Specimens examined.—Total number, 19, listed by localities from north to south and unless otherwise indicated in the United States National Museum.
Panamá: Boquete, 10 (3[75], 1[8], 1[2], 3[4], 1[7]); Río Gariche [é], 5300 ft., 1[1]; Siola, 1[1]; Chiriquí, 1[7]; Río Indio, near Gatún, 1; Mt. Pirre, 3 (2[1]); Calovebora, 1[7] (locality not found, possibly misspelling of Calovébora); no locality more definite than Panamá, 1[4].
Mustela frenata meridana Hollister
Long-tailed Weasel
Plates [25], [26], [27], [37], [38] and [39]
Mustela meridana Hollister, Proc. Biol. Soc. Washington, 28:143, July 10, 1914.
Putorius affinis, Robinson and Lyon, Proc. U. S. Nat. Mus., 24:147, October, 1901; Allen, Bull. Amer. Mus. Nat. Hist., 30:256, December 2, 1911.
Mustela affinis, Osgood, Field Mus. Nat. Hist. Publ. 155, zoöl. ser. 10:61, January 10, 1912.
Putorius macrurus, Allen, Bull. Amer. Mus. Nat. Hist., 31:92, April 19, 1912.
Mustela affinis affinis, Allen, Bull. Amer. Mus. Nat. Hist., 35:100, April 28, 1916 (part).
Mustela affinis costaricensis, Allen, Bull. Amer. Mus. Nat. Hist., 35:101, April 28, 1916 (part).
Mustela frenata meridana, Hall, Carnegie Instit. Washington Publ. 473:110, November 20, 1936; Hall, Physis, 16:175, 1939.
Type.—Male, subadult, skull and skin; no. 123341, U. S. Nat. Mus., 1630 meters elevation, Montes de Mérida, near Mérida, Venezuela; August 14, 1903; obtained by S. Briceno.
The skull (plates [25] and [26]) lacks the right exoccipital condyle and posterior half of the right zygomatic arch. The teeth all are present, unworn and entire. The skin is well made and complete.
Range.—Near sea level (San Julián) to 8500 feet (Montes de Culata, Mérida, Venezuela), and 9000 feet (Santa Elena, Colombia). Temperate to Subtropical life-zones of Venezuela and northern and western Colombia. See figure [29] on page [221].
Characters for ready recognition.—Differs from Mustela africana stolzmanni by absence of median, longitudinal, abdominal stripe of same color as upper parts, presence of p2 and two roots, rather than one root, on P2; from M. frenata panamensis in lighter color of upper parts (tone 3 rather than tone 4, pl. 344, Reddish Black, Oberthür and Dauthenay), flat rather than convex dorsal outline of skull immediately behind postorbital processes (see pl. 27); from M. f. affinis, in males, by lesser average breadth and length of skull and greater actual and relative size (see measurements) of facial part of skull; from M. f. aureoventris, in males, by lighter upper parts (tone 3 rather than tone 4, pl. 344, Reddish Black, Oberthür and Dauthenay) and by smaller skull and teeth (basilar length less than 45, length of m1 less than 6.3, width of M1 less than 4.8, outside length of P4 less than 5.7).
Description.—Size.—Male: Average and extreme measurements of topotypes (as recorded by collectors on labels, and so uniform as to show them not to be accurate to within more than 5 mm.) are as follows: Total length, 434 (410-460); length of tail, 164 (150-180); length of hind foot, 50 (no variation in collectors' measurements). Tail averages 61 per cent as long as head and body. Length of hind foot more than basal length. Corresponding measurements of no. 22191, a young male from Mérida, measured by Osgood or Conover, are 439, 165, 54. The adult male no. 18703, from Páramo de Tama (eastern boundary of Venezuela) has the following measurements written on the label by Osgood: 404, 150, 47.
Female: Average and extreme measurements of topotypes (as recorded by collectors on labels and so uniform as to show them not to be accurate to within more than 5 mm.) are as follows: Total length, 347 (320-370); length of tail, 128 (120-130); length of hind foot, 40 (no variation in collectors' measurements). Tail averages 57 per cent as long as head and body. Length of hind foot more than basal length. Two females, adult no. 11034 and young no. 11033 from Cincinnati, Santa Marta, Colombia, measured by M. A. Carriker, Jr., measure, respectively, as follows: 371, 330; 140, 140; 38, 36. No. 14463, adult, from Río Zapata, Colombia, measured (by J. H. Batty), 315, 138, 39. No. 32182, adult, from Mira Flores, Cauca, Colombia, measured (by W. B. Richardson), 375, 150, 43.
