizards are dull ashy gray or grayish tan above and white below. According to Dixon (in litt.), one specimen from Apatzingán (UMMZ 115102) resembles Phyllodactylus magnus in scutellation, but it lacks the distinctive yellow venter of that species.
Apparently Phyllodactylus lanei is restricted to rather mesic environments in the Balsas-Tepalcatepec Valley and surrounding foothills; in the more open arid environments on the floor of the valley it seems to be replaced by Phyllodactylus duellmani.
Phyllodactylus paucituberculatus Dixon
Phyllodactylus paucituberculatus Dixon, Southwest. Nat., 5:40, April 15, 1960.—Río Cupatitzio (= Río Marquez), 6.5 miles south of Lombardia, Michoacán, México.
Río Marquez, 10 km. S of Lombardia (6).
Two of these specimens (UMMZ 112692-3) were discussed in detail by Dixon (1960:40) in his description of the species. On August 25, 1960, Dixon collected four additional specimens at the type locality, a conglomerate cliff along the Río Marquez. These will be reported by him in his forthcoming study of the genus.
Anolis dunni Smith
Anolis dunni Smith, Copeia, no. 1:9, May 10, 1936.—Agua del Obispo, Guerrero, México.
Arteaga (3); 19 km. S of Arteaga.
Three females from Arteaga (UMMZ 119075) have snout-vent lengths of 41, 41, and 44 mm. In life the pale grayish brown dorsum was marked with dark brown; the belly was white, and the throat was pale pink. All have a dark interorbital bar and dark vertical bars on the upper labials. In two specimens there are only scattered dark flecks on the dorsum; in the third there is a dark postorbital stripe, a dark lateral stripe, and four narrow transverse bands on the body. A male from 19 kilometers south of Arteaga (UMMZ 119076) having a snout-vent length of 49 mm. had in life a tan dorsum, a broad white stripe from the ear to the groin, scattered small white spots on the dorsum, and indistinct pale cream-colored spots on the posterior surfaces of the thighs. This male has the dark labial bars, but lacks the dark interorbital bar, found in the females. The large rose-pink throat fan extends to about the middle of the belly. In all of the specimens the middorsal scales are keeled and much smaller than the smooth pavementlike or slightly imbricate ventrals. All have two gulars in contact with the mental, five scales between the nasals, five scales (not including the first labials) in contact with the rostral, and four rows of loreals. In these characters these specimens agree well with Anolis dunni from Guerrero, as diagnosed by Davis (1954b).
Previously Anolis dunni has been reported only from the vicinity of Agua del Obispo, Guerrero, a locality situated at an elevation of about 900 meters in pine-oak forest in the Sierra del Sur. All known close relatives of Anolis dunni occur only in Guerrero: A. taylori Smith and Spieler from Acapulco, A. gadowi Boulenger from Tierra Colorado, A. liogaster Boulenger, and A. omiltemanus Davis from Omiltemi. The present specimens from elevations of about 900 meters in riparian stream vegetation and oak forest represent the northern known limits of this group of Anolis.
Anolis nebulosus (Wiegmann)
Dactyloa nebulosa Wiegmann, Herpetologia Mexicana, p. 47, 1834.—México. Type locality restricted to Mazatlán, Sinaloa, México, by Smith and Taylor (1950b:66).
Anolis nebulosas, Bocourt, Mission Scientifique au Mexique et dan l'Amerique Centrale. Reptiles, livr. 2:77, 1873.
Acahuato (3); Agua Cerca; Apatzingán (4); Araparicuaro (3); 29 km. S of Ario de Rosales (3); 20 km. S of Arteaga (2); Barranca de Bejuco; Cascada Tzararacua (5); Cerro Tancítaro (13); Cherán; Chupio (5); Coalcomán (10); Cofradía; Dos Aguas (10); 18 km. E of Dos Aguas (3); El Diezmo; El Sabino (43); El Ticuiz; Jiquilpan (2); La Orilla; La Placita; La Playa (3); Los Conejos (2); Los Pozos; Nogueleras (2); Ostula; 8 km. W of Pátzcuaro (2); 8 km. NE of Pátzcuaro; Playa Azul (3); Río Cachán; Río Marquez, 10 km. S of Lombardia; Río Tepalcatepec, 27 km. S of Apatzingán; San Juan de Lima (6); San Pedro Naranjestila; Temazcal; Tuxpan (2); Tzitzio; Uruapan (74); 11 km. N of Uruapan (2); Volcán Jorullo; 16 km. E of Zacapu (2); 18 km. W of Zamora; Ziracuaretiro.
Even with the abundance of material the assignment of a specific name to these anoles is only tentative, for definite determination between Anolis nebulosus Wiegmann and A. nebuloides Bocourt is uncertain. Bocourt (1873:75) distinguished A. nebuloides from A. nebulosus by the following characters: (1) head scales keeled, not smooth; (2) snout narrower; (3) ear opening larger; (4) supraorbital semicircles separated by a row of small scales and not in contact; (5) dorsal scales larger and subequal in size to the belly scales. Boulenger (1885:77) used the same characters; Smith and Taylor (1950b:58) in their key to the Mexican species of Anolis stated that the dorsal scales are slightly smaller than the ventrals in A. nebulosus and markedly smaller in A. nebuloides. Smith (in litt.) stated that the characters of the relative sizes of the dorsal and ventral scales were incorrect in that key.
The application of the above criteria to specimens from Michoacán has not resulted in the recognition of two species. The majority of the specimens have the supraorbital semicircles separated by at least one small scale; the head scales, with the exception of those on the snout in a few individuals, are smooth; the dorsal scales are only slightly smaller than the ventrals. In other characters of scutellation the specimens are highly variable. The males in life have an orange throat fan. Anoles of this kind have been found in Michoacán, Colima, Jalisco, Nayarit, and southern Sinaloa. Near Oaxaca, Oaxaca, specimens were collected that superficially resemble those from Michoacán and farther north. These have low keels on the snout scales, dorsals somewhat larger than the ventrals, and a pink throat fan. In ten males from Oaxaca the size of the dorsal scales relative to that of the ventrals is 1.00:0.83; the same ratio for 25 males from Michoacán is 1.00:1.08. In both samples there are specimens in which the dorsal and ventral scales are about equal in size.
Investigations by Richard E. Etheridge on the osteology of Anolis, including those species here being considered, have revealed relatively constant differences in the parasternalia and in the caudal vertebrae. The application of Etheridge's findings to anoline systematics must await the completion of his study.
The carination of the scales on the snout versus smooth scales there seems to be the only significant character given by Bocourt that distinguishes A. Nebuloides from A. nebulosus. The difference in the color of the throat fan, which is apparent only in living individuals, is more striking. Obviously more than one species is represented, as is borne out by the differences in the color of the throat fan and in the osteology, but there is uncertainty about the correct name for each species. On the strength of Bocourt's diagnosis of keeled snout scales in A. nebuloides, I am applying that name to the population in Oaxaca and A. nebulosus to the specimens from Michoacán. As arranged here, the two species can be distinguished, as follows:
A. nebulosus.—Dorsal scales only slightly smaller than the ventral scales; snout scales usually smooth; throat-fan bright orange in adult males.
A. nebuloides.—Dorsal scales somewhat larger than the ventral scales; snout scales having a low keel; throat-fan pink in adult males.
With respect to geographic distribution, A. nebulosus has been collected from southern Sinaloa southward to Michoacán. The lizards here referred to A. nebuloides have been taken only in pine-oak forest on the mountain slopes near Oaxaca City. Zweifel and Norris (1955:233) reported anoles with pink throat-fans from southern Sonora; possibly those specimens are A. nebuloides; I have not examined them. I have seen several preserved specimens from the vicinity of Tehuantepec, Oaxaca. Although they probably belong to this group, those specimens differ from both A. nebulosus and A. nebuloides in their larger size, relatively larger head, and much larger throat fan.
Aside from the minor variation in scutellation, specimens of Anolis nebulosus from Michoacán vary greatly in coloration. Usually the females have some form of a broad middorsal pale-colored band. In life this is dull yellow, tan, or orange. Two females from Dos Aguas are strikingly different; one (UMMZ 119521) has a broad middorsal orange stripe that is scalloped laterally and bordered by gray. The other (UMMZ 119081) has a narrow middorsal cream-colored line. Males usually are unicolor brown or olive-tan; sometimes the middorsal region is darker. Some individuals have dark cross-bands or chevrons on the dorsum. One male from Dos Aguas (UMMZ 119080) has a cream-colored lateral stripe.
In Michoacán Anolis nebulosus occurs from sea level to elevations slightly in excess of 2100 meters, usually in areas of dense cover, whether this be herbaceous, viney, or woody, ordinarily on the ground as well as in bushes and trees. One was in a bromeliad growing about ten meters above the ground. In the arid Tepalcatepec Valley anoles of this species are most frequently found in the tangled growth along streams. Above Uruapan they were found in pine-oak forest, and on the Mexican Plateau between Zamora and Zacapu they were found in a bunch grass-scrub oak association.
Anolis schmidti Smith
Anolis schmidti Smith, Publ. Field Mus. Nat. Hist., zool. ser., 24:21, January 30, 1939.—Manzanillo, Colima, México.
La Placita; San Juan de Lima.
Peters (1954:11) reported on the specimen from La Placita; another was secured at San Juan de Lima in 1956. The latter (UMMZ 115078) is a male having a snout-vent length of 43.0 mm. and a tail length of 70.5 mm. The dorsal ground color is pale tan; there are five pairs of irregular dark brown dorsolateral blotches. In life the throat fan was pale orange. These specimens agree with those from Colima described by Duellman (1958c:10). The distribution of Anolis schmidti seems to be restricted to the coastal lowlands from Michoacán to Nayarit.
Basiliscus vittatus Wiegmann
Basiliscus vittatus Wiegmann, Isis von Oken, 21:373, 1828.—México. Type locality restricted to Veracruz, Veracruz, México, by Smith and Taylor (1950b:72).
Apatzingán (9); Capirio; Coahuayana (5); El Cerrito; El Sabino (2); El Ticuiz; La Placita (3); Maruata (2); Motín del Oro; Ostula; Playa Azul (3).
This species has been found only on the coast and in the low Tepalcatepec Valley. In the latter area it is restricted to riparian situations along the larger streams. The lizard is abundant in the mangrove swamps bordering the brackish lagoons on the coast. In July, 1955, scores of individuals were seen around Estero Pichi at Playa Azul. Adults, especially the large males, are exceedingly wary and difficult to collect. At all localities where they were found, the lizards were most often seen in dense bushes, where they are well camouflaged. Individuals of all sizes were observed to run across the surface of the ponds.
Iguana iguana rhinolopha Wiegmann
Iguana rhinolopha Wiegmann, Herpetologia Mexicana, p. 44, 1834.—México. Type locality restricted to Córdoba, Veracruz, México, by Smith and Taylor (1950b:72).
Iguana iguana rhinolopha, Van Denburgh, Proc. Acad. Nat. Sci. Philadelphia, 1897:461, January 18, 1898.
Apatzingán (8); Capirio (3); El Cerrito; El Ticuiz (2); La Placita; La Playa (2); Maruata; Playa Azul; Río Cachán.
Like the preceding species, this lizard is always found near water. It does not ascend the foothills of the Sierra de Coalcomán, but in the Balsas Basin it reaches elevations of 800 meters at La Playa. Large adults are often seen in the large trees making up the gallery forests along rivers. From high perches the lizards drop into the water with a terrific splash. Bright green juveniles were abundant in bushes along the Río Tepalcatepec in July, 1955.
Ctenosaura pectinata (Wiegmann)
Cyclura pectinata Wiegmann, Herpetologia Mexicana, p. 42, 1834.—México (by inference). Type locality restricted to Colima, Colima, México, by Bailey (1928:25).
Ctenosaura pectinata, Gray, Catalogue of the lizards... British Museum, p. 191, 1845.
Apatzingán (27); between Ario de Rosales and La Playa; Barranca de Bejuco; Capirio (2); Coalcomán (4); El Espinal; El Sabino (2); El Ticuiz; Jazmin (2); La Huacana; La Placita (8); La Playa (3); Limoncito; Lombardia; Motín del Oro; Playa Azul; Río Cancita, 12 km. E of Apatzingán (2); Río Marquez, 10 km. S of Lombardia (2);? Uruapan; Volcán Jorullo.
Ctenosaura pectinata is a common lowland species that ascends the slopes of the Sierra de Coalcomán and the Cordillera Volcánica to elevations of about 1050 meters (approximating the lower limits of the oak forest). The record from Uruapan (USNM 10234, collected by Dugès) is doubtful.
These large lizards are most easily observed on rock fences along roads. Near Apatzingán innumerable individuals can be seen in mid-morning. Later in the day, as the sun rises higher in the sky, the lizards retreat to the shade of the crevices in the fences. The abundance of these lizards in the Tepalcatepec Valley, together with evidence gathered from the natives of the valley, indicates that these lizards are seldom used for human consumption there. On the other hand, several people in Coalcomán consider the "iguana negra" (local name for Ctenosaura) to be a delicacy and serve it at every opportunity. In early July, 1951, brilliant green young of the year were collected at La Playa and at Coalcomán.
Enyaliosaurus clarki (Bailey)
Ctenosaura clarki Bailey, Proc. U. S. Natl. Mus., 73:44, September 26, 1928.—Ovopeo (= Oropeo), Michoacán, México.
Enyaliosaurus clarki, Duellman and Duellman, Occ. Pap. Mus. Zool. Univ. Michigan, 598:1, February 16, 1959.
Twelve km. SSW of Apatzingán; Capirio (7); Cofradía (3); El Espinal (2); 32 km. E of Huetamo; Jazmin (5); Oropeo (10); Rancho Nuevo; Río Cancita, 12 km. E of Apatzingán (8); Tepalcatepec (3); Zicuiran (6).
This species is known only from the low areas of the Balsas-Tepalcatepec Basin between elevations of 200 and 510 meters. It is commonly found in the open arid tropical scrub forest dominated by Prosopsis sp., Apoplanesia paniculata, and Cercidium plurifoliolatum. Continued collecting in the Tepalcatepec Valley has borne out the suggestions of Duellman and Duellman (1959) concerning the distribution and abundance of this lizard. Also, continued collecting in Colima and on the Pacific coast has failed to reveal the presence of Enyaliosaurus there.
Phrynosoma asio Cope
Phrynosoma asio Cope, Proc. Acad. Nat. Sci. Philadelphia, 16:178, September 30, 1864.—Colima, Colima, México.
Apatzingán (4); San Salvador.
In Michoacán this species has been obtained only in the Tepalcatepec Valley and on the northern slopes of the Sierra de Coalcomán between 300 and 700 meters. Apparently the lizard is absent from the coastal lowlands of Michoacán and Guerrero. The distribution of this species, therefore, is discontinuous. One population inhabits the lowlands of Colima and the Balsas-Tepalcatepec Basin inland to northern Guerrero and Morelos; a southern population inhabits the Plains of Tehuantepec in Oaxaca.
A juvenile from Apatzingán (USNM 47739) has a snout-vent length of 40.0 mm. and a tail length of 19.5 mm.
Sceloporus aeneus aeneus Wiegmann
Sceloporus aeneus Wiegmann, Isis von Oken, 21:370, 1828.—México. Type locality restricted to Tres Cumbres, Morelos, México, by Smith and Taylor (1950b:137).
Sceloporus aeneus aeneus, Smith, Occ. Pap. Mus. Zool. Univ. Michigan, 361:6, December 15, 1937.
Angahuan; Araparicuaro (2); Capácuaro (2); Carapan (11); Cherán (11); 18 km. WNW of Ciudad Hidalgo (10); Cuseño Station; Jeráhuaro; Los Conejos (36); Macho de Agua (7); Opopeo; Paracho (2); Pátzcuaro (4); Pino Gordo; 18 km. W of Quiroga (2); Tancítaro (49); Uruapan (14); 16 km. NW of Zacapu (5); between Zacapu and Zamora (2); 13 km. E of Zinapécuaro; 14 km. SE of Zitácuaro (14).
This small terrestrial species inhabits the pine and fir forests of the Cordillera Volcánica between elevations of 1850 and 3100 meters; apparently it is absent from the Sierra de Coalcomán. It seems to prefer rather open coniferous forests in which there is a more or less continuous cover of grasses on the ground. On warm sunny days the lizards can be observed scurrying about in the grass; in the early hours of the day, or on cold days, they are found beneath stones, logs, or dead clumps of bunch grass.
Sceloporus asper Boulenger
Sceloporus asper Boulenger, Proc. Zool. Soc. London, 1897:497, October, 1897.—La Cumbre de los Arrastrados, Jalisco, México.
Apatzingán (3); 10 km. E of Dos Aguas; Uruapan (41).
This strictly arboreal lizard is abundant in the mixed broad-leafed forest near Uruapan. The lizards are exceedingly wary and can be approached only with difficulty. In life males have pale blue bellies; the throat is pale pink. The pale gray dorsum marked with irregular darker gray blotches blends well with the color of the tree trunks on which the lizard lives. The one specimen from Dos Aguas was found on a pine tree; it provides the only record for the species from the Sierra de Coalcomán.
Sceloporus bulleri Boulenger
Sceloporus bulleri Boulenger, Proc. Zool. Soc. London, 1894:729, April, 1895.—Las Cumbre de los Arrastrados, Jalisco, México.
Acuaro de las Lleguas (13); Barolosa (9); Dos Aguas (61); 10 km. NE of Dos Aguas (5).
Heretofore this species has been known only from a few specimens from scattered localities in the Sierra Madre Occidental in southwestern Jalisco and Sinaloa. The collection of a large series of these lizards in virgin pine forest at elevations of more than 2000 meters in the Sierra de Coalcomán now makes possible an analysis of variation in the species.
Superficially S. bulleri resembles S. torquatus, but S. bulleri is smaller, has more dorsal scales, fewer scales in the dark collar, and fewer femoral pores. In 88 specimens of S. bulleri there are 36-41 (38.7) dorsal scales and 2 or 3 (2.6) middorsal scales in the collar, as compared with 28-31 (29.3) dorsal scales and 3 or 4 (3.4) middorsal scales in the collar of 26 specimens of S. torquatus from Uruapan. In 20 adult males of S. bulleri there are 13-15 (14.3) femoral pores, and 13-16 (14.4) in 11 females; 13 males of S. torquatus have 14-21 (17.3) femoral pores, and 13 females have 15-21 (16.7). Seventeen adult males of S. bulleri have snout-vent lengths of 72-91 (82.0); ten females, 71-87 (75.7). In comparison, 13 adult males of S. torquatus have an average snout-vent length of 88.9 mm., and 13 females, 88.5 mm. In S. bulleri there is little variation in the head scales. The frontal is in contact with the interparietal in 63, and not in 24, specimens; the median frontonasal is in contact with the frontal in 13, and not in 74, specimens. In 39 specimens there are two canthals, and in 48 there is one; in 29 specimens there are three preauriculars, and in 58 there are four.
In life adult males have a pale blue tail, bright blue belly patches, a purplish blue throat, and pale blue lines on the sides of the head and neck.
This species was obtained at four localities in the high mountains of the Sierra de Coalcomán. In this mountain range Sceloporus bulleri apparently replaces S. torquatus, a species that is widespread in the Cordillera Volcánica and on the Mexican Plateau. At Dos Aguas and at Acuaro de las Lleguas the lizards were abundant in the tall pine forest, where they were found on standing pine trees, on pine logs, and on rock outcroppings.
