Oswaldo Báez’ Snail-Eater

description

Description of holotype. Adult female, SVL 277 mm, tail length 85 mm (31 % SVL); head length 9.5 mm (3.4 % SVL) from tip of snout to commissure of mouth; head width 7.3 mm (76 % head length) taken at broadest point; snout-orbit distance 3.3 mm; head distinct from neck; snout short, blunt in dorsal and lateral outline; rostral 2.1 mm wide, broader than high; internasals 1.2 mm wide, broader than long; prefrontals 2.2 mm wide, slightly broader than long and contacting orbit; supraocular 2.6 mm long, longer than broad; frontal 2.9 mm long, pentagonal, in contact with prefrontals, supraoculars, and parietals; parietals 4.2 mm long, longer than broad; nasal not divided, in contact with first supralabial, loreal, prefrontal, internasal, and rostral; loreal 1.3 mm long, longer than high, entering orbit; eye diameter 2.2 mm; pupil semi-elliptical; no preocular; two postoculars; temporals 2 + 2; 6 supralabials, 3 rd and 4 th contacting orbit; symphysial separated from chinshields by the first pair of infralabials; 9 / 8 (right / left) infralabials, 1 - 6 / 1 - 5 contacting chinshields; both pairs of chinshields longer than broad; dorsal scales in 15 / 15 / 15 rows, smooth, without apical pi

Systematics of South American snail-eating snakes (Serpentes, Dipsadini), with the description of five new species from Ecuador and Peru

diagnosis

Diagnosis. Dipsas oswaldobaezi is placed in the genus Dipsas based on phylogenetic evidence (Fig. 3) and the absence of a labial that is noticeably higher than other labials and in contact with the postocular, primary and secondary temporals. The species differs from all described species of Dipsas based on the following combination of characters: (1) 15 / 15 / 15 smooth dorsals with a slightly enlarged vertebral row (1 - 1.2 times as wide as adjacent rows); (2) loreal and prefrontal in contact with orbit; (3) six supralabials with 3 rd and 4 th contacting orbit; (4) no infralabials in contact behind symphysial; (5) 163 - 179 ventrals in males, 177 - 179 in females; (6) 68 - 70 divided subcaudals in males, 65 - 66 in females; (7) dorsal ground color light sandy brown with a pattern of 55 - 63 drab to brown black-edged middorsal blotches that are wider (7 - 9 vertebral scale rows) and solid down to the edges of the ventrals on the first one third of the body, but becoming narrower (1 - 3 vertebral scales long) and broken up laterally towards the tail; interspaces finely speckled with brown pigment; ground color of the head light sandy brown with a thin light cream nuchal collar and

Systematics of South American snail-eating snakes (Serpentes, Dipsadini), with the description of five new species from Ecuador and Peru

distribution

Distribution. Deciduous and semideciduous lowland to lower montane forests and dry lowland shrublands in southwestern Ecuador (provinces of Loja and El Oro) and northwestern Peru (department of Tumbes), at elevation between 39 and 1289 m (Fig. 5).

Systematics of South American snail-eating snakes (Serpentes, Dipsadini), with the description of five new species from Ecuador and Peru

etymology

Etymology. The specific name oswaldobaezi honors Dr. Oswaldo Baez, a renowned Ecuadorian biologist and researcher who has dedicated his life to the teaching of science, scientific thinking, and the conservation of nature. Oswaldo Baez has played a major role in science education in Ecuador through many popular science articles and books.

Systematics of South American snail-eating snakes (Serpentes, Dipsadini), with the description of five new species from Ecuador and Peru