Redbelly Earth Runner

description

Description. Small, slender snake; head moderately wider than the neck. Adults reach 300 – 349 mm in total length, largest known male 319 mm, and the largest female 349 mm. Tail comprises 21 – 23 % of total length in males, 17 – 21 % in females. Prefrontals fused into a single, large scale, supraoculars are not fused with the postoculars, frontal relatively broad, and the nasal divided. Small internasals 1 / 1, loreals 1 / 1 that extend from the postnasal to anterior edge of eye (no preoculars), discrete postoculars 1 / 1; temporals 0 + 1, supralabials 5 – 6 with 3 – 4 entering orbit, infralabials 6 – 7 with 1 – 5 contacting anterior chinshields (fifth pair narrowly and first pair in contact along midline behind mental). Mental broader than long, anterior chinshields large, pair of posterior chingshields about one-fourth to one-third size of anterior pair. Keeled dorsal scale rows 15 - 15 - 15, preventrals 2 – 3, ventrals 123 – 127 in males and 126 – 130 ventrals in females. Cloacal scute undivided. Divided subcaudals 41 – 45 in males and 37 – 41 in females. Dorsal scale rows at midlength of tail 6. Pupil is subcircular to vertically oval. A conspicuous cream, yellow, or peach coll

Taxonomic review of the rare Mexican snake genus Chersodromus (Serpentes: Dipsadidae), with the description of two new species

description

Schmidtophis rubriventris Taylor, 1949, Univ. Kansas Sci. Bull. 33: 169 – 215 [193 – 194]. Holotype: LSUMZ 577. Type locality: “ near Xilitla (Xilitla Region), San Luis Potosí, Mexico. ”

Taxonomic review of the rare Mexican snake genus Chersodromus (Serpentes: Dipsadidae), with the description of two new species

diagnosis

Diagnosis. Chersodromus rubiventris can be distinguished from all Mexican species of snakes by having combination of prefrontals fused into single scale; postocular discrete from supraocular; anterior temporal absent; dorsal scales keeled in 15 rows at midbody, unreduced posteriorly; supralabials usually 6, third and fourth entering orbit; infralabials 7 – 8, usually 1 – 5 contacting anterior chinshields (5 narrowly); mental not contacting anterior chinshields; venter bright red. This species is easily differentiated from all species of Chersodromus by having 15 scales around body, mental scale in contact with anterior chinshields and anterior temporal absent (Table 1).

Taxonomic review of the rare Mexican snake genus Chersodromus (Serpentes: Dipsadidae), with the description of two new species

distribution

Distribution and habitat. This species is found in the Sierra Madre Oriental in the States of San Luis Potosí, Querétaro and Hidalgo (Fig. 1). Chersodromus rubriventris inhabits cloud forest between 700 – 1650 m asl, a habitat that has been fragmented in recent years (Ramírez-Bautista et al. 2013, Fig. 5 B).

Taxonomic review of the rare Mexican snake genus Chersodromus (Serpentes: Dipsadidae), with the description of two new species