Sceloporus dugesi intermedius Dugès
Sceloporus intermedius Dugès, La Naturaleza, 4:29, 1877.—La Noria, near Zamora, Michoacán, México.
Sceloporus dugesii intermedius, Smith, Univ. Kansas Sci. Bull., 24:663, February 16, 1938.
Cojumatlán (6); Jiquilpan (11); Lago de Camécuaro; Lago de Chapala; Morelia (23); Pátzcuaro (84); Quiroga (35); Sahuayo (4); Tacícuaro (2); Tangamandapio (17); Tangancícuaro (9); Zacapu (4); Zamora (11); Zinapécuaro (9).
This lizard is strictly an inhabitant of the Mexican Plateau, where it is found in rocky places, sometimes in pine-oak forest, but more frequently in mesquite-grassland. It is a terrestrial species, and is most often seen on rock fences at elevations of 1500 to 2200 meters.
This species differs from S. bulleri and S. torquatus in having two rows of supraoculars, instead of one; also it has more dorsal scales. Twenty-six specimens of Sceloporus dugesi intermedius from Tangamandapio and Tangancícuaro have 44-48 (45.7) dorsal scales, as compared with an average of 38.7 in S. bulleri and 29.3 in S. torquatus. In life Sceloporus dugesi intermedius has a dull greenish gray dorsum; in males the belly patches are bright blue bordered medially by black, and the throat is bluish gray. The largest specimen examined is a male having a snout-vent length of 80 mm.
Sceloporus gadowae Boulenger
Sceloporus gadoviae Boulenger, Proc. Zool. Soc. London, 1905, 2:246, October 7, 1905.—Mezquititlán, Guerrero, México.
Chupio; El Sabino (77); La Playa (6); Río Marquez, 10 km. S of Lombardia (11).
Although this species has a rather extensive range in the Balsas-Tepalcatepec Basin in the state of Michoacán, Guerrero, Morelos, and Puebla, it is only locally abundant in that area. Usually these lizards are found on rocky cliffs in which there are many crevices for cover. Sceloporus gadowae is abundant on a conglomerate cliff along the Río Marquez south of Lombardia. Although the closely related S. pyrocephalus is abundant in the stream valley and in the hills above the cliff, S. gadowae has been found only on the cliff; few individuals of S. pyrocephalus have been observed on the cliff. A similar situation was discovered on a much more extensive conglomerate cliff along the Río Balsas near Mexcala, Guerrero. Near Tehuitzingo, Puebla, where S. pyrocephalus was not found, S. gadowae was found on conglomerate cliffs. Probably there is strong competition between the two species; possibly this has resulted in the restriction of S. gadowae to isolated cliff-habitats within the extensive range of the more widespread S. pyrocephalus.
In Michoacán Sceloporus gadowae has been found along the lower slopes of the Cordillera Volcánica at elevations from 250 to 1050 meters. All of the localities from which this lizard is known lie in the arid tropical scrub forest.
Sceloporus grammicus microlepidotus Wiegmann
Sceloporus microlepidotus Wiegmann, Herpetologia Mexicana, p. 51, 1834.—México. Type locality restricted to México, Distrito Federal, by Smith and Taylor (1950b:120).
Sceloporus grammicus microlepidotus, Smith and Laufe, Trans. Kansas Acad. Sci., 48:332, December, 1945.
Angahuari; Apo (10); Atzimba (3); Carapan (5); Cerro San Andrés (17); Cerro Tancítaro (18); Corupu; Cuseño Station (2); Jacona; Jeráhuaro (10); Macho de Agua; Mil Cumbres; 46 km. E of Morelia; 60 km. E of Morelia (2); Opopeo (14); Pátzcuaro (30); Puerto Hondo (19); San Gregorio (41); San José de la Cumbre (8); Sierra Patamba; Tancítaro (233); Tupátaro; Undameo; Uruapan (180); between Zacapu and Zamora; 24 km. SE of Zitácuaro; between Zurumbeneo and Cerro Garnica.
This small species of Sceloporus is an ubiquitous inhabitant of the coniferous forests from 1550 to 3100 meters in the Cordillera Volcánica. Usually it is seen on tree trunks, but occasionally on the ground. Near the lower limit of the altitudinal distribution of the species, as at Uruapan, individuals sometimes are found on broad-leafed trees. Apparently Sceloporus heterolepis replaces S. grammicus microlepidotus in the Sierra de Coalcomán.
Sceloporus heterolepis Boulenger
Sceloporus heterolepis Boulenger, Proc. Zool. Soc. London, 1894:731, April, 1895.—La Cumbre de los Arrastrados, Jalisco, México.
Araparicuaro; Cerro Barolosa (6); Dos Aguas (13); Los Conejos; 11 km. N of Uruapan (3).
Although Michoacán has not previously been included in the range of this lizard, it was first collected in the state by Gadow in 1908 (BMNH 1914.1.28.69 from Araparicuaro). The description of S. heterolepis given by Smith (1939:197) can be supplemented by data on the 23 specimens now in the collections of the Museum of Zoology at the University of Michigan. All have two canthals; there are 55 to 71 (63.6) scales in the middorsal row; 1 to 3 rows middorsally are somewhat enlarged and bordered on either side by a row of larger scales bearing high keels. There are 14 to 20 (16.2) femoral pores. Eight adult males have snout-vent lengths from 49 to 61 (58.0) mm. and tail lengths from 57 to 74 (66.0) mm.; four adult females have snout-vent lengths from 52 to 57 (55.2) mm. and tail lengths from 60 to 66 (63.5) mm. The smallest of eight juveniles has a snout-vent length of 28 mm. and a tail length of 32 mm. The dorsum in adults is pale grayish brown; there are three irregular chevron-shaped dark marks and a triangular dark brown mark above the insertion of the hind limbs; on the tail are dark brown rings. There are scattered faint blue flecks on the flanks and narrow transverse dark lines on the lower limbs. Males have pale bluish green belly patches and an orange-salmon-colored throat; the belly in females is pale orange-tan. The juveniles have a more contrasting color pattern; the dark chevrons on the dorsum are bordered posteriorly by pale gray.
In Michoacán this species has been obtained in pine and pine-fir forests from 1800 to 2700 meters. On Cerro Barolosa and at Dos Aguas, both in the Sierra de Coalcomán, the lizards were found beneath the bark of dead, standing pines. In the Sierra de Coalcomán Sceloporus heterolepis seems to fill the niche of the small arboreal Sceloporus in the coniferous forest in southwestern México, a position held by S. grammicus microlepidotus in the Cordillera Volcánica; the latter species does not occur in the Sierra de Coalcomán. Five specimens of Sceloporus heterolepis are known from the Cordillera Volcánica, whereas 603 of S. grammicus microlepidotus have been collected there. The ecological relationships that exist between the two species in the Cordillera Volcánica are not known.
Insofar as is known, Sceloporus heterolepis reaches the southern limits of its range in the Sierra de Coalcomán and in the western part of the Cordillera Volcánica. Other records for the species are from the Sierra Madre Occidental in Jalisco. Langebartel (1959) described Sceloporus shannonorum from the mountains near the Durango-Sinaloa border; the single specimen of S. shannonorum differs significantly from S. heterolepis only in having fewer dorsal scales (48). The acquisition of additional material, especially from Nayarit and northern Jalisco, probably will provide a basis for showing that these two populations are conspecific.
Sceloporus horridus oligoporus Cope
Sceloporus oligoporus Cope, Proc. Acad. Nat. Sci. Philadelphia, 16:177, September 30, 1864.—Colima, Colima, México.
Sceloporus horridus oligoporus, Taylor, Univ. Kansas Sci. Bull., 24:520, February 16, 1938.
Aguililla; Apatzingán (50); Arteaga (2); Capirio (2); Cascada Tzararacua; Charapendo (4); Coahuayana (3); Coalcomán (32); 19 km. S of Corralito; 27 km. E of Dos Aguas; El Sabino (55); El Ticuiz; Huetamo (2); Jazmin; Jungapeo (2); La Orilla (2); La Placita; Limoncito (3); Playa Azul (5); Tzitzio (8); Uruapan (4); Volcán Jorullo (2); Ziracuaretiro; Zirimícuaro (13).
All of the specimens from Michoacán seem to be typical S. horridus oligoporus; none has more than six femoral pores.
Characteristically this species is found in open arid scrub forest; it reaches its greatest abundance in rocky areas in which there are scattered leguminous trees and bushes. It has been found in these low trees and bushes almost as frequently as it has been found on the ground; none has been seen in large trees or far above the ground. Altitudinally, this species ranges from sea level to about 1600 meters.
Sceloporus melanorhinus calligaster Smith
Sceloporus melanorhinus calligaster Smith, Proc. U. S. Natl. Mus., 92:360, November 5, 1942.—Acapulco, Guerrero, México.
Aguililla; Apatzingán (18); Barranca de Herradero; Capirio (19); Coahuayana (4); Coalcomán (2); Cofradía (4); El Cerrito; El Sabino (33); El Ticuiz (3); La Placita (6); Lombardia (4); Playa Azul; Río Marquez, 10 km. S of Lombardia (2); Río Marquez, 13 km. SE of Nueva Italia (4); Salitre de Estopila; San Juan de Lima (2); Santa Ana; Tzitzio; Ziracuaretiro.
Smith (1942a:360) diagnosed Sceloporus melanorhinus calligaster as having fewer femoral pores than the other subspecies of S. melanorhinus and as having the lateral belly patches in the males confluent in the midline. Examination of forty specimens from the Tepalcatepec Valley and the coastal regions of Michoacán does not substantiate this diagnosis. The number of femoral pores varies from 15 to 22 (18.9); 14 individuals (35%) had 20 or more femoral pores. Smith (loc. cit.) stated that S. melanorhinus in Oaxaca had 18 to 27 (21.6) femoral pores and that 77 per cent of the specimens had more than 20 femoral pores. Of the 24 males examined from Michoacán, 18 have the lateral belly patches separated in the midline. Usually they are separated by no more than one scale, but in some individuals they are separated by two or more scales. Although the above data minimize certain differences between the northern and southern populations of this species, certain of the color pattern characters seem to be diagnostic of the subspecies inhabiting the Pacific lowlands from Guerrero to Nayarit. Large adults of S. m. calligaster have only a faint dorsal pattern, which in the subspecies melanorhinus and stuarti consists of a series of large, dark, interconnected triangles on the back. This pattern is present in young and small adults of S. m. calligaster; furthermore, in this subspecies the ventral coloration of the males differs from that found in the more southern populations. Adult males of S. m. calligaster have a black throat, that changes to brilliant blue posteriorly, and a large white spot medially on the chin. This spot is present in some specimens from Oaxaca and Chiapas, but, if present, it is much smaller and less distinct than in specimens from Michoacán. In S. m. calligaster the chest and midventral area are orange to salmon-color.
A male from Lombardia in life was colored as follows: Dorsum grayish tan bearing faint bluish gray flecks; chest deep salmon-orange, this color continuing down midventral area to the somewhat paler groin; belly patches pale blue fading to pale green laterally; throat black anteriorly enclosing a white spot; throat blue posteriorly and bluish green posterolaterally.
Individual lizards were observed to change in dorsal color from a pale ashy gray to a rather dull brown. Normally, inactive individuals and those observed on overcast days were dull brown.
Sceloporus melanorhinus calligaster is found in trees in riparian situations in the lowlands to elevations of about 1500 meters. It does not inhabit the arid tropical scrub forest in the Tepalcatepec Valley or on the coast, but in those areas is found in the gallery forests along streams and rivers. The lizards are wary and live high in the trees; they are especially difficult to locate in the rainy season, when the trees are in full leaf.
Sceloporus pyrocephalus Cope
Sceloporus pyrocephalus Cope, Proc. Acad. Nat. Sci. Philadelphia, 16:177, September 30, 1864.—Colima, Colima, México.
Acahuato (2); Apatzingán (142); Arteaga (4); 26 km. S of Arteaga (4); Capirio (6); Chinapa; Chupio; 19 km. S of Corralito (5); El Sabino (220); Jazmin (3); La Placita (8); La Playa (14); La Salada (6); Lombardia (5); Nueva Italia (14); Ojos de Agua de San Telmo (2); Oropeo (3); Ostula; Punta de San Telmo (3); Río Cancita, 14 km. E of Apatzingán (13); Río Marquez, 10 km. S of Lombardia (10); Río Marquez, 13 km. SE of Nueva Italia (3); San Juan de Lima (2); Santa Ana (2); Tafetan (2); Tepalcatepec (2); Tzitzio (6); Volcán Jorullo (3).
This small species is extremely common in the Tepalcatepec Valley and noticeably less so on the coast. It is usually found on the ground in rocky areas, but males frequently have been seen on the trunks of low trees in the scrub forest. Altitudinally, it ranges from sea level to slightly more than 1000 meters. The sexes are readily distinguished in the field (Oliver, 1937; Smith, 1939; Duellman, 1954b). In the dry season only males were observed in the Tepalcatepec Valley, but in the rainy season both sexes were found in approximately the same numbers.
Sceloporus scalaris scalaris Wiegmann
Sceloporus scalaris Wiegmann, Isis von Oken, 21:370, 1828.—México. Type locality restricted to México, Distrito Federal, by Smith and Taylor (1950b:137).
Sceloporus scalaris scalaris, Smith, Occ. Pap. Mus. Zool. Univ. Michigan, 361:2, December 15, 1937.
Carapan (2); Cherán; Ciudad Hidalgo; Huingo (3); Jacona (3); Jiquilpan (2); Lago de Camécuaro (2); Lago de Chapala; Lago de Cuitzeo (5); Morelia (4); Pátzcuaro (4); Queréndaro; Quiroga; Tacícuaro (5); Tarécuaro; Zacapu (4); Zamora (4); Zinapécuaro (11).
This small terrestrial species does not seem to be abundant anywhere in the state. It sometimes is found in open pine, oak, or pine-oak forest, but usually it is observed in areas supporting bunch grass. In such places the lizards sun and forage on the open ground and quickly take refuge in the large clumps of grass. Altitudinally, the species ranges from 1550 to 2300 meters. Although Sceloporus scalaris scalaris has been found in association with S. dugesi intermedius, S. spinosus, and S. torquatus, it does not seem to form any close ecological association with any of these species. In the pine forests of the Cordillera Volcánica S. s. scalaris is replaced by Sceloporus aeneus aeneus, another small terrestrial species that occurs in great abundance throughout the coniferous forests of the Cordillera Volcánica.
Sceloporus siniferus siniferus Cope
Sceloporus siniferus Cope, Proc. Amer. Philos. Soc., 11:159, 1869.—Pacific side of the Isthmus of Tehuantepec. Type locality restricted to Tehuantepec, Oaxaca, México, by Smith and Taylor (1950b:134).
Sceloporus siniferus siniferus, Smith and Taylor, Bull. U. S. Natl. Mus., 199:134, October 26, 1950.
Twenty-six km. S of Arteaga; Barranca de Bejuco (2); Coahuayana; El Ticuiz (2); La Mira; La Orilla (2); La Placita (9); Maruata; Ojos de Agua de San Telmo; Ostula (4); Playa Azul (6); Pómaro (2); Puerto de las Higuerita; Santa Ana (3).
This small terrestrial species inhabits the dense arid tropical scrub forest on the coast and lower foothills of the Sierra de Coalcomán to elevations of about 150 meters. It also occurs in the lower Balsas Valley, but it has not been found in the scrub forest of the broad Tepalcatepec Valley. Perhaps the large number of Sceloporus siniferus on the coastal lowlands is responsible for the small number there of S. pyrocephalus, another terrestrial species of about the same size. The latter is abundant in the Tepalcatepec Valley, where S. siniferus siniferus has not been found. Sceloporus siniferus siniferus is a fast runner and difficult to collect; consequently, the small number of specimens available is not indicative of its abundance.
Sceloporus spinosus spinosus Wiegmann
Sceloporus spinosus Wiegmann, Isis von Oken, 21:370, 1828.—México. Type locality restricted to Puebla, Puebla, México, by Smith and Taylor (1950b:116).
Sceloporus spinosus spinosus, Martín del Campo, Anal. Inst. Biol. México, 8:262, 1937.
Cojumatlán (2); Huetamo Road; Lago de Cuitzeo (4); Maravatio (8); Tupátaro (2).
Although this species is widespread on the southern part of the Mexican Plateau, it is uncommon in Michoacán. It has been collected only in rather open situations in the mesquite-grassland on the plateau between 1500 and 2300 meters, where it has been found in association with Sceloporus dugesi intermedius and S. scalaris scalaris. Most specimens of Sceloporus spinosus spinosus have been observed on rock fences. In this habitat the species is the larger member of a pair of species, the smaller of which is Sceloporus dugesi intermedius.
Sceloporus torquatus torquatus Wiegmann
Sceloporus torquatus Wiegmann, Isis von Oken, 21:369, 1828.—México. Type locality restricted to México, Distrito Federal, by Smith and Taylor (1950b:126).
Sceloporus torquatus torquatus, Cope, Proc. Amer. Philos. Soc., 22:402, 1885.
Angahuan (31); Araparicuaro; Capácuaro (3); Carapan (11); Cerro Tancítaro; Cherán; Ciudad Hidalgo; Cojumatlán; Copándaro (2); Corupu (4); Cuseño Station (9); El Álamo; Jacona (6); Jiquilpan (2); Jungapeo (3); Lago de Camécuaro; Lago de Chapala; Lago de Cuitzeo (3); La Palma (2); Los Conejos (3); Los Reyes (3); Maravatio (9); Morelia (17); Paracho (3); Pátzcuaro (27); Pino Gordo; Queréndaro (2); Quiroga; Sahuayo (3); San José de la Cumbre; San Juan de Panangaricutiro; Tacícuaro (10); Tancítaro (200); Tangamandapio; Tangancícuaro (3); Temazcal (2); Tupátaro (5); Uruapan (136); Zacapu; Zinapécuaro (10); Zirimícuaro (12); Zitácuaro.
This large species inhabits the Mexican Plateau and the Cordillera Volcánica, but not the Sierra de Coalcomán, where apparently it is replaced by Sceloporus bulleri. Sceloporus torquatus torquatus usually is found in pine or pine-fir forests at elevations between 1450 and 3000 meters. In many places it is almost entirely arboreal, but in areas where there are many fallen trees or rock fences and rock piles, many individuals have been found on the ground near the rocks or logs. In the coniferous forests this species is associated with S. grammicus microtepidotus and S. aeneus aeneus.
The distinction made by Smith (1938:572) between the subspecies S. torquatus torquatus and melanogaster is slight. Individuals with pale bluish spots are found throughout the range of the species in Michoacán; spotting is especially evident in the young. Individuals having an incomplete nuchal collar have been found at Maravatio and at Zinapécuaro in the northern part of the state; in this character these specimens resemble S. torquatus melanogaster, which is found to the north from Guanajuato to Zacatecas and San Luis Potosí.
Sceloporus utiformis Cope
Sceloporus utiformis Cope, Proc. Acad. Nat. Sci. Philadelphia, 16:177, September 30, 1864.—Colima, Colima, México.
Nineteen km. S of Arteaga (2); Cascada Tzararacua (17); Coahuayana (3); Coalcomán (6); El Sabino (2); El Ticuiz (2); Ostula (3); Pómaro; Río Cachán; San Juan de Lima; Uruapan (26).
In Michoacán the range of this species is discontinuous. It has been found between 1050 and 1550 meters on the slopes of the Cordillera Volcánica, and on the coast and seaward slopes of the Sierra de Coalcomán up to an elevation of 900 meters. It is absent from the Tepalcatepec Valley. At Uruapan and at Cascada Tzararacua this lizard was found on the ground in oak forest or in open pine-oak forest; on the coast and foothills of the Sierra de Coalcomán it was found on the ground in the gallery forests along streams, and not in the scrub forest.
