Spotted Tolucan Earthsnake

description

Description: A species with divided prefrontals and internasals; loreal scale on each side of head; a pointed rostral; nasal pierced by nostril on each side of head; a preocular and two postoculars; hexagonal frontal, contacting prefrontals; temporal formula 1 + 2; 7 upper and lower labials; 2.5 upper labials before eye; genial shields separated by one scale; a mean of 123 ventrals (106 – 135) and 31 subcaudals (28 – 42); 17 rows of smooth scales at midbody; dorsum brown, with vertebral line of elongated hexagonal spots; sides of body tessellated; venter yellowish, with no marks. Measurements: Adult specimens of Conopsis acuta average 185.4 mm snout­vent length (120 – 225 mm), 222.0 mm in total length (153 – 270 mm), body diameter 7.2 mm. Variation: This species generally shows a loreal scale on each side of head (68.8 % of examined specimens), or loreal may be missing in some (31.2 %). Upper labials usually 7 – 7 (86.2 %), but some have 6 – 6 (10.4 %); or 7 – 6 (3.4 %). Upper labials before eye from 2.5 (69 %) to 3 (31 %). Lower labials from 7 (65.6 %) to 6 (31.1 %), one specimen had 5 – 7. First pair of genial shields separated by one (75.9 %) or two scales (13.8 %), or may be fu

Taxonomic summary of Conopsis, Günther, 1858 (Serpentes: Colubridae)

description

We propose to restrict the type locality for Conopsis acuta to: 2 millas E Ixtlán de Juárez (AMNH 91054), since apparently Cope, 1886 made a mistake citing the locality for the specimen he described as from " .... Tuchitan, on the Pacific side of the isthmus of Tehuatepec. ". Latter Smith and Taylor (1950: p. 338) pointed that the type locality for this taxon is Juchitán, Oaxaca. The type specimen was sent to the US National Museum by Sumichrast (Cope, 1886 in Ferrari­Perez: 189). Our restriction is based on the statement of Sumichrast (1873) refering the species as inhabiting the temperate highlands of Mexico. This locality may have been within the sphere of Sumichrast activity and was probably readily accessible to him.

Taxonomic summary of Conopsis, Günther, 1858 (Serpentes: Colubridae)

diagnosis

Diagnosis: This snake is characterized by the following combination of characters: divided internasals and prefrontals; brown dorsal coloration, or some individuals with a grayish dorsum and a vertebral line of elongated hexagonal spots; with tessellated sides, or two paravertebral dark lines. Ventrally it is yellowish or yellow­orange, with no spots or with a row of paired dots on each end of the ventral scales. It differs from C. nasus and C. megalodon by having divided prefrontals and internasals, scales fused in the latter two species. The dorsal spot pattern may be similar in the three. Conopsis acuta is a smaller snake (SVL 100 – 225 mm) compared to the other two species, C. nasus (SVL: 100 – 320 mm) and C. megalodon (SVL: 107 – 250 mm); C. acuta differs from C. lineata by lacking continuous lines along the dorsum and its smaller size (C. lineata SVL: 100 – 273 mm).

Taxonomic summary of Conopsis, Günther, 1858 (Serpentes: Colubridae)

distribution

Distribution: Conopsis acuta is distributed in the highlands of south­central Mexico (fig. 2); it has been collected in the states of Oaxaca, Puebla, and Veracruz, from 1800 to 2600 m, in xerophilous underbrush, Opuntia (prickly pear), pine, pine­oak, and fir forests. It is usually under rocks or litter during most of the year, being more abundant in the months of August, September, and November.

Taxonomic summary of Conopsis, Günther, 1858 (Serpentes: Colubridae)