Atractus gaigeae (SAVAGE, 1955)
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Higher Taxa | Colubridae (Dipsadinae), Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes) |
Subspecies | |
Common Names | E: Gaige's Ground Snake |
Synonym | Rhabdosoma maculatum BOCOURT 1883: 540 (in part) Atractus bocourti — BOULENGER 1896: 645 (in part) Atractus gaigeae SAVAGE 1955 Atractus gaigeae — PETERS & OREJAS-MIRANDA 1970: 29 Atractus collaris gaigeae — DIXON & SOINI 1977: 34 Atractus gaigeae — CARILLO & ICOCHEA 1995 Atractus gaigeae — PASSOS et al. 2007 Atractus gaigeae — WALLACH et al. 2014: 73 |
Distribution | Ecuador (Amazonas) Type locality: Santiago-Zaruma or Morona-Chinchipe Provinces, Ecuador. |
Reproduction | oviparous |
Types | Holotype: UMMZ 82887, adult male, collected by Clarence Altenberg and Bancroft G. Buttler on 1935 without a precise location in the province of Zamora-Chinchipe (formerly Santiago-Zamora), Ecuador. Paratypes: All specimens from the provinces of Napo and Pastaza, Ecuador: male (AMNH 35891) from a locality between Baños (01°25’S, 78°33’W) and Canelos; female (CAS-SU 15619) and male (CAS-SU 15620) from Canelos (01°35’S, 77°45’W; ca. 490 m); male (CAS-SU 15621) from headwaters of Bobonaza River (01°28’S, 53°40’W; ca. 250 m); male MEPN (also as EPN) 8693 (formerly EPN 48) from Bobonaza River, Sarayacu (01°44’S, 77°29’W; ca. 400 m); and EPN female 5272 (formerly EPN 46) from Bobonaza River, Chichirota (02°32’S; 76°39’W; ca. 250 m). Lectotype: ZMB [Rhabdosoma maculatum] |
Diagnosis | DIAGNOSIS: A form most closely resembling A. collaris of Ecuador and Perú and, to a lesser extent, ecuadorensis, occidentalis, and dunni. Distinct from these forms and all other Ecuadorian Atractus in: (1) 17 scale rows; (2) loreal long; (3) teeth on maxillary five or six; (4) ventrals in males, 187-198 (191); in females, 207-213 (210); and (5) pattern of seven dark stripes and two rows of regularly arranged dark spots [from SAVAGE 1960]. Diagnosis. Atractus gaigeae is distinguished from all congeners, except for those species of the A. collaris species group (see below the distinction among these members), by having one (usually) or two (rarely) apical pits on dorsal scales of both sexes and supracloacal tubercles on cloacal region of mature males (Passos et al. 2013b). Additionally, the following combination of morphological characters is unique from the species and also distinguishes it from any other species of Atractus: (1) dorsal scale rows 17/17/17 with apical pits on both sexes and supracloacal tubercles in mature males; (2) postoculars usually one in female and two in males; (3) loreal moderately long, contacting first three supralabials (4) temporals 1+2; (5) seven supralabials, third and fourth contacting eye; (6) infralabials six or seven, first three contacting chinshield; (7) maxillary teeth usually five or six; (8) gular scale rows usually four; (9) preventrals four; (10) ventrals 200–214 in females, 184–198 in males; (11) subcaudals 23–28 in females, 33–40 in males; (12) dorsum of head dark brown with an incomplete occipital light collar, dorsal ground color of body brown with paired paravertebral black spots and longitudinal stripes (rarely with vertebral but usually with dorsolateral lines); (13) belly almost immaculate cream, except for lateral edges of ventral scales dark brown forming paraventral lines; (14) small body size, females reaching 295 mm SVL, males 266 mm SVL; (15) small tail length in females (7.1–12.5% SVL), moderately long in males (11.7–15.9% SVL); (16) hemipenis moderately bilobed, non-capitate and non-calyculated (Passos et al. 2018). Comparisons. Atractus gaigeae differs from all members of the A. collaris species group, except for A. alphonsenhogei and A. collaris, in having first supralabial contacting loreal (vs. first supralabial not contacting loreal in A. caxiuana, A. hoogmoedi, A. surucucu, and A. zidoki). A. gaigeae differs from both species in having 200–214 ventrals in females, 184–198 in males (vs. 163–176 in females, 150–162 in males of A. alphonsehogei; and 167–186 in females, 145–178 in males of A. collaris) (Passos et al. 2018). |
Comment | Synonymy: fide Passos et al. 2018. Has been synonymized with A. collaris by DIXON & SOINI 1986. Dixon & Soini (1977) pointed out that the material they studied from Santa Maria (from Iquitos region of Peru) was “intermediary between A. collaris and A. gaigeae” and considered the latter taxon a subspecies of the former species. Distribution: see map in Passos et al. 2018: 513 (Fig. 12). Has been erroneously reported from Peru by Carrillo & Icochea (1995) and Pitman et al. (2011) in their lists of reptiles from Peru. |
Etymology | Named after Helen Beulah Thompson Gaige (1890-1976), American herpetologist at the University of Michigan. See Bell et al. 2021 for biographical data. |
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