Urosaurus bicarinatus tuberculatus (Schmidt)
Uta tuberculata Schmidt, Amer. Mus. Novitates, 22:4, December 1, 1921.—Colima, Colima, México.
Urosaurus bicarinatus tuberculatus, Mittleman, Bull. Mus. Comp. Zool., 91:169, September, 1942.
Twenty-six km. S of Arteaga; Cascada Tzararacua (2); Chupio; Coahuayana; Coalcomán (8); El Sabino (2); Jungapeo; La Orilla (2); La Placita (4); Playa Azul (4); Pómaro (2); San Salvador (16);? Tupátaro; Uruapan (12); Tzitzio; Zamora.
The known distribution and geographic variation of Urosaurus bicarinatus in southwestern México presents a confused picture. In general rugosity, specimens from the coastal region of Michoacán (Coahuayana, La Orilla, La Placita, Playa Azul, and Pómaro) resemble U. bicarinatus tuberculatus to the north along the Pacific coast. Furthermore, specimens from the coast have less stippling in the gular region than do those from the Sierra de Coalcomán and the slopes of the Cordillera Volcánica. Specimens from the mountains have greatly carinate enlarged dorsals, large lateral tubercles, and heavily stippled throats; in these characters they resemble specimens from Morelos, Guerrero, and Oaxaca. As mentioned by Peters (1954:14), some specimens from La Orilla and San Salvador are like U. bicarinatus bicarinatus in certain characters, and one specimen has the blue ventral patches restricted to the sternal area, a characteristic of U. bicarinatus anonymorphus of Oaxaca and eastern Guerrero. Examination of all available specimens from Michoacán indicates that the nature of the dorsal scales is of little value in separating the subspecies. The specimens from Michoacán are here provisionally referred to U. bicarinatus tuberculatus, because cursory examination of specimens from several localities between Nayarit and Oaxaca shows that there are only minor differences between the named populations. Individuals from the northern part of the range are more rugose and have larger blue ventral patches and less gular stippling than those from the south.
In Michoacán Urosaurus bicarinatus tuberculatus is found in wooded areas, not in open scrub forest, in the coastal area to elevations of about 900 meters, and along the slopes of the Cordillera Volcánica and the southern edge of the Mexican Plateau at elevations from 1000 to 1700 meters. The record for Tupátaro probably is erroneous, for no other specimens of this species are known from the central plateau. Essentially, the distribution of this species parallels that of Sceloporus utiformis, a strictly terrestrial species. Urosaurus bicarinatus tuberculatus lives on tree trunks. Below 1000 meters in the Tepalcatepec Valley Urosaurus bicarinatus tuberculatus is replaced by Urosaurus gadowi.
Urosaurus gadowi (Schmidt)
Uta gadovi Schmidt, Amer. Mus. Novitates, 22:3, December 1, 1921.—Cofradía, Jalisco, México (in error) = Cofradía, Michoacán, México (Duellman, 1958b:49).
Urosaurus gadowi, Mittleman, Bull. Mus. Comp. Zool., 91:154, September, 1942.
Acahuato (2); Apatzingán (56); 12-16 km. S of Apatzingán (12); Buenavista (7); Capirio (23); Cofradía (21); El Sabino (13); Guayabo; Jazmin; La Playa; La Salada (3); Nueva Italia (7); Rancho Nuevo; Río Cancita, 14 km. E of Apatzingán (5); Río Marquez, 10 km. S of Lombardia (2); Río Marquez, 13 km. SE of Nueva Italia (3); San Salvador (2); Santa Ana; Tepalcatepec; Volcán Jorullo (3); Zicuiran (2); Ziracuaretiro.
Although individuals of this species have been collected at elevations slightly exceeding 1200 meters on Volcán Jorullo and at 1100 meters at Ziracuaretiro on the southern slopes of the Cordillera Volcánica, for the most part these lizards are found at elevations of less than 800 meters, where they inhabit the open arid scrub forest of the Tepalcatepec Valley, a region to which this species is endemic (Duellman, 1958b:49). These small lizards usually are found on the trunks and main branches of the small trees in the scrub forest; in this habitat they are associated with Sceloporus horridus oligoporus, a much larger species.
Males have a pale orange spot on the throat and a pale blue belly; females have immaculate venters.
A specimen from Guayabo on the northern slopes of the Sierra de Coalcomán was referred to Urosaurus irregularis (Fischer) by Peters (1954:15). I have studied this specimen (BMNH 1914.1.28.110), a female having a snout-vent length of 46 mm., and agree with Peters that it closely resembles Fischer's description and figure (1882: pl. 17, fig. 1). This specimen and those seen of Urosaurus gadowi all have pavementlike enlarged dorsal scales that are complete across the vertical line. In U. gadowi the enlarged dorsals usually are in four to six irregular rows; in the specimen from Guayabo the dorsals are in two rows. Although none of the other specimens of U. gadowi examined has only two rows of enlarged dorsals, I prefer to consider the specimen from Guayabo as an aberrant individual of that species, rather than U. irregularis. Guayabo is in the known range of U. gadowi. Urosaurus irregularis is known only from the type specimen in the Bremen Museum; the type locality, according to Fischer (1882:232), is "Aus dem Hochlande von Mexico." If an examination of the type specimen of U. irregularis shows it to be identical with U. gadowi, then U. irregularis would be the name for the lizards here referred to U. gadowi.
Mabuya brachypoda Taylor
Mabuya brachypoda Taylor, Univ. Kansas Sci. Bull., 38 (1):308, December 20, 1956.—Four kilometers east-southeast of Los Angeles de Tilarán, Guanacaste, Costa Rica.
El Sabino (42); La Placita; Playa Azul; Tzitzio (3).
Previously this species has been reported from La Placita as Mabuya mabouya alliacea by Peters (1954:15). Webb (1958:1311) provided evidence that Mexican specimens were conspecific with Mabuya brachypoda, as described from Costa Rica by Taylor (1956:308). The large series in the Taylor collection studied by Webb and listed by him as being from Uruapan actually is part of a series collected by Hobart M. Smith at El Sabino at an elevation of 1050 meters, 30 kilometers south of Uruapan.
This species probably ranges throughout the coastal region of the state; individuals from La Placita and Playa Azul were taken in dense scrub forest near sea level.
Scincella assata taylori (Oliver)
Leiolopisma assatum taylori Oliver, Occ. Pap. Mus. Zool. Univ. Michigan, 360:12, November 20, 1937.—Santiago, Colima, México.
Scincella assata taylori, Mittleman, Herpetologica, 6:20, June 5, 1950.
Twenty-one km. S of Arteaga; Ostula.
The specimen from Ostula was obtained in semi-deciduous broad-leaf forest at an elevation of 120 meters; that from 21 kilometers south of Arteaga was taken in oak forest at an elevation of 830 meters. Both localities are on the coastal slopes of the Sierra de Coalcomán. Probably the species inhabits the heavy forests on the lower slopes of these mountains. The specimen from south of Arteaga (UMMZ 119117) in life had a tan dorsum and a bright orange-pink tail.
Eumeces altamirani Dugès
Eumeces altamirani Dugès, La Naturaleza, ser. 2, 1:485, 1891.—Apatzingán, Michoacán, México.
Twelve km. E of Apatzingán; El Sabino (4).
One specimen of this rare species was found beneath a rock in the open scrub forest 12 kilometers east of Apatzingán on July 3, 1955. Another skink, presumably of this species, was seen at Capirio. The specimen from east of Apatzingán is a male having a snout-vent length of 97 mm. and an incomplete tail. In most respects it compares favorably with accounts of the species given by Taylor (1936b:55 and 1936c:102). The frontal is divided by a transverse suture; the enlarged dorsal scales are arranged in 11 pairs anteriorly, followed by 48 unpaired enlarged scales. The head and middorsal area are brown; there is a pale tan stripe on the edges of the vertebral and paravertebral rows, bordered by a dark brown stripe on the paravertebral row, which, in turn, is bordered by a pale tan stripe on the lateral edge of the paravertebral scale row and the median edge of the adjacent scale row. The stripes extend from the neck to the base of the tail. The flanks are mottled with brown and cream-color; the labials are cream-color barred by brown; the venter is a pale cream-color.
Dugès (1891:485) described Eumeces altamirani from "las regiones cálidas del Estado de Michoacán" and subsequently (1896:480) gave Apatzingán as a locality for the species. Presumably he had only one specimen. In 1935 Hobart M. Smith collected the species at El Sabino on the lower slopes of the Cordillera Volcánica bordering the Tepalcatepec Valley. All of the known specimens are from this valley and the adjacent slopes, an area to which the species apparently is endemic.
Eumeces colimensis Taylor
Eumeces colimensis Taylor, Publ. Field Mus. Nat. Hist., zool. ser., 20:77, May 15, 1935.—Colima, Colima, México.
Coalcomán; Salitre de Estopila.
The species was reported by Peters (1954:16); no additional material has been discovered. The species is known only from foothills and low mountains at elevations between 130 and 950 meters in Michoacán and Colima.
Eumeces copei Taylor
Eumeces copei Taylor, Proc. Biol. Soc. Washington, 46:133, June 5, 1933.—10 miles southeast of Asunción, México, México. Cerro Tancítaro (3); Zacapu.
This member of the Eumeces brevirostris-group has been found only in pine or pine-fir forests at elevations from 1800 to 2700 meters. It probably ranges throughout the high mountains of the state north of the Tepalcatepec Valley; its apparent absence in other parts of the Cordillera Volcánica, other than on Cerro Tancítaro, is surprising. The species has been taken near Asunción in the state of México and at Lagunas de Zempoala in Morelos.
In this species the lateral pale yellow stripe, which is bordered below by dark brown, extends to the groin and onto the base of the tail. The dorsolateral stripe is separated from the copper-colored middorsum by a narrow brown stripe.
Eumeces dugesi Thominot
Eumeces Dugesii Thominot, Bull. Soc. Philom. Paris, ser. 7, 7:138, 1883.—Guanajuato. Type locality restricted to Guanajuato, Guanajuato, México, by Smith and Taylor (1950b:169).
Carapan (6); Cherán (5); Opopeo (2); 17 km. S of Pátzcuaro (3); San José de la Cumbre (2); Tancítaro (2); Tangancícuaro; Uruapan; Zacapu.
Individuals of this species frequently have been found beneath rocks and logs in pine-oak, pine, or fir forests from elevations of 1550 to 1850 meters. To judge from specimens available, E. dugesi probably is the most abundant and widespread species of skink in the state.
In this species the lateral yellow stripe is indistinct and is persistent only in the axilla; the dorsolateral stripes terminate anterior to the hind limbs and are not separated from the tan dorsum.
Eumeces indubitus Taylor
Eumeces indubitus Taylor, Univ. Kansas Sci. Bull., 21:257, November 27, 1934.—Near Cuernavaca, Morelos, México.
Puerto Hondo.
The one specimen of this species from Michoacán was collected by Edward H. Taylor in pine forest at Puerto Hondo, near Zitácuaro, at an elevation of about 2750 meters (Taylor, 1935:466). The species is known from the high mountains of eastern Michoacán, western México, and northern Morelos.
Eumeces parvulus Taylor
Eumeces parvulus Taylor, Proc. Biol. Soc. Washington, 46:175, October 26, 1933.—Tepic, Nayarit, México.
El Ticuiz; La Placita; Pómaro (2); San Pedro Naranjestila (3).
Aside from the specimens reported by Peters (1954:17), one other specimen was obtained at El Ticuiz. It has 22 scale rows, 3 supraoculars in contact with the frontal, 2 postlabials, and a unicolored olive-tan dorsum. In life the anterior dorsolateral stripes were pale pinkish tan, the labials cream color, the throat white, and the tail pale blue. All specimens were found in semi-deciduous broad-leaf forest at elevations of less than 500 meters on the seaward slopes of the Sierra de Coalcomán.
Ameiva undulata sinistra Smith and Laufe
Ameiva undulata sinistra Smith and Laufe, Univ. Kansas Sci. Bull., 31 (1):59, May 1, 1946.—Manzanillo, Colima, México.
Apatzingán (9); 19 km. S of Arteaga (3); Barranca de Bejuco (2); Coahuayana (6); Coalcomán (3); El Ticuiz (10); La Placita (2); Limoncito (3); Ostula (2); Playa Azul; Salitre de Estopila; San Juan de Lima (2); San Pedro Naranjestila (4).
Six males and six females from the Tepalcatepec Valley have more femoral pores than do 16 males and nine females from the coastal lowlands; the ranges and average number of femoral pores in the former are 40-50 (44.8) for males and 38-40 (38.6) for females; males from the coast have 34-44 (39.2), and females have 32-40 (36.2) femoral pores. In all specimens the number of lamellae beneath the fourth toe varies from 26 to 33 (29.7). In life juveniles have a pale olive-tan dorsum and a dorsolateral dark band, superimposed on which is a row of darker brown spots. The dorsolateral band is bordered below by a narrow cream-colored stripe. The tail is tan above and grayish white below; the belly is pale bluish white. Adult males are brilliantly colored in life. A male having a snout-vent length of 108 mm. had a rusty brown dorsum and bright blue bars on the flanks separated by dark brown interspaces. The side of the head was pale green, and the chin and throat were golden yellow. In some specimens the throat is orange. Juveniles and subadults have dark flecks on the brown or tan middorsal area, but these are absent in the largest males.
This species inhabits the heavily wooded areas in the lowlands to elevations of about 950 meters. In the Tepalcatepec Valley it has been found only in gallery forests along streams. In both the Tepalcatepec Valley and the coastal lowlands there is a noticeable absence of large adults in the dry season.
Cnemidophorus calidipes Duellman
Cnemidophorus calidipes Duellman, Occ. Pap. Mus. Zool. Univ. Michigan, 574:1, December 23, 1955.—Capirio, Michoacán, México.
Apatzingán (56); 12-20 km. S of Apatzingán (5); 19 km. E of Apatzingán (5); 25 km. S of Arteaga; Capirio (57); El Espinal (13); Jazmin (9); 11 km. S of Lombardia; Nueva Italia.
This small, distinctive species of the sexlineatus-group of Cnemidophorus was discovered in the Tepalcatepec Valley in 1955 (Duellman, 1955); subsequent field studies showed it to be widespread in the valley (Duellman, 1960c). One specimen (KU 29747) is from the relatively arid, low Pacific slope of the Sierra de Coalcomán, 25 kilometers south of Arteaga. All other specimens have been taken at elevations of 200 to 650 meters in the Tepalcatepec Valley, where the species characteristically inhabits the open scrub forests of the valley floor, especially the Cercidium-Prosopis-Apoplanesia associations, where there is a sparse growth of grasses. In this habitat it is most frequently seen in association with Cnemidophorus costatus zweifeli and C. deppei infernalis.
Aside from the characters given in Table 5, Cnemidophorus calidipes differs from other species of Cnemidophorus in Michoacán by possessing a complete (or nearly so) supraorbital semicircle-series of granules; in other species the granules seldom extend anteriorly beyond the posterior border of the frontal.
Cnemidophorus communis communis Cope
Cnemidophorus communis Cope, Proc. Amer. Philos. Soc., 17:95, 1877.—No type locality given; type locality restricted to Colima, Colima, México, by Zweifel (1959a:74).
Cnemidophorus communis communis, Zweifel, Bull. Amer. Mus. Nat. Hist., 117:74, April 27, 1959.
Aguililla (2); Apatzingán (6); 13 km. S of Arteaga (2); 19 km. S of Arteaga (3); Capirio (3); Coahuayana (3); Coalcomán (44); El Ticuiz; between El Ticuiz and Ojos de Agua de San Telmo; La Placita (6); Pómaro (2); Río Cachán; Salitre de Estopila; San Juan de Lima.
The specimens from Coalcomán and the coastal localities were referred to Cnemidophorus sacki copei by Peters (1954:18) and Duellman (1954b:12). Zweifel (1959a) referred these specimens to Cnemidophorus communis communis and pointed out the probable sympatry of C. communis and C. costatus (= sacki of Zweifel) in the Tepalcatepec Valley.
There is considerable geographic variation in the number of dorsal granules around the midbody. Sixteen specimens from the coastal regions of Michoacán have 129-146 (136.3) granules; nine from the Tepalcatepec Valley have 124-137 (128.3), and 44 from Coalcomán at an elevation of 950 meters in the Sierra de Coalcomán, intermediate geographically between the coast and the Tepalcatepec Valley, have 105-144 (119.7). The number of granules in specimens from the coast of Michoacán compares favorably with the range of 118-154 (137.8) for 34 specimens from Colima, Colima (Zweifel, 1959a:107). Aside from the characters given in Table 5, C. communis communis can be distinguished from other members of the Cnemidophorus sexlineatus-group (calidipes, costatus, and scarlaris) by its relatively small post-antebrachial scales.
Table 5.—Comparison of the Ten Species and Subspecies of Cnemidophorus in Michoacán (Scale Counts Are for Specimens from Michoacán Only)
| Species | Dorsal granules | Femoral pores | Adult color pattern | Throat color | Maximum snout-vent length |
| calidipes | 66-86 (75) | 31-47 (39) | Light brown dorsum with vertical blue bars and spots | Pink | 79 mm. |
| communis communis | 105-146 (124) | 38-52 | Green dorsum with six rows of yellow spots | Pink | 135 mm. |
| costatus occidentalis | 97-102 (99) | 37-43 (39) | Cross-bars anteriorly and pale spots posteriorly | Pink | 126 mm. |
| costatus zweifeli | 91-117 (106) | 32-49 (41) | Lateral and dorsolateral rows of spots; paravertebrals fused with pale green middorsum | Pink with blue spot | 132 mm. |
| deppei deppei | 116-117 (116) | 37-38 (37) | Green paravertebral and dorsolateral stripes; lateral stripe broken into row of bluish spots | Black | 93 mm. |
| deppei infernalis | 91-120 (101) | 31-43 (36) | Green paravertebral and dorsolateral stripes; broad cream lateral stripe; reddish flanks | Black | 84 mm. |
| lineatissimus exoristus | 108-140 (122) | 32-47 (39) | Paravertebral stripes fused with yellow middorsal stripe; vertical bars on flanks | Pink and black | 98 mm. |
| lineatissimus lineatissimus | 117-126 (121) | 32-37 (35) | Eight distinct stripes plus partially fused vertebrals | Bluish-pink and black | 96 mm. |
| lineatissimus lividus | 126-164 (148) | 32-48 (38) | Broad middorsal stripe; paravertebrals distinct; blue lateral spots | Pink and black | 106 mm. |
| scalaris | 80-92 (86) | 32-41 (35) | Six distinct cream stripes; tan spots in dark fields | Orange-pink | 95 mm. |
Although this is the largest species of Cnemidophorus in Michoacán (adult males attain a snout-vent length of 135 mm.), it is neither widespread nor abundant. On the coastal lowlands it occurs primarily with Cnemidophorus lineatissimus lividus. In the coastal lowlands there is little open scrub forest, a type of habitat that seems to be preferred by C. communis communis. In the Tepalcatepec Valley, C. communis communis occurs in the open scrub forest with the more abundant large species C. costatus (subspecies zweifeli). Only in the scrub forest in the Coalcomán Valley, where no other species of Cnemidophorus occurs, is C. communis communis abundant.
