ZGAP Ground Snake

description

Description of holotype. Adult female, SVL 376 mm, tail length 37 mm (9.8 % SVL); body diameter 9.1 mm; head length 11.7 mm (3.1 % SVL); head width 6.4 mm (1.7 % SVL); interocular distance 4.3 mm; head slightly distinct from body; snout-orbit distance 3.8 mm; rostral 2.5 mm wide, ca. as broad as high; internasals 1.3 mm wide; prefrontals 2.5 mm wide; frontal 3.1 mm wide, with a curvilinear triangular shape in dorsal view; parietals 2.4 mm wide (56 % length); nasal divided; loreal 1.6 mm long, ~ 2 x longer than high; eye diameter 1.7 mm; pupil round; supraoculars 1.2 mm wide; two postoculars; temporals 1 + 2; seven supralabials, third and fourth contacting orbit; symphysial 1.7 mm wide, ~ 2 x as broad as long, separated from chinshields by first pair of infralabials; seven infralabials, first three contacting chin shields; chinshields ~ 2 x as long as broad, posterior chinshields absent; dorsal scales arranged in 17 / 17 / 17 rows, smooth without apical pits; two preventrals; ventrals 173; anal plate single; 25 paired subcaudals.

Leaving no stone unturned: three additional new species of Atractus ground snakes (Serpentes, Colubridae) from Ecuador discovered using a biogeographical approach

description

Figs 5 g, 6, 7 Proposed standard English name: ZGAP Ground Snake. Proposed standard Spanish name: Culebra tierrera de ZGAP.

Leaving no stone unturned: three additional new species of Atractus ground snakes (Serpentes, Colubridae) from Ecuador discovered using a biogeographical approach

diagnosis

Diagnosis. Atractus zgap sp. nov. is placed in the genus Atractus, as diagnosed by Savage (1960), based on phylogenetic evidence (Fig. 1). The species is diagnosed based on the following combination of characters: (1) 17 / 17 / 17 smooth dorsals; (2) two postoculars; (3) loreal 2 x longer than high; (4) temporals 1 + 2; (5) seven supralabials, third and fourth contacting orbit; (6) seven infralabials, first three contacting chinshields; (7) seven maxillary teeth; (8) three rows of gular scales; (9) two or three preventrals; (10) 173 - 177 ventrals in females; (11) 31 subcaudals in an uncollected male and 25 - 27 subcaudals in females; (12) dorsal ground color brown with faint dark longitudinal lines (Figs 5 g, 6 a); (13) venter yellow with fine brown stippling (Fig. 6 b); (14) 376 mm SVL in the female holotype; (15) 37 mm TL in the female holotype.

Leaving no stone unturned: three additional new species of Atractus ground snakes (Serpentes, Colubridae) from Ecuador discovered using a biogeographical approach

distribution

Distribution. Atractus zgap sp. nov. is known only from five localities (See Suppl. material 1: Table S 1) along the valley of the Rio Quijos, Napo province, in the Amazonian slopes of the Andes in northeastern Ecuador, at elevations 1460 - 1703 m a. s. l. (Fig. 2).

Leaving no stone unturned: three additional new species of Atractus ground snakes (Serpentes, Colubridae) from Ecuador discovered using a biogeographical approach