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.