Cnemidophorus costatus occidentalis Gadow
Cnemidophorus communis occidentalis Gadow, Proc. Zool. Soc. London, 1906, 1:339, August 23, 1906.—Type locality restricted to Ixtlán, Nayarit, México, by Smith and Taylor (1950b:182).
Cnemidophorus costatus occidentalis, Zweifel, Copeia, No. 1:98; March 17, 1961.
Jiquilpan (4).
Only four specimens from the extreme northwestern part of the state are referable to this subspecies. These have 97 to 102 dorsal granules at midbody and lack the blue gular band or spot characteristic of the subspecies in the Tepalcatepec Valley. Probably C. costatus occidentalis ranges throughout the Chapala depression, but to the east it is replaced by Cnemidophorus scalaris scalaris.
Cnemidophorus costatus zweifeli Duellman
Cnemidophorus sacki zweifeli Duellman, Univ. Kansas Publ. Mus. Nat. Hist., 10:589, May 2, 1960.—Capirio, Michoacán, México.
Apatzingán (107); Buenavista (3); Capirio (31); Charapendo (12); Chinapa (2); 19 km. S of Corralito (3); Jazmin (2); between La Playa and Volcán Jorullo (2); Limoncito (3); 14 km. S of Lombardia (11); Nueva Italia (15); Río Marquez, 10 km. S of Lombardia (2); Río Marquez, 13 km. SE of Nueva Italia; Tafetan (18); 14 km. E of Tepalcatepec (2); Tzitzio (11); 19 km. S of Tzitzio; Volcán Jorullo (5); Ziracuaretiro; Zirimícuaro.
These lizards were referred to Cnemidophorus sacki copei by Duellman (1954b:12 and 1955:6); Duellman (1960a) described the subspecies zweifeli and assigned it to Cnemidophorus sacki. Zweifel (1961:98) used the specific name C. costatus for the whiptails on the southwestern part of the Mexican Plateau (C. c. occidentalis). Since occidentalis and zweifeli are conspecific, the combination C. costatus zweifeli is used here for the population inhabiting the Tepalcatepec Valley.
This lizard is abundant in the Tepalcatepec Valley, where it lives in open and dense scrub forest, usually at elevations of less than 1000 meters. Throughout the valley it is found in association with Cnemidophorus deppei infernalis, and in the lower parts of the valley it also is associated with Cnemidophorus calidipes. Observations made in the dry season indicate that large adults are not active at that time.
On the coastal lowlands and in the valleys in the Sierra de Coalcomán Cnemidophorus costatus zweifeli is replaced by C. communis communis. To the east in the Balsas Basin C. costatus zweifeli intergrades with C. costatus costatus.
Cnemidophorus deppei deppei Wiegmann
Cnemidophorus deppei Wiegmann, Herpetologia Mexicana, p. 29, 1834.—México. Type locality restricted to Tehuantepec, Oaxaca, México, by Smith and Taylor (1950b:179).
Cnemidophorus deppei deppei, Cope, Trans. Amer. Philos. Soc., 17:31, 1892.
Salitre de Estopila; San Pedro Naranjestila.
This small species, which is extremely abundant on the coastal lowlands of Guerrero, seems to be rare on the coast of Michoacán, where it has been taken at elevations of 130 and 500 meters in open situations in otherwise forested areas. Duellman and Wellman (1960:25) discussed these specimens in relation to their subspecific assignment. They were referred to Cnemidophorus deppei lineatissimus by Peters (1954:18).
Cnemidophorus deppei infernalis Duellman and Wellman
Cnemidophorus deppei infernalis Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:32, February 10, 1960.—Mexcala, Guerrero, México.
Acahuato; Apatzingán (227); Capirio (3); El Sabino; Jazmin; La Playa (6); Lombardia (6); Nueva Italia (4); Río Marquez, 10 km. S of Lombardia (6); Río Marquez, 13 km. SE of Nueva Italia (10); south of Tancítaro; Volcán Jorullo (3).
This is one of the most abundant and widespread lizards in the Tepalcatepec Valley. Throughout its range it is ecologically associated with Cnemidophorus costatus zweifeli, which ranges to elevations somewhat higher than the 1050 meters known for C. deppei infernalis. This small lizard reaches its greatest abundance in grassy areas on the floor of the Tepalcatepec Valley, where in the Cercidium-Prosopis-Apoplanesia associations it occurs with Cnemidophorus calidipes.
Duellman and Wellman (1960) discussed the variation and relationships of Cnemidophorus deppei, of which the subspecies infernalis is restricted to the Balsas-Tepalcatepec Basin.
Cnemidophorus lineatissimus exoristus Duellman and Wellman
Cnemidophorus lineatissimus exoristus Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:44, February 10, 1960.—Rancho Santa Ana, four kilometers northeast of San Salvador, Michoacán, México.
Thirteen to 25 km. S of Arteaga (18); Capirio (19); Limoncito (13); Santa Ana (22).
As in Cnemidophorus calidipes, the distribution of this subspecies seems to be restricted to the Tepalcatepec Valley, except in the vicinity of Arteaga, where it occurs on the southern slope of the Sierra de Coalcomán. As pointed out by Duellman and Wellman (1960:46), the specimens from south of Arteaga are like those from the Tepalcatepec Valley in scutellation and coloration, and not like Cnemidophorus lineatissimus lividus from the geographically closer coastal lowlands.
In the Tepalcatepec Valley Cnemidophorus lineatissimus exoristus inhabits gallery forests along the larger streams; in this habitat it is associated with Ameiva undulata sinistra. From the other species of Cnemidophorus in Michoacán, C. lineatissimus exoristus can be distinguished by the possession of seven longitudinal stripes in adults and by the characters of scutellation given in Table 5.
Cnemidophorus lineatissimus lineatissimus Cope
Cnemidophorus lineatissimus Cope, Proc. Amer. Philos. Soc., 17:94, 1877.—Colima and Guadalajara. Type locality restricted to Colima, Colima, México, by Smith and Taylor (1950b:179).
Cnemidophorus lineatissimus lineatissimus, Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:41, February 10, 1960.
Boca de Apiza (4).
These specimens have 117 to 126 dorsal granules at midbody, a noticeably lower count than that for Cnemidophorus lineatissimus lividus on the coast of Michoacán, which has 126 to 164 (148). Apparently these specimens represent immature C. lineatissimus lineatissimus; the differences between these and C. lineatissimus lividus from nearby localities indicate that possibly the populations are distinct species and not subspecies, as suggested by Duellman and Wellman (1960:41).
Cnemidophorus lineatissimus lividus Duellman and Wellman
Cnemidophorus lineatissimus lividus Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:50, February 10, 1960.—Maruata, Michoacán, México.
Barranca de Bejuco (4); Boca de Apiza (2); Coahuayana (6); El Ticuiz (7); La Placita (11); Maruata (7); Motín del Oro; Ostula (5); Playa Azul (4); Playa Cuilala (2); Pómaro (2); Salitre de Estopila (2); San Pedro Naranjestila.
This is the most abundant and widespread species of Cnemidophorus on the coastal lowlands of Michoacán, where it ranges from sea level to elevations of about 500 meters. In this area it inhabits dense arid scrub forest and semi-deciduous broad-leafed forest. Both of these habitats are continuous, or nearly so, along the lowlands and foothills of the Sierra de Coalcomán. This in itself may explain the abundance of Cnemidophorus lineatissimus and the relative scarcity of C. deppei and C. communis in the coastal area, for C. deppei and C. communis usually inhabit more open arid scrub forest, as occurs in the Tepalcatepec Valley. Living in the dense scrub forest with C. lineatissimus is Ameiva undulata sinistra.
Cnemidophorus scalaris Cope
Cnemidophorus gularis scalaris Cope, Trans. Amer. Philos. Soc., 17:47, 1892.—Chihuahua, Chihuahua, México.
Cnemidophorus scalaris, Zweifel, Bull. American Mus. Nat. Hist., 117:72, 1959.
Araro (2); Jacona; Lago de Cuitzeo (42); Morelia; 21 km. N of Morelia (4).
Zweifel (1959a:72) assigned the small species of Cnemidophorus having a relatively low number of dorsal granules and inhabiting the southern part of the Mexican Plateau to C. scalaris, which he diagnosed as rarely exceeding 100 mm. in snout-vent length and always having an average of less than 100 dorsal granules at midbody and usually less than 90. Forty-two specimens from the south shore of Lago de Cuitzeo (UMMZ 119558) have 80-91 (85.8) dorsal granules. Four specimens from 21 kilometers north of Norelia (UIMNH 6952 and UMMZ 104743) have 89, 78, 92, and 84 granules; one from Morelia (UMMZ 104742) has 78; two from Araro (UMMZ 119522) have 80 and 87; one from Jacona (UIMNH 24703) has 88.
Since no large adult males are present in the series from Michoacán, an adequate comparison of coloration between these and populations on the northern part of the Mexican Plateau cannot be made. Cnemidophorus scalaris is a name applied to the lizards inhabiting the Mexican Plateau from Chihuahua south to Puebla by Zweifel (1959a:72). It is doubtful if all of the populations assigned to this subspecies belong there; possibly more than one species is involved, but the paucity of material prevents further analysis at this time.
Heloderma horridum horridum (Wiegmann)
Trachyderma horridum Wiegmann, Isis von Oken, 22:421, 1829.—México. Type locality restricted to Huajintlán, Guerrero, México, by Smith and Taylor (1950b:193).
Heloderma horridum horridum, Bogert and Martín del Campo, Bull. Amer. Mus. Nat. Hist., 109:20, April 16, 1956.
Apatzingán; Coalcomán; La Placita; Oropeo; Parácuaro.
This species is known from elevations of less than 1000 meters in the Tepalcatepec Valley, the Sierra de Coalcomán, and the coastal lowlands. Specimens from Coalcomán, La Placita, and Parácuaro came from areas of dense woods; those from Apatzingán and Oropeo might have come from patches of dense woods in the otherwise open scrub forest of the Tepalcatepec Valley.
Gerrhonotus imbricatus imbricatus Wiegmann
Gerrhonotus imbricatus Wiegmann, Isis von Oken, 21:379, 1828.—México. Type locality restricted to México, Distrito Federal, by Smith and Taylor (1950b:201).
Gerrhonotus imbricatus imbricatus, Dunn, Proc. Acad. Nat. Sci. Philadelphia, 88:475, October 20, 1936.
Acuaro de las Lleguas (9); Cerro Barolosa (4); Cerro Tancítaro (36); Dos Aguas (22); Paracho; Sierra Patamba; Tinguidín; Zacapu.
Specimens from the Sierra de Coalcomán are noticeably different from those inhabiting the mountains rising from the Mexican Plateau. Of 45 specimens from Cerro Tancítaro and adjacent areas on the Mexican Plateau and in the Cordillera Volcánica, 15 have twelve longitudinal rows of dorsal scales and 30 have fourteen rows. Of seven specimens from the state of México, 5 have twelve rows and 2 have fourteen; of nine specimens from central Veracruz, 8 have twelve rows and one has fourteen; of six specimens from Hidalgo, 5 have twelve rows and one has sixteen; of two specimens from Guanajuata, one has fourteen and the other has sixteen rows. All of the 35 specimens from the Sierra de Coalcomán have sixteen rows. Furthermore, these specimens have the superciliary row extended anteriorly, so that the anterior superciliary is in broad contact with the loreal. Specimens from Cerro Tancítaro have a shorter superciliary row, so that the anterior superciliary is not in broad contact with the loreal. These characters were used by Tihen (1949:220) to distinguish Gerrhonotus imbricatus ciliaris from G. imbricatus imbricatus. According to Tihen, the subspecies G. imbricatus ciliaris ranges from Guanajuato and Hidalgo northward to Chihuahua and Coahuila, whereas the nominal subspecies occurs from Michoacán and Hidalgo southward to Oaxaca. Specimens from the Sierra de Autlán in Jalisco are like those from Cerro Tancítaro; consequently, there seems to be no connection between the populations of G. imbricatus ciliaris in the mountains of the northern part of the Mexican Plateau with the ciliaris-like individuals found in the Sierra de Coalcomán. The acquisition and study of additional material from throughout the range of the species is necessary to clarify the picture of geographic variation. Until then, I prefer to consider all of the specimens from Michoacán as Gerrhonotus imbricatus imbricatus.
The largest specimen is a male having a snout-vent length of 136 mm. Two juveniles collected in July 24, 1960, have snout-vent lengths of 36 and 42 mm. A specimen having a snout-vent length of 127 mm. and a tail length of 145 mm. was regurgitated by a Crotalus pusillus, which had a body length of 550 mm.
Gerrhonotus imbricatus imbricatus is an inhabitant of coniferous forests. In the Cordillera Volcánica it occurs from 1500 to 3500 meters at the top of Cerro Tancítaro. In the Sierra de Coalcomán it occurs from 2100 to 2700 meters. On July 4, 1955, a pair was found in copulation beneath a pine log at 2700 meters on Cerro Barolosa. The male was lying on top of the female and was holding her head firmly in his jaws; the male's tail was curled under the female's tail, so that the cloacae were in contact.
Serpentes
Typhlops braminus (Daudin)
Eryx braminus Daudin, Hist.... des reptiles, 7:279, 1803.—Vazagapatam, India.
Typhlops braminus, Cuvier, Règne animal, ed. 2, 2:73, 1829.
Apatzingán; Arteaga.
Both specimens known from Michoacán were collected by Gadow in 1908. Peters (1954:20) remarked that the specimen from Arteaga probably does not indicate a rapid spreading of the species, which most likely was introduced into México at the time that vessels were stopping at Acapulco from the Philippines (Taylor, 1940b:444), but instead may indicate that pack trains from Acapulco passed through the Sierra de Coalcomán. The occurrence of this snake along a long-used camino substantiates this belief.
Leptotyphlops bressoni Taylor
Leptotyphlops bressoni Taylor, Copeia, No. 1:5, March 9, 1939.—Hacienda El Sabino, Michoacán, México.
El Sabino.
This species still is known definitely only from the type specimen collected on the lower slopes of the Cordillera Volcánica at the northern edge of the Tepalcatepec Valley. A specimen (now lost) reported from Aguililla by Cope (1887:63) possibly represents this species (see Smith and Taylor, 1945:21, and Peters, 1954:20).
Leptotyphlops gadowi Duellman
Leptotyphlops gadowi Duellman, Copeia, No. 2:93, May 29, 1956.—Apatzingán, Michoacán, México.
Apatzingán.
No additional specimens of this species have been collected since the species was described by Duellman (1956b:93). Data given with the specimen by Gadow indicate that it came from his camp above Apatzingán at an elevation of about 800 meters. Although the exact position of this camp is unknown, the lower slopes of the Cordillera Volcánica above Apatzingán usually support arid scrub forest at elevations below 1000 meters. Therefore, this species probably is an inhabitant of the arid scrub forest.
Leptotyphlops phenops bakewelli Oliver
Leptotyphlops bakewelli Oliver, Occ. Pap. Mus. Zool. Univ. Michigan, 360:16, November 20, 1937.—Paso del Río, Colima, México.
Leptotyphlops phenops bakewelli, Smith, Proc. U. S. Natl. Mus., 93:445, October 29, 1943.
La Placita (4); La Salada; Ostula.
The five specimens from the coastal lowlands are from elevations of less than 150 meters; these were collected by Peters (1954:20); the specimen from La Salada is from an elevation of 580 meters in the Tepalcatepec Valley. Peters (loc. cit.) remarked that the rostral and the tip of the tail that were described as white by Oliver (1937:17) actually are sulphur-yellow in life.
Loxocemus bicolor Cope
Loxocemus bicolor Cope, Proc. Acad. Nat. Sci. Philadelphia, 13:77, June 30, 1861.—La Unión, El Salvador.
Loxocemus sumichrasti Bocourt, Ann. Sci. Nat., ser. 6, 4:1, 1876.—Tehuantepec, Oaxaca, México.
Apatzingán (6); La Orilla; Lombardia.
As noted by Peters (1954:21), this species was not recorded from Michoacán by Smith and Taylor (1945:27), but Gadow (1930:30) collected a specimen at La Orilla in 1908. This specimen (BMNH 1914.1.28.124) is a male having 235 ventrals and 47 caudals, a dark brown dorsum, and cream-colored labials and venter. The anterior chin-shields are considerably longer than the scales bordering the chin-shields. In these characters this specimen agrees with the diagnosis of Loxocemus bicolor given by Taylor (1940c:447), who revived Loxocemus sumichrasti Bocourt. Of the six specimens from Apatzingán in the Tepalcatepec Valley, three males have 243 to 253 (246.6) ventrals and 44 to 45 (44.3) caudals; three females have 238 to 247 (244.0) ventrals and 42 to 44 (43.0) caudals. Certain characters of scutellation utilized by Taylor for separating L. bicolor and L. sumichrasti are inconsistent in this series. The chin-shields are longer than the adjacent scales, like those illustrated in L. bicolor by Taylor (op. cit., fig. 1). The relative lengths of the prefrontal and internasal sutures are subequal, or the prefrontal suture is slightly longer. Thus, in these characters of scutellation these snakes are like L. bicolor, but in coloration they are like L. sumichrasti; the dorsal color in life was an iridescent dark bluish gray, and the belly was pale gray or bluish gray.
The supposed differences in scutellation between L. bicolor and L. sumichrasti have been questioned by Woodbury and Woodbury (1944:360); these authors treated L. sumichrasti as a subspecies of L. bicolor. As pointed out by Zweifel (1959b:5), such an arrangement is not tenable, for, although individuals with each kind of color pattern have not been collected together at any one locality, the over-all geographic picture is one of sympatric distribution. Only snakes having the coloration of L. sumichrasti have been collected in the Balsas-Tepalcatepec Basin. I agree with Zweifel (loc. cit.) that on the basis of morphological similarities and sympatric distribution, L. bicolor and L. sumichrasti seem to be dimorphic phases of the same species, showing no more striking differences in coloration than Lampropeltis getulus californiae, a now classical example of pattern dimorphism in snakes.
In Michoacán, as in other parts of its range, Loxocemus bicolor inhabits arid scrub forest environments at low elevations.
Boa constrictor imperator Daudin
Boa imperator Daudin, Hist. nat.... des reptiles, 5:150, 1803.—México. Type locality restricted to Córdoba, Veracruz, México, by Smith and Taylor (1950a:347).
Boa constrictor imperator, Forcart, Herpetologica, 7:199, December 31, 1951.
Apatzingán (4); Coalcomán; El Sabino (2); La Placita; La Playa (2); Lombardia; Nueva Italia (2); Río Cachán; Río Marquez, 13 km. SE of Nueva Italia; Río Nexpa; Volcán Jorullo.
These specimens have come from a variety of habitats from elevations of less than 1,000 meters. The species seems to be equally abundant in the broad-leafed semi-deciduous forests of the coastal foothills and in the arid Tepalcatepec Valley. In the latter area most of the specimens were collected at night.
Coniophanes fissidens dispersus Smith
Coniophanes fissidens dispersus Smith, Proc. U. S. Natl. Mus., 91:106, November 13, 1941.—El Limoncito, Guerrero, México.
Arteaga.
Further collecting in southern Michoacán has failed to add additional material of this species, which is known in the state from the one specimen collected by Gadow in 1908. The species possibly ranges throughout the coastal foothills of the Sierra de Coalcomán. Peters (1954:21) described the specimen from Arteaga.
Coniophanes lateritius lateritius Cope
Coniophanes lateritius Cope, Proc. Acad. Nat. Sci. Philadelphia, 13:524, March 31, 1862.—Guadalajara, Jalisco, México.
Coniophanes lateritius lateritius, Smith and Grant, Herpetologica, 14:20, April 25, 1958.