The average differences in external measurements of the two sexes, at Mérida, are: Total length, 87; length of tail, 36; length of hind foot, 10.
Externals.—Longest facial vibrissae black (few rarely white) and extending beyond ear; carpal vibrissae colored like underparts or upper parts, and not extending beyond apical pad of fifth digit; hairiness of foot soles slightly greater than shown in figure [21].
Color.—As described in Mustela frenata panamensis except that: Posterior fourth of each upper lip rarely, and small spot in front of ear usually, white; black of head proper not extending back of ears and grading insensibly into color of upper parts; anterior half of upper parts of adults "frosted" with numerous white hairs (tick bites?), upper parts near (n) Bay or tone 2 of Reddish Black (pl. 344, Oberthür and Dauthenay) or tone 3 in freshest, unfaded pelage. Least width of color of underparts (in ten males from Mérida) 20 (17-23) per cent of greatest width of color of upper parts. Black tip of tail, in same series, 60 to 75 mm. long, thus longer than hind foot and 41 (40-44) per cent as long as tail-vertebrae.
Skull and teeth.—Male (based on type specimen and seven topotypes, five adults and three subadults): See measurements and plates [25]-[27]; weight, 4.1 (3.8-4.3) grams; basilar length, 43.6 (42.3-44.3); zygomatic breadth more than distance between condylar foramen and M1 or than between anterior palatine foramen and anterior margin of tympanic bulla; mastoid breadth less than postpalatal length; postorbital breadth greater than length of upper premolars or than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; interorbital breadth not less than distance between foramen opticum and anterior margin of tympanic bulla; breadth of rostrum greater than length of tympanic bulla; least width of palate greater than length of P4; anterior margin of tympanic bulla as far posterior to foramen ovale as width of 4 to 5 upper incisors; height of tympanic bulla less than distance from its anterior margin to foramen ovale; length of tympanic bulla more or less than (approximately equal to) alveolar length of lower molar and premolar tooth-row and shorter than rostrum; anterior margin of masseteric fossa posterior to m2 and confined to posterior third (34 per cent average, 32 minimum, 37 maximum) of mandible.
Female (based on four adult topotypes): See measurements and plates [37]-[39]; weight (no. 143665), 2.3 grams; basilar length 37.2 (36.3-38.2); zygomatic breadth more or less than distance between condylar foramen and M1 or than distance between anterior palatine foramen and anterior margin of tympanic bulla; postorbital breadth (sinuses badly infested with parasites) more than length of upper premolars or width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; least width of palate more than length of P4; tympanic bulla as far posterior to foramen ovale as combined width of 4 to 5 upper incisors; height of tympanic bulla less than (one half to three fourths of) distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar and premolar tooth-row.
The skull of the female is 44 per cent lighter than that of the average male.
Comparisons of the skull with those of M. f. panamensis and affinis have been made in the accounts of those subspecies. As compared with the skull of the male of M. f. aureoventris, that of meridana averages smaller in every measurement taken. Indeed, none of the skulls of meridana equals that of aureoventris in basilar length, length of tooth-rows, length of tympanic bulla, depth of skull at anterior margin of basioccipital or at posterior margin of upper molars, or measurements of teeth. Relative to the basilar length, most of the measurements are greater in meridana. Exceptions are the relative length of the tooth-rows, and the two measurements of depth of the skull which average less.
Remarks.—In 1914 when Hollister named this weasel he compared it with M. f. affinis and most of the differential characters which he ascribed to meridana were merely "more than" or "less than" in affinis. In affinis, Hollister included specimens from Chiriquí, Panamá, and the coast of Venezuela. The specimens from these three places were referred by Allen (1916:101) to Mustela affinis costaricensis, and he restricted (op. cit.:100) the type locality of Mustela affinis affinis to Bogotá, Colombia, and synonymized Mustela meridana with M. a. affinis. Hollister probably would not have named meridana had he had specimens from Bogotá for comparison and had he regarded them as topotypes of affinis for the difference is slight. Nevertheless, within the large geographic range of M. f. meridana there is some geographic variation. There is more of such variation in the color of the pelage than in shape and size of the skull. The specimen from San Julián is darker than the average and in this respect approaches true panamensis. San Julián is situated at a relatively low elevation on the coast of Venezuela.