Nineteen km. S of Arteaga.
The one specimen available from Michoacán of this apparently rare species was discussed by Wellman (1959:127), who pointed out that although the specimen was geographically intermediate between the subspecies C. l. lateritius (Jalisco and Nayarit) and C. l. melanocephalus (Morelos and Puebla), the specimen (UMMZ 118954) was like C. l. lateritius in scutellation and in color pattern differed from other known specimens of the species in having had in life a pale orange, instead of a brick-red, dorsum. Additional specimens from the Sierra de Coalcomán will be required in order to determine whether this specimen is a representative of an orange-colored population or merely is aberrant in coloration.
The present specimen is from an elevation of 900 meters in oak forest on the southern slopes of the Sierra de Coalcomán; other locality records for the species indicate that it inhabits broad-leafed forest in foothills from Nayarit to Puebla.
Conophis vittatus vittatus Peters
Conophis vittatus Peters, Monats. Akad. Wiss. Berlin, p. 519, 1860.—No type locality given. Type locality restricted to Laguna Coyuca, Guerrero, México, by Smith and Taylor (1950a:331).
Conophis vittatus vittatus, Smith, Jour. Washington Acad. Sci., 31:119, March 17, 1941.
Arteaga; Coalcomán (4); La Playa; 19 km. S of Tzitzio.
All specimens of this terrestrial snake have been collected in areas of scrub forest between 800 and 1100 meters above sea level. Since the species is known from the coastal regions of Guerrero and Colima, its absence from the cost of Michoacán is unexplainable; probably the lack of specimens from these areas is due solely to inadequate collecting.
Conopsis biserialis Taylor and Smith
Conopsis biserialis Taylor and Smith, Univ. Kansas Sci. Bull., 28 (2):333, November 12, 1942.—Ten miles west of Villa Victoria, México, México.
Capácuaro (5); Cerro San Andrés; Cherán; Ciudad Hidalgo; Macho de Agua (4): Pátzcuaro (8); Tancítaro (24); Uruapan (9); 24 km. SE of Zitácuaro (14).
This species is abundant in the coniferous forests at elevations from 1550 to 2800 meters throughout the Cordillera Volcánica; apparently it does not occur in the Sierra de Coalcomán.
On August 1, 1956, a copulating pair was found beneath a rock at Capácuaro.
One of the best characters to distinguish this species from Toluca lineata, which occurs with Conopsis throughout its range in Michoacán, is the presence of large, black ventral blotches in Conopsis biserialis, as contrasted with the two rows of small black spots in Toluca lineata.
Conopsis nasus Günther
Conopsis nasus Günther, Catalogue... snakes... British Museum, p. 6, 1858.—California (in error). Type locality restricted to Guanajuato, Guanajuato, México, by Smith and Taylor (1950a:330).
Carapan (2); Erongaricuaro; Maravatio (3); Morelia (2); Nahuatzen; Pátzcuaro (7); Tacícuaro (8); Tancítaro.
This species has been collected in oak, pine-oak, and fir forests at elevations of 1900 to 2450 meters on the mountains rising from the Mexican Plateau. It does not seem to be so abundant as Conopsis biserialis. Sufficient ecological data to determine differences in habitat between the two species have not been compiled.
Diadophis dugesi Villada
Diadophis punctatus dougesii Villada, La Naturaleza, 3:226, 1875.—Potreros de Balbuena, Distrito Federal, México.
Diadophis dugesii, Blanchard, Bull. Chicago Acad. Sci., 7:51, December 30, 1942.
Morelia (2); Pátzcuaro; Quiroga.
Apparently this snake is uncommon in Michoacán. It has been found only at elevations of 1900 to 2200 meters in pine and pine-oak forests on the mountains rising from the Mexican Plateau.
Dryadophis melanolomus stuarti Smith
Dryadophis melanolomus stuarti Smith, Proc. U. S. Natl. Mus., 93:418, October 29, 1943.—Acapulco, Guerrero, México.
Coahuayana; El Ticuiz; La Placita (3); Punto San Juan de Lima; Punto San Telmo.
The few specimens indicate that in Michoacán, as elsewhere on the Pacific coast of México, this species is restricted to forested regions on the coastal plain. It does not occur in the Tepalcatepec Valley.
The coloration, in life, of a juvenile (UMMZ 114604) is as follows: The dorsum is uniform pale grayish tan on posterior one-third of body and on tail; anteriorly there are pale grayish tan middorsal blotches separated by grayish white interspaces, which are about one-half the length of the blotches. Posteriorly the blotches are less distinct, fading into the uniform grayish tan ground color of the posterior part of the body. The blotches extend laterally onto the fourth and fifth scale rows. Large squarish lateral intercalary blotches of darker brown interconnect with the dorsal blotches. The top of the head is pale olive-brown; a dark brown postorbital stripe extends from the eye to the posterior edge of the last upper labial. The labials, chin, and ventrals 1-30 are creamy white, changing to a dusty cream-color posteriorly; the chin and ventrals 1-30 are heavily spotted with dark brown. The iris is a cream-color above and chocolate brown below; the tongue is blue.
Drymarchon corais rubidus Smith
Drymarchon corais rubidus Smith, Jour. Washington Acad. Sci., 31:474, November 11, 1941.—Rosario, Sinaloa, México.
Apatzingán (5); Arroyo El Salto; Arteaga; Capirio; El Sabino (7); La Palma; La Placita; Ostula; San Juan de Lima.
Not all of the specimens from Michoacán are typical in color pattern of this subspecies, as defined by Smith (1941a:475). All specimens from the Tepalcatepec Valley are uniformly black above; they have reddish or cream-colored chins and the anterior two-thirds of the belly salmon-pink or reddish buff. Individuals from the Sierra de Coalcomán (Arteaga and Arroyo El Salto) are like those from the Tepalcatepec Valley. Three specimens from the coastal lowlands differ noticeably in color pattern:
UMMZ 104504, adult male (Ostula).—Pale brown above flecked with black anteriorly; at midbody, flecks form narrow transverse bands that become progressively wider posteriorly, until on tail no brown pigment evident, all ventrals reddish buff, except last eight, which are black.
UMMZ 104602, adult female (La Placita).—Black above, reddish cross-bands and flecks on all of body; dorsal and ventral surfaces of tail black; chin cream-color and entire belly reddish buff.
UMMZ 114626, adult male (San Juan de Lima).—Black above; dull rust-colored cross-bands on anterior half of body; chin white; belly rust-colored on anterior two-thirds of body and black posteriorly.
One specimen from La Palma on the Mexican Plateau (KU 29275) has the top of the head an olive-color, the entire dorsum black, the chin and ventrals 1-42 a cream-color, remainder of venter black, and all of the labials heavily barred with black. A juvenile from Capirio in the Tepalcatepec Valley (UMMZ 114627) is black above and has pale olive-colored flecks on the anterior one-third of the body; the top of the head is dark olive-brown, and the sides of the head are somewhat paler. Anteriorly the belly is a cream-color; posteriorly it is black.
The specimens from the Tepalcatepec Valley are typical of Drymarchon corais rubidus. Those from the coastal lowlands differ in having large areas of brown or red pigment on the dorsum, a condition not mentioned by Smith in his description of the subspecies. The specimen from La Palma, like many others from various localities on the Mexican Plateau, resembles in certain characters D. corais orizabensis (Smith, op. cit.: 477). Our knowledge of the geographical variation in coloration in this species is incomplete; many populations have been assigned to subspecific rank without justification.
In Michoacán this species is found from sea level to 1350 meters in the Sierra de Coalcomán and to 1300 meters at La Palma on Lago de Chapala. It has been collected in scrub forest, semi-deciduous broad-leafed forest, and oak forest.
Drymobius margaritiferus fistulosus Smith
Drymobius margaritiferus fistulosus Smith, Proc. U. S. Natl. Mus., 92:383, November 5, 1942.—Miramar, Nayarit, México.
Apatzingán (3); Coahuayana; Coalcomán (3); El Sabino (3); El Ticuiz; 12 km. S of Tzitzio.
This snake is abundant in the lowlands of the state; the few specimens listed above are indicative not of the rarity, but rather of the speed and agility, of this diurnal snake. It most frequently is found near water, where there is a dense growth of vegetation. One individual was observed in a large pool inhabited by several small Rana pipiens, and another was seen along the bank of a hyacinth-choked river channel. A third individual was captured while it was in pursuit of a Cnemidophorus.
This species has been collected on the coastal lowlands and seaward foothills of the Sierra de Coalcomán and in the Tepalcatepec Valley to elevations of 1150 meters.
Elaphe triaspis intermedia (Boettger)
Pityophis intermedius Boettger, Ber. Offen. Vereins. Naturk., 22:148, 1883.—México. Type locality restricted to Hacienda El Sabino, Michoacán, México, by Dowling (1960:74).
Elaphe triaspis intermedia, Mertens and Dowling, Senckenbergiana, 33:201, November 15, 1952.
Twenty-four km. E of Apatzingán; Chupio; El Sabino (4); 11 km. E of Emiliano Zapata.
Dowling (1960) has shown that specimens from the Balsas-Tepalcatepec Basin have fewer ventrals and caudals than those from the Sierra del Sur or the coast. All specimens from Michoacán were collected in open forest, either scrub or oak forest. They were found in drier situations than those described for the species in southern Tamaulipas by Martin (1958:69). In Michoacán Elaphe triaspis intermedia is known from the Tepalcatepec Valley, the lower slopes of the Cordillera Volcánica, and the western edge of the Mexican Plateau at an elevation of 1350 meters. It probably occurs in the lower parts of the Sierra de Coalcomán and along the Pacific coast, for it is known from the coastal lowlands of Guerrero and Colima. In August, 1951, I saw a snake that probably was this species in Barranca de Bejuco.
Enulius unicolor (Fischer)
Geophis unicolor Fischer, Abh. Nat. Ver. Bremen, 7:227, 1882.—México. Type locality restricted to Chilpancingo, Guerrero, México, by Smith and Taylor (1950a:331).
Enulius unicolor, Taylor and Smith, Univ. Kansas Sci. Bull., 25:247, July 10, 1939.
Between Ario de Rosales and La Playa; Coalcomán; Jungapeo (4); between Zitácuaro and Tuxpan.
This small snake has been collected from beneath rocks in brushy areas and broad-leafed forest between 900 and 1800 meters; it has not been found in coniferous forest. The limited ecological data suggest that the species inhabits the transition zone between the tropical scrub forest and the temperate hardwood forest.
All of the specimens have 17 rows of scales; four males have 169-178 (174.2) ventrals and 102-111 (106.8) caudals; two females have 192 and 195 ventrals and 96 and 87 caudals. Three individuals have one postocular on one side and two on the other; in the other specimens there are two postoculars on each side. The largest male has a body length of 232 mm. and a tail length of 130 mm.; the largest female has a body length of 274 mm. and a tail length of 119 mm.
Geagras redimitus Cope
Geagras redimitus Cope, Jour. Acad. Nat. Sci. Philadelphia, ser. 2, 8:141, 1876.
San Juan de Lima (2).
Previously this species was known definitely only from the Plains of Tehuantepec, Oaxaca. Sphenocalamus lineolatus was described by Fischer (1883:5) from Mazatlán; this name has been placed in the synonymy of Geagras redimitus Cope. Although Fischer gave the type locality only as "Mazatlán" and did not designate the state, it is probable that the type originated from Mazatlán, Sinaloa. The present specimens are from a locality almost midway between Tehuantepec and Mazatlán and support the possibility that Geagras ranges along the Pacific coast of México from Oaxaca to Sinaloa.
The two specimens from Michoacán (UMMZ 114446-7), both males, have 118 and 122 ventrals, 31 and 33 caudals, body lengths of 108 and 81 mm., and tail lengths of 20 and 15 mm. Both have 1-1 preoculars, 1-1 postoculars, 1-2 temporals, 6-6 upper labials, and 5-5 lower labials. In life, the dorsum was pale tan; the top of the head and the middorsal and lateral stripes were dark brown; the belly was white. The occipital spots were pale pinkish tan. Both specimens were found beneath rocks in tropical semi-deciduous forest at an elevation of 15 meters on the coastal plain.
Geophis dugesi Bocourt
Geophis dugesii Bocourt, Miss. Scientifique au Mexique et dans l'Amerique Centrale, Rept., livr. 9:573, 1883.—Tangancícuaro, Michoacán, México.
Carapan; Tangancícuaro; Zacapu.
Aside from the three specimens listed above, there are two (SU 4407-8) bearing the data "Michoacán." Bocourt (1883:574) stated that the type specimen from Tangancícuaro had six or seven pale cross-bands on the anterior part of the body. An illustration, presumably of the same specimen, by Dugès (1884:Pl. 9) shows five distinct and one indistinct cross-bands. Of the four specimens that I have examined, none has more than three pale cross-bands, and one has only one indistinct cross-band. Two females have 154 and 158 ventrals and 38 and 37 caudals; two males have 150 and 151 ventrals and 43 and 42 caudals.
This species is known only from elevations between 1750 and 2050 meters on the southwestern edge of the Mexican Plateau in the state of Michoacán.
Geophis incomptus Duellman
Geophis incomptus Duellman, Occ. Pap. Mus. Zool. Univ. Michigan, 605:3, May 29, 1959.—Dos Aguas, Michoacán, México.
Dos Aguas (15).
This species, which seems to be related to Geophis maculiferus, is known only from the pine-oak forest in the vicinity of Dos Aguas (elevation 2100 meters) in the Sierra de Coalcomán. Aside from the five specimens comprising the type series, there are ten other specimens in the Museum of Zoology at the University of Michigan collected by Floyd L. Downs in July, 1960. Data from these specimens and those comprising the type series show that in this sample seven males have 146-153 (149.3) ventrals and 35-37 (36.0) caudals; eight females have 150-154 (152.4) ventrals and 29-34 (32.5) caudals. The largest specimen is a female with a body length of 344 mm. and a tail length of 53 mm.
Geophis maculiferus Taylor
Geophis maculiferus Taylor, Univ. Kansas Sci. Bull., 27:119, December 30, 1941.—Near Cicio [sic] = Tzitzio, Michoacán, México.
Tzitzio.
The type and only known specimen of Geophis maculiferus (UIMNH 25078) is a female having 140 ventrals and 30 caudals, dorsal scales in 15 rows, one postocular, and an anterior temporal. Only one other species in México has dorsal scales in 15 rows and has an anterior temporal; that species is G. incomptus, which differs from G. maculiferus in having six or seven lower labials, instead of five, and in having the edges of the ventrals dark, instead of a uniformly cream-colored belly.
The locality from which the specimen was obtained lies at an elevation of 1630 meters on the southern slope of the Cordillera Volcánica. At that elevation there is an interdigitation of arid tropical scrub forest and pine-oak forest; probably Geophis maculiferus inhabits the pine-oak forest.
Geophis nigrocinctus Duellman
Geophis nigrocinctus Duellman, Occ. Pap. Mus. Zool. Univ. Michigan, 605:1, May 29, 1959.—Dos Aguas, Michoacán, México.
Dos Aguas (3).
The three specimens comprising the type series of the species were found beneath logs and in a stump in pine-oak forest at an elevation of 2100 meters. A discussion of the variation in these specimens and of probable relationships of the species was given by Duellman (1959). Floyd Downs spent several days at Dos Aguas in July, 1960; although he found ten specimens of Geophis incomptus, no further specimens of G. nigrocinctus were obtained.
Geophis petersi Boulenger
Geophis petersii Boulenger, Catalogue Snakes... British Museum, 2:321, September 23, 1894.—Mexico City. Type locality restricted to Pátzcuaro, Michoacán, México, by Smith and Taylor (1950a:335).
Cherán; Coalcomán; Morelia; Pátzcuaro (6).
This seems to be the most widespread species of Geophis in Michoacán. It has been found at elevations between 950 and 2350 meters, chiefly in pine or pine-oak forest. Boulenger (1894:321) described Geophis petersi from a specimen stated to be from Mexico City, a locality which probably is in error. The only localities from which the species is definitely known are those listed in this account.
Three males and five females from the Mexican Plateau and the Cordillera Volcánica have respectively 140-144 (141.7) and 143-151 (146.0) ventrals and 39-41 (40.0) and 29-35 (33.2) caudals. All have dorsal scales in 15 rows, 1 postocular, no anterior temporal, and a relatively small triangular supraocular. The specimen from Coalcomán (UMMZ 104698) was referred to Geophis nasalis by Peters (1954:22). This specimen is abnormal in several characters; in five places there is a fusion and separation of the vertebral and paravertebral scale rows, producing a change from 17 to 15 rows of dorsal scales. Fusion of the three rows takes place at the level of the 8th, 41st, 47th, 54th, and 65th ventrals. Furthermore, there is a small secondary postocular on each side of the head. In other characters the specimen is like G. petersi; the resemblances to that species are greater than to G. nasalis, which has been recorded from Guatemala and southern Chiapas.
Geophis tarascae Hartweg
Geophis tarascae Hartweg, Occ. Pap. Mus. Zool. Univ. Michigan, 601:1, May 4, 1959.—Uruapan, Michoacán, México.
Uruapan (3).
A female of this species was collected in the Parque Nacional at the north edge of Uruapan in 1899, and a male was taken there in 1947; these specimens were used by Hartweg in his description of the species. Floyd L. Downs obtained another specimen in the Parque Nacional on July 19, 1960. It has 164 ventrals and 46 caudals; in life, the ground color of the neck was brown with a purplish tint; the dorsal markings were black; the chin was a cream-color, and the belly was white. This specimen is distinguished from those of all other species of Geophis in Michoacán in that it has dark irregular cross-bars on the dorsum and a row of dark spots on the venter.
Hypsiglena torquata ochrorhyncha Cope
Hypsiglena ochrorhyncha Cope, Proc. Acad. Nat. Sci. Philadelphia, 12:246, November 15, 1860.—Cape San Lucas, Baja California, México.
Hypsiglena torquata ochrorhyncha, Bogert and Oliver, Bull. Amer. Mus. Nat. Hist., 83:378, March 30, 1945.
Tupátaro.
The systematic status of the geographic variants of Hypsiglena in México and southwestern United States has been commented on by several authors. Tanner (1944) considered H. torquata and H. ochrorhyncha to be distinct species; Bogert and Oliver (1945:379) and Duellman (1957b:238) presented evidence indicating that H. torquata and H. ochrorhyncha intergrade in Sinaloa and southern Sonora. In Hypsiglena the scutellation, including the numbers of labials, dorsals, ventrals, and caudals, seem to vary in a clinal manner. Nevertheless, these snakes can be divided into two distinct populations on the basis of the nuchal color pattern, consisting of an ochrorhyncha-type (a broad dark nape-band, the lateral edges of which extend anteriorly and fuse with a postorbital stripe, and a narrow nape stripe extending from the posteromedian edges of the parietals to the dark nape band) and a torquata-type (a somewhat narrower dark nape-band bordered anteriorly by a pale nuchal area, and no dark nape stripe). Snakes having the ochrorhyncha-type of nuchal pattern are found on the Mexican Plateau from Michoacán northward into the desert regions of Sonora and the southwestern United States. Snakes having the torquata-type of pattern are found on the coastal lowlands and adjacent slopes of the Sierra Madre Occidental from southern Sinaloa to Colima and thence inland in the Balsas-Tepalcatepec Basin to Morelos and Guerrero. An exception is Hypsiglena torquata dunklei from Forlón and San Fernando, Tamaulipas; it has the torquata-type of nuchal pattern. The distributional picture is somewhat complicated because some individuals having the torquata-type of nuchal pattern also have a faint nape stripe. If these are taken as exceptions, the general picture of distribution in México is H. t. torquata on the Pacific lowlands from Sinaloa southward to the Balsas Basin and H. t. ochrorhyncha on the Mexican Plateau.
Smith (1943:433) resurrected Hypsiglena jani Dugès for the snakes of the ochrorhyncha-type on the southern part of the Mexican Plateau. He stated that the southern specimens differed from northern ones in having a nuchal spot 9 or 10 scales in length, as compared with a spot 2 to 6 scales in length in northern specimens. A cursory examination of specimens from the areas between Arizona and Michoacán showed that there is a gradual increase in the size of the spot from north to south. If no other characters can be found to distinguish the populations, they should be considered as a single subspecies.
Hypsiglena affinis differs from H. torquata in possessing 19 instead of 21 rows of dorsal scales. Additional material is needed from the western slopes of Jalisco and the Barrancas in Zacatecas and Durango, before definite allocation of affinis can be made.
Bogert and Oliver (1945:379) discussed the status of certain named populations in Baja California and concluded that only one species occurs there, and that the species probably is conspecific with H. torquata. A careful review of the genus Hypsiglena might show that there is only one species.
The one specimen from Michoacán (USNM 46513) is from an elevation of about 2300 meters near the southern edge of the Mexican Plateau.
Hypsiglena torquata torquata (Günther)
Leptodeira torquata Günther, Ann. Mag. Nat. Hist., ser. 3, 5:170.—Laguna Island, Nicaragua (in error).
Hypsiglena torquata torquata, Taylor, Univ. Kansas Sci. Bull., 25:371, July 10, 1939.
Apatzingán; Capirio; Cofradía.
Specimens from the three mentioned localities have the dark nuchal spot bordered anteriorly by a pale blotch. In life the specimen from Capirio (UMMZ 114424) had rich reddish brown dorsal spots; the dorsal ground color was grayish white above and somewhat more gray laterally. The pale nuchal area was a cream-color, and the iris was grayish red.
All of the specimens were found in the arid scrub forest in the Tepalcatepec Valley at elevations between 200 and 350 meters.
Imantodes gemmistratus gracillimus (Günther)
Dipsas gracillima Günther, Biol. Centrali-Americana, Rept., p. 177, July, 1895.—southern México. Type locality restricted to Acapulco, Guerrero, México, by Smith and Taylor (1950a:331).
Imantodes gemmistratus gracillimus, Zweifel, Amer. Mus. Novitates, 1961:12, September 16, 1959.
La Orilla.
The specimen from La Orilla was reported by Peters (1954:23) as Imantodes gemmistratus oliveri; Zweifel (1959c) showed that I. g. oliveri did not range west of Tehuantepec and that the snakes inhabiting the coastal lowlands of Guerrero, Michoacán, and Colima were assignable to the subspecies gracillimus. It may be assumed that this subspecies ranges throughout the coastal lowlands and foothills of the Sierra de Coalcomán.
Imantodes gemmistratus latistratus (Cope)
Dipsas gemmistrata latistrata Cope, Bull. U. S. Natl. Mus., 32:68, 1887.—Southern Jalisco. Type locality restricted to Guadalajara, Jalisco, México, by Smith and Taylor (1950a:334).
Imantodes gemmistratus latistratus, Zweifel, Amer. Mus. Novitates, 1961:3, September 16, 1959.
El Sabino.
The one specimen from Michoacán was collected near the upper limits of the scrub forest on the slopes of the Cordillera Volcánica. Zweifel (1959c:10) stated that in certain aspects of coloration this specimen was like I. gemmistratus gracillimus, but in scutellation and other features of coloration it was like I. g. latistratus. There are too few specimens of this species to define the ranges of the various subspecies with any degree of accuracy, but from the limited number of specimens available, it seems that I. gemmistratus gracillimus occurs on the Pacific lowlands from Guerrero northward to Colima. Northward on the Pacific lowlands from Colima to Sinaloa and in the Balsas-Tepalcatepec Basin is found I. gemmistratus latistratus.
Lampropeltis doliata (Linnaeus)
Coluber doliatus Linnaeus, Systema naturae, ed. 12, 1:379, 1766.—Charleston, South Carolina.
Lampropeltis doliata, Klauber, Copeia, No. 1:11, April 15, 1948.
Coalcomán (3); El Sabino; 24 km. W of Morelia; Río Nexpa; Uruapan.
The few specimens of this species from Michoacán show a wide range of variation; furthermore, the present systematic status of the subspecies of Lampropeltis doliata portrays an incongruous pattern of distribution. Specimens from the Sierra de Coalcomán have relatively narrow red bands that are not interrupted dorsally by extensions of the black rings; the scales in the red bands have black tips. The specimen from El Sabino (EHT-HMS 5253) and the one from the Río Nexpa on the coast (USNM 31491) have broader red bands; the scales in the red bands do not have black tips. A specimen from 24 kilometers west of Morelia (UIMNH 17782) and one from Uruapan (UMMZ 121508) have the red bands interrupted dorsally by extensions from the black rings.
Specimens from the Sierra de Coalcomán were referred to L. doliata blanchardi by Peters (1954:24), who noted that in some characters these snakes were like L. d. nelsoni and in others like L. d. polyzona. The individual from El Sabino was referred to L. d. nelsoni by Taylor (1940c:465); the one from 24 kilometers west of Morelia was referred to L. d. arcifera by Smith (1942c:198). If these assignments are correct, three subspecies of Lampropeltis doliata occur in Michoacán: blanchardi in the Sierra de Coalcomán, nelsoni on the coast and in the Tepalcatepec Valley, and arcifera on the Mexican Plateau and in the Cordillera Volcánica. Such a distribution is plausible, but the few specimens and our general lack of knowledge of the variation and relationships of the different populations do not permit a definite assignment at this time.
Lampropeltis ruthveni Blanchard
Lampropeltis ruthveni Blanchard, Occ. Pap. Mus. Zool. Univ. Michigan, 81:8, April 28, 1920.—Pátzcuaro, Michoacán, México.
Morelia; Pátzcuaro; Tacícuaro.
At the present time this species is known definitely from only three localities on the Mexican Plateau in Michoacán. An incomplete skin from El Sabino (EHT-HMS 5438) was referred to this species by Taylor (1940c:465); the specimen cannot be found, so verification of the identification cannot be made at this time.
Leptodeira latifasciata (Günther)
Hypsiglena latifasciata Günther, Biologia Centrali-Americana, Reptilia, p. 138, October, 1894.—Southern México. Type locality restricted to Huajintlán, Morelos, México, by Smith and Taylor (1950a:331).
Leptodeira latifasciata, Dunn, Proc. Natl. Acad. Sci., 22:696, December, 1936.
Apatzingán; El Sabino; La Playa; 32 km. E of Nueva Italia.
This nocturnal snake apparently ranges throughout the arid Balsas-Tepalcatepec Valley to elevations of about 1050 meters. It has been collected only in the arid scrub forest. Aside from the specimens listed by Duellman (1958a:93), there is one (UMMZ 120223) having eight body blotches, a body length of 510 mm. and a tail length of 103 mm.
Leptodeira maculata (Hallowell)
Megalops maculatus Hallowell, Proc. Acad. Nat. Sci. Philadelphia, 13:488, March 31, 1862.—"Tahiti." Type locality restricted to Manzanillo, Colima, México, by Duellman (1958a:54).
Leptodeira maculata, Duellman, Bull. Amer. Mus. Nat. Hist., 114:53, February 24, 1958.
Aguililla (2); Apatzingán (24); Arteaga (2); Capirio (3); Charapendo (2); Coahuayana (3); Cofradía; Cuatro Caminos; La Placita (3); Lombardia (69); Nueva Italia (29); Pómaro; Río Marquez, 10 km. S of Lombardia (2); Salitre de Estopila; Tafetan (2); Volcán Jorullo.
This snake is abundant in the arid Tepalcatepec Valley; most of the specimens have been collected in arid scrub forest at elevations of less than 500 meters. With the onset of the rains in late June and early July, large numbers of these snakes can be found around temporary pools, where they feed on small frogs and toads. In the dry season few individuals were found, and all of those were beneath cover. Specimens from the coast have more body-blotches than do those from the Tepalcatepec Valley (Duellman, 1958a:56); otherwise the snakes show little variation.
Leptodeira splendida bressoni Taylor
Leptodeira bressoni Taylor, Univ. Kansas Sci. Bull., 25:321, July 10, 1939.—Hacienda El Sabino, Michoacán, México.
Leptodeira splendida bressoni, Duellman, Bull. Amer. Mus. Nat. Hist., 114:84, February 24, 1958.
Coalcomán (3); El Sabino (3); Uruapan (5).
The range of Leptodeira splendida bressoni apparently does not overlap that of Leptodeira maculata; the latter is restricted to the lower reaches of the arid scrub forest, whereas L. s. bressoni inhabits the upper limits of the arid scrub forest and the lower part of the pine-oak forest. Specimens have been collected between 950 and 1630 meters on the slopes of the Cordillera Volcánica and at 950 meters in the Sierra de Coalcomán. At Uruapan individuals were found beneath rocks along a stream and in a stone fence. Leptodeira duellmani, which was described from Coalcomán by Peters (1954:25), is an aberrant individual of L. s. bressoni (Duellman, 1958a:56).
Leptophis diplotropis (Günther)
Ahaetulla diplotropis Günther, Ann. Mag. Nat. Hist., ser. 4, 9:25, 1872.—Tehuantepec, Oaxaca, México.
Leptophis diplotropis, Bocourt, Mission scientifique au Mexique et dans l'Amerique Centrale, Reptiles, livr. 15:835, 1897.
Between Aguililla and Dos Aguas; Arteaga; Coalcomán; El Diezmo; El Sabino (5); La Playa; Ocorla.
Most specimens of this species have been collected in tropical semi-deciduous forest at elevations of less than 1000 meters. In the Sierra de Coalcomán one was taken in pine-oak forest at an elevation of 1700 meters near Ocorla; another was found in broad-leafed forest between Aguililla and Dos Aguas at an elevation of 1600 meters. Most individuals have been seen in trees or bushes. The absence of broad-leafed forest in the Tepalcatepec Valley probably accounts for the absence of this snake in that area.
Manolepis putnami (Jan)
Dromicus putnami Jan, Elenco sistematico degli Ofidi, p. 67, 1863.—San Blas, Nayarit, México.
Manolepsis putnami, Smith and Taylor, Bull. U. S. Natl. Mus., 187:92, October 5, 1945.
La Placita (3); Maquili; Ostula.
In Michoacán the species has been found only in tropical semi-deciduous forest on the lower slopes of the Sierra de Coalcomán. From the observations made by Peters (1954:28), this snake is diurnal and feeds on teiid lizards.
Masticophis striolatus striolatus Mertens
Coluber striolatus Mertens, Zoologica (Stuttgart), 32:190, 1934.—Substitute name for Coluber lineatus Bocourt, a secondary homonym of Coluber lineatus Linnaeus = Lygophis lineatus. Type locality restricted to Presidio de Mazatlán, Sinaloa, México, by Smith and Taylor (1950a:343).
Masticophis striolatus striolatus, Zweifel and Norris, Amer. Midl. Nat., 54:242, July, 1955.
Apatzingán (4); Arteaga; Coalcomán (3); El Sabino; Jiquilpan; La Palma; La Playa (3); Lombardia; Nueva Italia; Río Cachán; Santa Ana; Uruapan (2); Volcán Jorullo; Ziracuaretiro.
This large diurnal species inhabits open scrub forest and cultivated terrain from sea level to about 1650 meters. On the Mexican Plateau it is known from the area around Lago de Chapala, to which it possibly gained access through the valleys in the headwaters of the Tepalcatepec drainage. Specimens from southern Michoacán have been reported previously by Peters (1954:28) and Duellman (1954b:16) as Masticophis flagellum lineatus.
Masticophis taeniatus australis Smith
Masticophis taeniatus australis Smith, Jour. Washington Acad. Sci., 31:390, September 11, 1941.—Guanajuato, Guanajuato, México.
Tacícuaro (2); Zamora.
This species reaches the southern limit of its distribution in the state of Michoacán. The limited ecological data available suggest that the species inhabits the open mesquite grassland of the Mexican Plateau.
Oxybelis aeneus auratus (Bell)
Dryinus auratus Bell, Zool. Jour., 2:324, 1825.—México. Type locality restricted to Tehuantepec, Oaxaca, México, by Smith and Taylor (1950a:340).
Oxybelis aeneus auratus, Bogert and Oliver, Bull. Amer. Mus. Nat. Hist., 83:381, March 30, 1945.
Coahuayana; El Sabino (4); between Las Tecatas and Las Higuertas; between Los Pozos and La Ciénega; Playa Azul; Pómaro (2); between Pómaro and Maruata (2); Punto San Telmo; Río Tizupan.
On the basis of the number of specimens seen and collected on the seaward slopes of the Sierra de Coalcomán, this is a common snake there. Most specimens were collected in tropical semi-deciduous forest; others were collected in oak forest to an elevation of 1700 meters. Apparently Oxybelis does not inhabit the lower parts of the Tepalcatepec Valley; the only specimens from the inland area are four from El Sabino, which is situated at about 900 meters on the slopes of the Cordillera Volcánica. One individual was seen in gallery forest near Limoncito at an elevation of 730 meters on the northern slopes of the Sierra de Coalcomán.
Pituophis deppei deppei (Duméril)
Elaphis deppei Duméril, Mem. Acad. Inst. France, 23:453, 1835.—México. Type locality restricted to San Juan Teotihuacán, México, México, by Smith and Taylor (1950a:334).
Pituophis deppei deppei, Stull, Occ. Pap. Mus. Zool. Univ. Michigan, 250:1, October 12, 1932.
Carapan (2); Morelia; Tacámbaro; Tacícuaro; Zacapu.
Duellman (1960b) showed that the widespread species Pituophis deppei was composite and that the "lined subspecies" actually represented another species, Pituophis lineaticollis. Pituophis deppei occurs only on the Mexican Plateau; in Michoacán it inhabits mesquite grassland and oak-bunch grass associations between 1900 and 2200 meters.
Pituophis lineaticollis lineaticollis (Cope)
Arizona lineaticollis Cope, Proc. Acad. Nat. Sci. Philadelphia, 13:300, December 28, 1861.—Southern Mexican Plateau. Type locality restricted to 24 kilometers northwest of Oaxaca, Oaxaca, México, by Duellman (1960b:607).
Pituophis lineaticollis lineaticollis, Duellman, Univ. Kansas Publ. Mus. Nat. Hist., 10:607, May 2, 1960.
Acuaro de las Lleguas; Dos Aguas (3); Morelia; Tancítaro (5).
This species reaches the northern limits of its range in the Sierra de Coalcomán and on the Mexican Plateau in Michoacán. On the plateau it has been collected in mesquite grassland at elevations between 1500 and 2000 meters. In the Sierra de Coalcomán individuals were found in open pine-oak forest at 2100 meters elevation and in a meadow surrounded by pine-oak forest at 2300 meters.
Pseudoficimia frontalis (Cope)
Toluca frontalis Cope, Proc. Acad. Nat. Sci. Philadelphia, 16:167, September 30, 1864.—Colima, Colima, México.
Pseudoficimia frontalis, Günther, Biologia Centrali-Americana, Reptilia, p. 96, May, 1893.
Apatzingán; Coalcomán (6); El Sabino (2).
Most specimens were found beneath rocks in grassy areas near the upper limits of the arid scrub forest, both in the Sierra de Coalcomán and on the southern slopes of the Cordillera Volcánica; all are from elevations of less than 1100 meters. One specimen was found on a road at night near Apatzingán. This species has been found in similar habitats near Huajintlán, Guerrero, and in arid scrub forest at lower elevations in Colima. It is unknown from the coast of Michoacán.
Pseudoficimia pulcherrima Taylor and Smith
Pseudoficimia pulcherrima Taylor and Smith, Univ. Kansas Sci. Bull., 28:246, May 15, 1942.—Huajintlán, Guerrero, México.
Apatzingán.
This specimen (CNHM 39208) was reported by Schmidt and Shannon (1947:81); they stated that it was a paratype of P. pulcherrima. However, Taylor and Smith (1942a:246) did not mention the specimen; aside from the type (EHT-HMS 5497), the only other specimen they designated as belonging to the type series was UMMZ 85711 from Chilpancingo, Guerrero.
The taxonomic validity of Pseudoficimia pulcherrima remains doubtful, for only minor characters distinguish it from P. frontalis. Furthermore, all known specimens of P. pulcherrima are from within the geographic range of P. frontalis.
Rhadinaea hesperia hesperia Bailey
Rhadinaea hesperia Bailey, Occ. Pap. Mus. Zool. Univ. Michigan, 412:8, May 6, 1940.—Omilteme and Sierra de Burro, Guerrero. Type locality restricted to Omilteme, Guerrero, México, by Smith and Taylor (1950a:332).
Rhadinaea hesperia hesperia, Smith, Proc. Biol. Soc. Washington, 55:185, December 31, 1942.
Arteaga (3); Coalcomán; El Sabino (2); Uruapan; Volcán Jorullo (2).
One specimen from Volcán Jorullo (UMMZ 104494), three from Arteaga (UMMZ 119281), and one from Uruapan (UMMZ 92342) are typical of the subspecies R. h. hesperia in possessing a lateral cream-colored line on the sixth and parts of the fifth and seventh dorsal scale rows and in lacking a dark line on the second scale row. The specimens from El Sabino (EHT-HMS 5441 and UIMNH 18933) and one from Coalcomán (UMMZ 104502) have the cream-colored line on the sixth and adjacent parts of the fifth and seventh scale rows and have a dark line on the second scale row. Another individual from Volcán Jorullo (UMMZ 104682) has cream-colored lines like the others, but it possesses two lateral dark lines, one on the second scale row, and one on the third.
Smith (1942d:186) diagnosed Rhadinaea hesperia hesperioides as differing from the nominal subspecies in having the cream-colored line on the fourth and fifth scale rows and in possessing a dark line on the second scale row. The specimens seen all have the lateral cream-colored line centered on the sixth scale row, as is characteristic of R. h. hesperia. Although many of the specimens also possess a dark line on the second scale row, these specimens are here assigned to R. h. hesperia. Additional specimens are necessary to define accurately the subspecies and their ranges. Peters (1954:29) assigned the specimens from Coalcomán to R. h. hesperioides.
In life the specimens from Arteaga had bright cream-colored temporal stripes and dorsolateral stripes on the anterior part of the body. The chin and anterior one-sixth of the belly was white; posteriorly the venter was bright orange-red.
In Michoacán this snake has been found in tropical semi-deciduous forest, arid scrub forest, and pine-oak forest at elevations from 850 to 1500 meters.
Rhadinaea laureata (Günther)
Dromicus laureatus Günther, Ann. Mag. Nat. Hist., ser. 4, 1:419, 1868.—Mexico City.
Rhadinaea laureata, Boulenger, Catalogue Snakes... British Museum, 2, p. 179, September 23, 1894.
Capácuaro; Carapan (8); Cherán (3); Paracho (2); Pátzcuaro; Tancítaro (10).
This snake is abundant in the Cordillera Volcánica, but it is unknown in the mountains to the northeast of Morelia or in the Sierra de Coalcomán. Most specimens were found beneath volcanic rocks imbedded in the ashy soil in pine forest between 1800 and 2300 meters.
Rhadinaea taeniata (Peters)
Dromicus taeniatus Peters, Monats. Akad. Wiss. Berlin, p. 275, 1863.—México.
Rhadinaea taeniata, Bailey, Occ. Pap. Mus. Zool. Univ. Michigan, 412:14, May 6, 1940.
Tancítaro (2).
This species, which is known only from a small region in the mountains of Jalisco and central Michoacán, is represented by two specimens (CNHM 37130 and 39030) collected at Tancítaro (see Schmidt and Shannon, 1947:80).
Salvadora bairdi Jan
Salvadora Bairdii Jan. Icon. gener. ophid., livr. 2, pl. 3, fig. 2, 1860.—México. Type locality restricted to Acámbaro, Guanajuato, México, by Smith and Taylor (1950a:330).
Barranca Seca; Carapan; Cerro San Andrés; Cojumatlán (2); Jiquilpan; Morelia; Pátzcuaro (4); Quiroga; Sahuayo (2); Tacícuaro (12); Tancítaro (56); Uruapan (2); Zacapu (2); between Zitácuaro and Tuxpan (3).
This species is abundant on the Mexican plateau, where it inhabits the more grassy areas in the mesquite grassland and cutover land in the pine forests from 1550 to 2500 meters. Davis and Dixon (1957:21) described a specimen from Zacapu as having two dark paravertebral stripes diverging on the temporals and extending through the eye onto the loreal, a characteristic of Salvadora lineata. On the basis of this specimen, Davis and Dixon suggested that Salvadora bairdi and S. lineata were subspecifically related. The examination of the large number of specimens from Michoacán has revealed this kind of coloration in only one other specimen, an individual from Tacícuaro, in which the stripes diverge, but do not extend through the eye onto the loreal. Data on scutellation for the large series from Tancítaro were given by Schmidt and Shannon (1947:78), and for the series from Tacícuaro by Smith (1943:466).
Salvadora mexicana (Duméril, Bibron, and Duméril)
Zamenis mexicanus Duméril, Bibron, and Duméril, Erpétologie genérale, 7 (pt. 1), p. 695, 1854.—Cape Corrientes, Jalisco, México.
Salvadora mexicana Günther, Ann. Mag. Nat. Hist., ser. 3, 12:349, 1863.
Apatzingán (12); Capirio (2); El Sabino (5); Huetamo; La Placita; La Playa (4); Lombardia; Nueva Italia; Ojos de Agua de San Telmo; Oropeo; Río Cancita, 14 km. E of Apatzingán; Santa Ana.
This is one of the most abundant snakes in the arid lowlands of the Tepalcatepec Valley; observations indicate that it probably is equally abundant on the coastal lowlands. Near Apatzingán as many as five of these snakes have been seen in one-half hour. The snakes seem to be equally abundant and active in the dry season and in the rainy season. Most individuals were seen on the ground, but two were found in low trees. On several occasions Salvadora mexicana was observed in pursuit of lizards on the ground. Captured individuals regurgitated Cnemidophorus costatus zweifeli, Cnemidophorus deppei infernalis, Sceloporus horridus oligoporus, Sceloporus pyrocephalus, and Urosaurus gadowi.
Salvadora mexicana inhabits only the arid scrub forest at elevations from sea level to about 1000 meters.
Sibon nebulatus (Linnaeus)
Coluber nebulatus Linnaeus, Systema naturae, ed. 10, 1, p. 222, 1758.—Africa (in error). Type locality restricted to Jicaltepec, Veracruz, México, by Smith and Taylor (1950a:349).
Sibon nebulatus, Taylor, Univ. Kansas Sci. Bull., 26:473, November 27, 1940.
Aquila.
The one specimen from Michoacán was collected by Peters (1954:30) in tropical semi-deciduous forest on the coastal foothills of the Sierra de Coalcomán. As presently known, the range of this species in western México extends from Chiapas to Nayarit. Throughout this region the species avoids scrub forest; this may explain its absence in the Balsas-Tepalcatepec Valley.
Sonora michoacanensis michoacanensis (Dugès)
Contia michoacanensis Dugès, in Cope, Proc. Amer. Philos. Soc., 22:178, 1885.—Michoacán. Type locality restricted to Apatzingán, Michoacán, México, by Smith and Taylor (1950a:335).
Sonora michoacanensis michoacanensis, Stickel, Proc. Biol. Soc. Washington, 56:116, October 19, 1943.
Apatzingán (3); Coalcomán (3); 12 km. S of Tzitzio.
These specimens, together with all known specimens from the Sierra del Sur in Guerrero (KU 23790-1, MVZ 45123) and the upper Balsas Basin in Puebla (UIMNH 41688), are referable to S. m. michoacanensis. The dorsal pattern consists of a highly variable number of cross-bands of red, white, and black. In the specimens from Michoacán there are as many as 17 red cross-bands on the body. One specimen from Apatzingán (CNHM 37141) has just behind the head a white band, bordered on either side by a narrow black band; posteriorly the body is uniform red. Two specimens from Coalcomán (UMMZ 109905-6) have respectively 11 and 13 red cross-bands and 20 and 17 white cross-bands, and the posterior part of the body is devoid of red color. Other specimens from these localities have red, black, and white cross-bands throughout the length of the body.
Sonora michoacanensis michoacanensis is distinguished from S. michoacanensis mutabilis by the presence of cross-bands on the tail in the latter (Stickel, 1943:116). One specimen from Coalcomán (UMMZ 109904) has one narrow band on the tail; all others from Michoacán have uniformly red tails.
Apparently Sonora michoacanensis michoacanensis ranges in semi-arid and arid habitats from the upper Balsas Basin in Puebla westward to the lower slopes of the Sierra de Coalcomán, whereas S. m. mutabilis lives in foothills of the Sierra Madre Occidental from southern Jalisco to Nayarit. Zweifel (1959b:6) presented evidence to show that specimens of S. m. mutabilis supposedly from "Distrito Federal" probably bear erroneous locality data.
Tantilla bocourti (Günther)
Homalocranium bocourti Günther, Biologia Centrali-Americana, Reptilia, p. 149, 1895.—Guanajuato, Guanajuato, México.
Tantilla bocourti, Cope, Amer. Nat., 30:1021, December, 1896.
Carapan; Pátzcuaro (2); between Zitácuaro and Río Tuxpan (11).
This small snake is an inhabitant of the coniferous forests and the pine-oak forests on the Cordillera Volcánica. Data on the series from between Zitácuaro and the Río Tuxpan were given by Taylor (1940c:481).
Tantilla calamarina Cope
Tantilla calamarina Cope, Proc. Acad. Nat. Sci. Philadelphia, 18:320, February 13, 1867.—Guadalajara, Jalisco, México.
Apatzingán; La Placita.
Although this snake has been collected at high elevations along the rim of the Mexican Plateau in Nayarit, Jalisco, México, and Puebla, the specimens from Michoacán are from arid scrub forest at elevations of less than 400 meters. The species has been found in similar habitats in Colima (Oliver, 1937:24) and in Sinaloa and the Tres Marías Islands (Zweifel, 1960:110).
Toluca lineata lineata Kennicott
Toluca lineata Kennicott, in Baird, Report on the United States and Mexican boundary survey, 2, Reptiles, p. 23, 1859.—Valley of México.
Toluca lineata lineata, Taylor and Smith, Univ. Kansas Sci. Bull., 28:343, May 15, 1942.
Capácuaro; Carapan (12); Cherán (23); Cojumatlán; Los Reyes; Morelia (2); Nahuatzen; Paracho (10); Pátzcuaro (17); Uruapan (2).
This small snake is an inhabitant of the coniferous forests between elevations of about 1550 and 2800 meters. Not infrequently, individuals have been found in pine-oak forest within these elevations.
The generic status of Toluca is unsettled. Taylor and Smith (1942b) separated Toluca from Conopsis by the presence of enlarged and grooved posterior maxillary teeth in Toluca and their absence in Conopsis. Bogert and Oliver (1945:378) suggested synonymizing Toluca with Conopsis. Smith and Laufe (1945:12) defined the generic position of Toluca. Actually, in deciding the generic position of these snakes, five genera (Ficimia, Gyalopion, Pseudoficimia, Conopsis, and Toluca) must be considered. Of these Ficimia and Gyalopion are closely related; they have been placed in one genus by some workers. Pseudoficimia is intermediate between Ficimia-Gyalopion and Toluca-Conopsis. A workable definition of the supraspecific classification of these snakes must await a thorough review of the species.
Trimorphodon biscutatus biscutatus (Duméril, Bibron, and Duméril)
Dipsas biscutata Duméril, Bibron, and Duméril, Erpétologie genérale, 7 (pt. 2):1153, 1854.—México. Type locality restricted to Tehuantepec, Oaxaca, México, by Smith and Taylor (1950a:340).
Trimorphodon biscutatus biscutatus, Smith, Proc. U. S. Natl. Mus., 91:159, November 10, 1941.
Apatzingán (11); Cofradía; Cuatro Caminos; El Sabino (2); La Placita; La Playa (2); Lombardia (2); Nueva Italia (2); Río Tepalcatepec, 27 km. S of Apatzingán; Tafetán.
In the arid lowlands of the Tepalcatepec Valley and presumably also in the scrub forest of the coastal lowlands, this is an abundant snake, which is active only at night. Usually snakes of this species are found on the ground, but one large individual was observed at night in a low tree. That individual defied capture by widely opening its mouth and striking repeatedly at the collector. The excreta of one specimen contained feathers of an unidentified species of bird.
Trimorphodon latifascia Peters
Trimorphodon biscutata latifascia Peters, Monats. Akad. Wiss. Berlin, p. 877, 1869.—Puebla, México. Type locality restricted to Izúcar de Matamoros, Puebla, México, by Smith and Taylor (1950a:341).
Trimorphodon latifascia. Taylor, Univ. Kansas Sci. Bull., 25:364, July 10, 1939.
Apatzingán (5); Casada Tzararacua; Coalcomán (2); Lombardia; 14 km. S of Lombardia; Nueva Italia; San Salvador.
In Michoacán this species has been collected in semi-arid habitats at elevations from 300 to 1430 meters in the Tepalcatepec Valley and lower slopes of the Cordillera Volcánica. In this area it occurs sympatrically with Trimorphodon biscutatus biscutatus.
In life, adults have a pale tan dorsal ground color and rich chocolate brown cross-bands; the eye is pale grayish tan. A juvenile from Coalcomán has black cross-bands on a pale grayish tan ground color. As stated by Schmidt and Shannon (1947:83) and Peters (1954:32), the type specimen of Trimorphodon fasciolata Smith from Cascada Tzararacua is indistinguishable from specimens of Trimorphodon latifascia.
Seven males have 209 to 223 (216.5) ventrals; one female has 227 ventrals. The number of dark cross-bands on the body varies from 12 to 16 (13.5). The relationships of this species are with Trimorphodon tau on the Mexican Plateau. In fact, additional specimens from the headwaters of the Tepalcatepec Valley and the lower slopes of the Mexican Plateau in eastern Michoacán and adjacent Jalisco may show that the two are conspecific. Trimorphodon latifascia differs from tau in having fewer dark cross-bands on the body and in lacking an interocular bar.
Trimorphodon tau Cope
Trimorphodon tau Cope, Proc. Amer. Philos. Soc., 11:151, 1869.—Quiotepec, Oaxaca, México.
Emiliano Zapata (2); between Morelia and Ciudad Hidalgo; Tacícuaro; Tangamandapio.
Two of the specimens from Michoacán (UMMZ 118948 from Tangamandapio and UIMNH 19138 from Tacícuaro) have cream-colored, Y-shaped marks on the head. These markings supposedly are characteristic of Trimorphodon upsilon. One specimen from Emiliano Zapata (UMMZ 118950) and one from between Morelia and Ciudad Hidalgo (EHT-HMS 21402) have a cream-colored line on the parietal suture; in another specimen from Emiliano Zapata (UMMZ 118949) the anterior end of this line is expanded, giving the appearance of an incipient "Y". Thus, the nature of the markings on the head in specimens from Michoacán is intermediate between the typical condition in Trimorphodon tau and the usual condition in T. upsilon. Smith and Taylor (1945:148) gave the range of Trimorphodon tau as: "Central Guerrero, in the Sierra Madre del Sur; central Oaxaca; and the edge of the plateau in central Michoacán." They gave the range of Trimorphodon upsilon as: "Southern Chihuahua south to central Michoacán, east to central Hidalgo." Specimens referable to T. tau have been found at La Joya de Salas, near Ciudad Victoria, and near Llera, Tamaulipas (see Smith and Darling, 1952:85, and Martin, 1958:74). Some of these specimens also show combinations of characteristics of T. tau and T. upsilon. Smith and Darling (loc. cit.) suggested that T. tau and T. upsilon be considered as subspecies. However, if T. tau and T. upsilon are subspecies, intergrades would be expected between the ranges of the two populations and not on the northeastern and southwestern periphery of their combined ranges. Instead, the limited evidence now available suggests that T. tau and T. upsilon are names based on a highly variable character of color pattern of the head, and that only one species is involved.
In Michoacán this species inhabits the mesquite grassland on the Mexican Plateau.
Tropidodipsas occidentala Oliver
Tropidodipsas occidentala Oliver, Occ. Pap. Mus. Zool. Univ. Michigan, 360:20, November 20, 1937.—Comala, Colima, México.
Coalcomán.
This specimen was reported by Peters (1954:34), who found it beneath a rock at the mouth of a heavily wooded ravine near Coalcomán at an elevation of 950 meters. The only other known specimen is from Comala, Colima, a village, like Coalcomán, that is located near the upper limits of the arid scrub forest.
Natrix valida isabelleae Conant
Natrix valida isabelleae Conant, Nat. Hist. Misc., 126:7, September 15, 1953.—Pie de la Cuesta, Laguna Coyuca, Guerrero, México.
Coahuayana; Playa Azul (2); Punto San Juan de Lima.
Three females and one male have, respectively, 133, 135, 135, and 131 ventrals, and 68, 68, 73, and 75 caudals. The grayish stippling on the posterior ventral surfaces mentioned by Conant (1953:9) is not visible on these specimens. In the small individuals from Punto San Juan de Lima and from Coahuayana there are four longitudinal rows of dark spots on the dorsum; in two large females from Playa Azul the spots are barely discernible.
All of the specimens from Michoacán were found in the coastal lowlands; those from Playa Azul were collected from a small brackish, mangrove-lined lagoon.
Storeria storerioides (Cope)
Tropidoclonium storerioides Cope, Proc. Acad. Nat. Sci. Philadelphia, 17:190, December 26, 1865.—Mexican Plateau. Type locality restricted to Tres Cumbres, Morelos, México, by Smith and Taylor (1950a:336).
Storeria storerioides, Garman, Mem. Mus. Comp. Zool., 8(3):29, June, 1883.
Dos Aguas (11); Puerto de Garnica; Tancítaro (11); Tzitzio; Uruapan; 16 km. NW of Zacapu.
Three males and six females from the Sierra de Coalcomán have, respectively, 122-128 (125.3) and 126-136 (130.0) ventrals, and 46-47 (46.7) and 38-42 (39.1) caudals. Four males and eleven females from the Cordillera Volcánica have, respectively, 124-132 (128.5) and 127-139 (136.4) ventrals, and 43-48 (44.7) and 38-44 (40.2) caudals. These data show that, although there is little difference in the number of caudals, specimens from the Sierra de Coalcomán have fewer ventrals than do specimens from the Cordillera Volcánica. Of eleven specimens from the Sierra de Coalcomán, two have black bellies. Five others from the Sierra de Coalcomán and one from Puerto de Garnica in the Cordillera Volcánica have the bellies heavily stippled with black, giving a gray appearance. Melanistic tendencies in this species have been discussed by Anderson (1960:64), who examined the specimen from Tzitzio. In life, one specimen from Dos Aguas (UMMZ 119451) had a cream-colored belly; the edges of the ventrals were dark brick-red.
In Michoacán this snake inhabits pine-oak, pine, and fir forests at elevations between 1550 and 2800 meters in the Cordillera Volcánica and the Sierra de Coalcomán. Most specimens were found beneath rocks; the one from Tzitzio was removed from the stomach of a Mexican Motmot (Anderson, 1960:66).
Thamnophis dorsalis cyclides Cope
Thamnophis cyrtopsis cyclides Cope, Proc. Acad. Nat. Sci. Philadelphia, 13:299, December 28, 1861.—Cape San Lucas, Baja California (in error). Type locality restricted to Guanajuato, Guanajuato, México, by Smith and Taylor (1950a:330). Smith, Copeia, no. 2:140, June 8, 1951. Milstead, Texas Jour. Sci., 5:368, September, 1953.
Thamnophis eques eques (nec. Reuss), Smith, Zoologica, 27:106, October 23, 1942. Bogert and Oliver, Bull. Amer. Mus. Nat. Hist., 83:356, March 30, 1945.
Thamnophis vicinus Smith, Zoologica, 27:104, October 23, 1942.—Temazcal, Michoacán, México.
Thamnophis dorsalis cyclides, Fitch and Milstead, Copeia, no. 1:112, March 17, 1961.
Barolosa; Coalcomán; Dos Aguas (3); Los Reyes; Morelia (16); Opopeo; Pino Gordo; Tacícuaro (16); Tancítaro (14); Tangamandapio (2); Temazcal (2); Tzintzuntzan; Uruapan.
The snakes comprising the former Thamnophis eques-group have undergone extensive taxonomic and nomenclatural shuffling by Smith (1942 and 1951), Bogert and Oliver (1945), Milstead (1953), and Fitch and Milstead (1961). Smith recognized in Michoacán three members of the T. eques (= dorsalis) complex: eques eques, eques postremus, and vicinus. Later, Smith (1951) showed that the specific name eques had been misapplied, so that T. eques eques became T. cyrtopsis cyclides, and T. eques postremus became T. cyrtopsis postremus; under this arrangement T. vicinus stood unchanged. In the meantime, Bogert and Oliver (1945:359) presented a reinterpretation of Smith's data and suggested that T. vicinus, which differs from T. dorsalis cyclides only in lacking a middorsal stripe, "... is not a species, but only a pattern phase, possibly a simple mutant of T. e. eques" (= T. dorsalis cyclides, by present arrangement). Milstead (1953) agreed with Bogert and Oliver on the status of T. vicinus; furthermore, on the basis of only a few specimens, Milstead concluded that T. cyrtopsis postremus was not subspecifically distinct from T. cyrtopsis cyclides. Recently, Fitch and Milstead (1961) showed that Thamnophis dorsalis Baird and Girard (1853) was the correct name for the snakes that had been recognized as Thamnophis cyrtopsis Kennicott (1860). Consequently, the snakes referred to T. eques eques by Smith (1942) and to T. cyrtopsis cyclides by Smith (1951) and Milstead (1953) are now T. dorsalis cyclides.
Aside from one specimen from Temazcal and nine from Morelia (paratypes of T. vicinus), only two other specimens completely lacking the middorsal stripe have been seen; one is a male (UMMZ 102510) having 161 ventrals and an incomplete tail from Pino Gordo, and the other is a male (CNHM 39060) from Tancítaro having 158 ventrals and an incomplete tail. A female from Tancítaro (CNHM 39061) having 153 ventrals and 77 caudals has no lateral stripes and only a narrow middorsal stripe on the anterior part of the body. Throughout the region where T. vicinus-like snakes have been found, typical T. dorsalis cyclides occurs in much greater numbers. I concur with Bogert and Oliver in placing T. vicinus as a synonym of T. dorsalis cyclides.
Fig. 10. Dorsal color pattern of Thamnophis dorsalis cyclides (A) and Thamnophis dorsalis postremus (B).
Milstead (1953) had available few specimens of Thamnophis dorsalis from the Tepalcatepec Valley. The large series now in existence shows that the population in the Tepalcatepec Valley differs distinctly from that inhabiting the Mexican Plateau, Cordillera Volcánica, and Sierra de Coalcomán. Therefore the name T. dorsalis postremus Smith (1942) is resurrected for the population in the Tepalcatepec Valley. T. dorsalis cyclides and T. dorsalis postremus differ in color pattern (Fig. 10) and in scutellation (Table 6). Specimens from the Mexican Plateau and mountain ranges have a distinct light stripe on the second and third scale rows, a dark brown dorsum having squarish black spots, and a row of dark spots on the first row of dorsal scales. Specimens from the Tepalcatepec Valley have a grayish brown dorsum having smaller and less distinct dark spots and no light stripe on the second and third scale rows; the first, second, and third rows of scales are colored like the venter. In some specimens there are small dark flecks on the first row of dorsal scales.
Table 6.—Variation in Scutellation in Thamnophis dorsalis.
| Character | Mexican Plateau | Sierra de Coalcomán | Tepalcatepec Valley | |
| Ventrals | ♀ N | 31 | 2 | 32 |
| Mean | 164.0 | 156.5 | 144.6 | |
| Range | 153-171 | 154-159 | 138-151 | |
| ♂ N | 19 | 2 | 32 | |
| Mean | 153.5 | 154.7 | 138.3 | |
| Range | 149-159 | 149-159 | 131-141 | |
| Caudals | ♀ N | 28 | 2 | 29 |
| Mean | 83.8 | 81.0 | 73.4 | |
| Range | 80-100 | 79-83 | 70-79 | |
| ♂ N | 14 | 2 | 28 | |
| Mean | 78.0 | 72.0 | 68.5 | |
| Range | 71-87 | 72 | 63-73 | |
One specimen from Uruapan (1550 meters) and one from Coalcomán (950 meters) are intermediate in color pattern between T. dorsalis cyclides and T. dorsalis postremus. Both have indistinct lateral stripes and only small dark spots below the stripes. In scutellation these specimens are like T. dorsalis cyclides.
In Michoacán Thamnophis dorsalis cyclides has been collected in a variety of habitats on the Mexican Plateau: pine-oak forest, fir forest, marshes, and cleared land from 1550 to 2800 meters. In the Sierra de Coalcomán one was taken in broad-leafed forest at 950 meters, three in pine-oak forest at 2100 meters, and one in pine forest at 2300 meters.
Thamnophis dorsalis postremus Smith
Thamnophis eques postremus Smith, Zoologica, 27:109, October 23, 1942.—El Sabino, Michoacán, México.
Thamnophis cyrtopsis postremus Smith, Copeia, no. 2:140, June 8, 1951.
Thamnophis cyrtopsis cyclides (part), Milstead, Texas Jour. Sci., 5:368, September, 1953.
Thamnophis dorsalis postremus, Fitch and Milstead, Copeia, no. 1:112, March 17, 1961.
Apatzingán (31); Capirio (2); Charapendo; Cuatro Caminos (22); El Sabino; Lombardia (9); Nueva Italia (8); Uruapan (3).
The reasons for recognizing the population of Thamnophis dorsalis in the Tepalcatepec Valley as distinct from that on the surrounding highlands are presented in the discussion of Thamnophis dorsalis cyclides. In certain features of coloration and in the low numbers of ventrals and caudals, T. dorsalis postremus shows more resemblance to T. dorsalis sumichrasti than to T. dorsalis cyclides. According to Milstead (1953:367), T. dorsalis cyclides ranges southward from the Río Balsas in southwestern México. If specimens could be obtained from the upper Balsas Basin they might show that T. dorsalis postremus inhabits that extensive basin.
In the Tepalcatepec Valley T. dorsalis postremus is most frequently found at night in the rainy season, at which time the snakes are abundant near temporary pools where frogs are breeding. The absence of specimens from the coastal lowlands of Guerrero, Michoacán, and Colima indicate that, although the species inhabits the lowlands of the Tepalcatepec Valley, its range does not include the coastal lowlands.
A female (UMMZ 119402 from Cuatro Caminos) having 139 ventrals and a body length of 576 mm., on June 20, 1958, gave birth to 25 young, of which 18 (9 males and 9 females) were preserved. In body length the males varied from 132 to 141 (137.3) mm.; the females, 125 to 137 (133.1) mm. In tail length the males varied from 38 to 44 (42.4) mm.; females, 35 to 42 (39.7) mm. The males have 138 to 147 (142.2) ventrals and 70 to 75 (72.9) caudals; females have 131 to 140 (135.8) ventrals and 63 to 71 (67.0) caudals.
Thamnophis eques eques (Reuss)
Coluber eques Reuss, Zool. Misc., p. 152, 1834.—México. Type locality restricted to Guadalajara, Jalisco, México, by Smith and Taylor (1950a:334).
Thamnophis macrostemma macrostemma, Smith and Taylor, Bull. U. S. Natl. Mus., 187:163, October 5, 1945.
Thamnophis subcarinata subcarinata, Smith, Herpetologica, 5:63, May 31, 1949.
Thamnophis eques eques, Smith, Copeia, no. 2:139, June 8, 1951.
Jiquilpan; Lago de Cuitzeo; Lago de Pátzcuaro (17); Pátzcuaro (5); Tangancícuaro; Tupátaro (2); Undameo; Zacapu.
Although this snake has been collected in open pine-oak forest and in oak-bunch grass associations, it seems to reach its greatest abundance in marshes on the Mexican Plateau at elevations of 1550 to 2300 meters.
Thamnophis melanogaster canescens Smith
Thamnophis melanogaster canescens Smith, Zoologica, 27:117, October 23, 1942.—Chapala, Jalisco, México.
Lago de Cuitzeo (5); Lago de Pátzcuaro; Pátzcuaro; Tacícuaro; Tangamandapio (2).
This species of garter snake seems to be most abundant in the marshes adjacent to the lakes on the Mexican Plateau in Michoacán and Jalisco. At these elevations (1550 to 2200 meters) it often is found in association with Thamnophis eques eques and sometimes with Thamnophis dorsalis cyclides. On June 11, 1958, individuals of this species were found in a hyacinth-choked marsh at Tangamandapio at night.
One specimen from Tangamandapio (UMMZ 119414) had, in life, a dark chocolate brown dorsum, reddish brown sides, and cream-colored belly, chin, and labials. There were no longitudinal dorsal stripes.
Thamnophis scalaris scaliger (Jan)
Tropidonotus scaliger Jan, Elenco sistematico degli Ofidi, p. 70, 1863.—No type locality designated. Type locality restricted to Mexico City, Distrito Federal, by Smith and Taylor (1950a:329).
Thamnophis scalaris scaliger, Smith, Zoologica, 27:103, October 23, 1942.
Cerro Tancítaro (2); Nahuatzen; Opopeo; 26 km. S of Pátzcuaro.
The few specimens of this species from Michoacán have been collected at elevations from 1800 to 3400 meters in pine or fir forest in the Cordillera Volcánica.
Micrurus distans michoacanensis (Dugès)
Elaps diastema michoacanensis Dugès, La Naturaleza, ser. 2, 1:487, 1891.—Michoacán. Type locality restricted to Apatzingán, Michoacán, México, by Smith and Taylor (1950a:335).
Micrurus distans michoacanensis, Zweifel, Amer. Mus. Novitates, 1953:11, June 26, 1959.
Apatzingán (6).
All specimens were collected in the arid scrub forest of the Tepalcatepec Valley. The number of black rings on the body varies from six to eleven. In this respect they agree with the diagnosis of this subspecies presented by Zweifel (1959b:9).
Micrurus laticollaris (Peters)
Elaps marcgravii laticollaris Peters, Monats. Akad. Wiss. Berlin, p. 877, 1869.—Izúcar de Matamoros, Puebla, México.
Micrurus laticollaris, Schmidt, Publ. Field Mus. Nat. Hist., zool. ser., 20:39, December 11, 1933.
El Sabino (2); Lombardia.
This species ranges throughout the Balsas-Tepalcatepec Basin westward into Colima; specimens from Michoacán were collected in arid scrub forest at elevations from 500 to 1050 meters. The limited observations on Micrurus distans michoacanensis and M. laticollaris indicate that, at least in the Tepalcatepec Valley, M. laticollaris seems to inhabit slightly more mesic areas than does M. distans michoacanensis.
Pelamis platurus (Linnaeus)
Anguis platura Linnaeus, Systema naturae, ed. 12, 1:391, 1766.—Pine Island, Pacific Ocean.
Pelamis platurus, Gray, Ann. Philos., p. 15, 1825.
Boca de Apiza.
In November, 1955, Alfonzo Gonzales, a geographer from the University of Texas, observed sea snakes on the beaches of Michoacán. In May, 1956, Donald D. Brand of the University of Texas gave me one specimen of Pelamis platurus that he obtained on March 2, 1956, at Boca de Apiza. Furthermore, he supplied me with the following observations based on his field work along the coast of Michoacán from the Río Coahuayana to Maruata from March 1, to April 15, 1956. At that time many sea snakes were observed; in some places living and dead individuals were seen on the beaches; innumerable snakes were seen in the surf. When live individuals were taken from the beach and thrown into the ocean, they usually swam to shore. Many partially eaten individuals were seen protruding from crab holes. Inquiries among the natives resulted in the following information: Sea snakes are frequently seen between November and April, but most commonly in March and April, at which time the water is cold. The natives referred to the sea snakes as "culebra del mar." Most natives said that the snakes were not poisonous; others did not know of any venomous properties. In May, 1956, I worked the coastal region from the Río Coahuayana to La Placita and saw no sea snakes. In the summer of 1950 James A. Peters, and in the summer of 1951 I worked nearly the entire coastal region of Michoacán; during that time no Pelamis were seen. Insofar as I know, this is the first report of such seasonal activity in Pelamis platurus in the Americas.
Agkistrodon bilineatus bilineatus Günther
Ancisdrodon bilineatus Günther, Ann. Mag. Nat. Hist., ser. 3, 12:364, 1863.—Pacific coast of Guatemala.
Agkistrodon bilineatus bilineatus, Burger and Robertson, Univ. Kansas Sci. Bull., 34 (1):213, October 1, 1951.
Apatzingán; El Sabino; La Playa; Los Reyes.
All specimens from Michoacán are from inland localities between 300 and 1500 meters. The one from Los Reyes (USNM 46416) was collected by Nelson and Goldman on February 13, 1903. The elevation of Los Reyes (1500 meters) seems unusually high for this species, but otherwise there is no reason to doubt the authenticity of the record. Goldman (1951:192) in his description of Los Reyes stated: "Los Reyes is near the boundary between the Lower Austral and Arid Upper Tropical Zones but is preponderantly tropical in zonal character. The regular crops are mainly sugar cane, rice, and corn." Thus the biotic features of the area are not noticeably different from those at El Sabino and La Playa at lower elevations. The development of extensive agriculture through irrigation in the Tepalcatepec Valley and planting of rice and sugar-cane in that area may produce a more widespread habitat for this snake.
The absence of specimens from the coastal lowlands is due solely to inadequate collecting; the natives there know the snake and report that it is not uncommon in certain areas.
Crotalus basiliscus basiliscus (Cope)
Caudisonia basilisca Cope, Proc. Acad. Nat. Sci. Philadelphia, September 30, 1864.—Colima. Type locality restricted to Colima, Colima, México, by Smith and Taylor (1950a:328).
Crotalus basiliscus basiliscus, Gloyd, Nat. Hist. Misc., 17:1, April 23, 1948.
Apatzingán (4); Camachines; Coalcomán; El Ticuiz.
Specimens from southern Michoacán have fewer ventrals and caudals than do those from the northern part of the range; three males and three females have, respectively, 178, 182, 182, 185, 186, and 188 ventrals, and 27, 28, 29, 22, 29, and 29 caudals. Klauber (1952:81) gave the following data for Crotalus basiliscus (based on specimens from the entire range, except Oaxaca): ventrals in males, 179-201 (191.4), in females, 185-206 (197.6); caudals in males, 26-36 (30.7), in females, 21-29 (24.4). Klauber (1952:84) remarked that the one specimen that he had seen from Apatzingán had fewer ventrals and caudals than most other specimens. The low numbers of ventrals and caudals in specimens from Michoacán, as compared with more northern populations, may be indicative of a trend in the reduction of the numbers of these scutes from north to south. The southernmost examples of Crotalus basiliscus (Crotalus basiliscus oaxacus from Oaxaca) have 172-175 ventrals and 21 caudals (Gloyd, 1948).
In Michoacán Crotalus basiliscus basiliscus has been found in arid habitats on the coast, in the Tepalcatepec Valley, and in the lower parts of the Sierra de Coalcomán. All specimens are from localities below 1070 meters in elevation.
Crotalus durissus culminatus Klauber
Crotalus durissus culminatus Klauber, Bull. Zool. Soc. San Diego, 26:65, August 8, 1952.—El Sabino, Michoacán, México.
El Sabino (18).
These specimens are part of the type series and were collected by Hobart M. Smith near the upper limits of the arid scrub forest at an elevation of about 1050 meters on the lower slopes of the Cordillera Volcánica at the northern edge of the Tepalcatepec Valley. They were discussed in detail by Klauber (1952:66-70).
Crotalus intermedius intermedius Troschel
Crotalus intermedius Troschel, in von Müller, Reisen in Vereiningten Staaten, Canada und Mexico, vol. 3, p. 613, 1865.—Type locality unknown.
Crotalus intermedius intermedius, Klauber, Bull. Zool. Soc. San Diego, 26:9, August 8, 1952.
Cerro Tancítaro.
The one specimen is from the pine forests on the Cordillera Volcánica. At the present time this species is known from scattered localities in west-central Veracruz, Oaxaca, Michoacán, and as Crotalus intermedius omiltemanus in Central Guerrero. Apparently it is restricted to montane environments.
Crotalus molossus nigrescens Gloyd
Crotalus molossus nigrescens Gloyd, Occ. Pap. Mus. Zool. Univ. Michigan, 325:2, January 28, 1936.—Four miles west of La Colorada, Zacatecas, México.
Carapan; Los Conejos; Pátzcuaro; Tacícuaro (5).
In Michoacán this species has been found in pine forests between 1550 and 2300 meters in the Cordillera Volcánica. I expected to find it in the Sierra de Coalcomán, but inquiries among the natives living in the pine forests of that mountain range revealed that the people there have no knowledge of a large species of rattlesnake.
Crotalus polystictus (Cope)
Caudisonia polysticta Cope, Proc. Acad. Nat. Sci. Philadelphia, 17:191, December 26, 1865.—Tableland of México. Type locality restricted to Tupátaro, Guanajuata, México, by Smith and Taylor (1950a:330).
Crotalus polystictus Cope, in Yarrow, Wheeler's Rept. Geog. Geol. Expl. Surv. W. 100th. Mer., vol. 5, p. 533, 1875.
Tacícuaro (4); Tupátaro (2).
Formerly this species was abundant in the marshes around Lago de Chapala. The draining of these marshes probably resulted in reducing the numbers of these rattlesnakes. The species is known only from the Mexican Plateau at elevations of 1450 to 2400 meters.
Crotalus pusillus Klauber
Crotalus pusillus Klauber, Bull. Zool. Soc. San Diego, 26:34, August 8, 1952.—Tancítaro, Michoacán, México.
Acuaro de las Lleguas (2); Carapan; Cerro Tancítaro (16); Dos Aguas (12).
Aside from the type series of Crotalus pusillus from Cerro Tancítaro and one specimen from Carapan referred to the species by Klauber (1952:38), there are fourteen specimens from the Sierra de Coalcomán. These specimens (UMMZ 112566-7, 118591-9, 118601, 121512-3) are like Crotalus pusillus from Cerro Tancítaro in having the prefrontals paired, a black proximal rattle, and the underside of the tail black. The prefrontals are bordered posteriorly by one scale in two specimens, by two scales in three specimens, and by three scales in the other nine. The snakes from the Sierra de Coalcomán have 40 to 46 (42) dorsal body blotches. Ten males have 150-158 (154.4) ventrals and 29-33 (31.0) caudals; two females have 157 and 160 ventrals, and 25 and 27 caudals. The largest specimen is a male having a body length of 545 mm. and a tail length of 63 mm. The only noticeable difference between the specimens from the Sierra de Coalcomán and the topotypic series is that the latter have fewer dorsal blotches; the range of variation is 33 to 46 (39.8).
Most specimens of this species have a grayish brown dorsum and dark brown dorsal blotches. Two specimens from Dos Aguas (UMMZ 118596 and 118599) are pale brown above and have indistinct blotches.
One specimen from Dos Aguas regurgitated a large Gerrhonotus imbricatus imbricatus; of two others from the same locality, one regurgitated a Sceloporus bulleri and an Eptesicus fuscus. The latter specimen was collected at the entrance of a small cave, where it probably had captured the bat.
In the Cordillera Volcánica Crotalus pusillus has been obtained in pine-oak forest at elevations between 1550 and 1800 meters. In the Sierra de Coalcomán two specimens were taken in pine forest at an elevation of 2300 meters; ten other were found beneath rocks and logs in pine-oak forest at an elevation of 2100 meters.
Crotalus triseriatus aquilus Klauber
Crotalus triseriatus aquilus Klauber, Bull. Zool. Soc. San Diego, 26:24, August 8, 1952.—Alvarez, San Luis Potosí, México.
Morelia (10); Tacícuaro (2).
I am following Klauber (1952) in assigning some of the specimens of this species from Michoacán to the subspecies aquilus and others to C. t. triseriatus. The distinguishing characters of these subspecies are given by Klauber (1952:28). On the basis of the few localities from which the species is known in Michoacán it seems as though C. t. aquilus inhabits the open grassy areas on the Mexican Plateau and the associated open pine-oak or oak-bunch grass habitats to the north and east of the Cordillera Volcánica. Crotalus triseriatus aquilus has been collected at elevations from 1600 to 2000 meters in Michoacán.
Crotalus triseriatus triseriatus (Wagler)
Uropsophus triseriatus Wagler, Natürliches System der Amphibien, p. 176, 1830.—México. (Probably Mexico City.)
Crotalus triseriatus triseriatus, Klauber, Bull. Zool. Soc. San Diego, 26:19, August 8, 1952.
Cerro Tancítaro (36); Opopeo; Pátzcuaro.
This small rattlesnake inhabits rocky areas in pine and pine-oak forests above 1600 meters in the Cordillera Volcánica; it has been collected at 3270 meters on Cerro Tancítaro. The series reported by Schmidt and Shannon (1947:84) is a mixture of specimens of Crotalus triseriatus and Crotalus pusillus. The two species are found together on Cerro Tancítaro, but only Crotalus pusillus inhabits the coniferous forests of the Sierra de Coalcomán. Klauber (1952:30) stated that despite the proximity of Crotalus triseriatus triseriatus and Crotalus triseriatus aquilus in Michoacán, there is no evidence of intergradation. He went on to suggest that additional material might show that the two named populations actually are distinct species. The specimens that have been studied since Klauber's investigations also show no evidence of intergradation, but there still is no known sympatry of the populations.
The small montane rattlesnakes belonging to the species C. pricei, C. pusillus, and C. triseriatus present a problem in systematics and distribution worthy of intensive investigation. A knowledge of the distribution and relationships of the various populations of these snakes, together with other species also living in isolated populations on the higher mountains in México, probably will be of great significance in understanding dispersal and differentiation of animals during the Pleistocene.