Apostolepis gaigeae, Savage, 1955

Passos, Paulo, Prudente, Ana L. C., Ramos, Luciana O., Caicedo-Portilla, José Rances & Lynch, John D., 2018, Species delimitations in the Atractus collaris complex (Serpentes: Dipsadidae), Zootaxa 4392 (3), pp. 491-520: 503-506

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Apostolepis gaigeae


Atractus gaigeae Savage, 1955  

Figures 3D View FIGURE 3 , 7 View FIGURE 7

Rhabdosoma maculatum   BOCOURTI 1883: 540. [ ZMB LECTOTYPE FROM ECUADOR; SEE SAVAGE (1955, 1960)] (IN PART). Atractus bocourti— BOULENGER 1896:645 (IN PART).

Atractus gaigeae SAVAGE, 1955   :12.

Atractus collaris   gaigeae   —DIxON & SOINI 1977:34.

Atractus gaigeae   — LEHR 2002:204 [ INDIRECTLY, BY RESTORING THE SPECIFIC RANK FOR THE FORMER SPECIES, Atractus collaris   ].

Holotype. Adult male ( UMMZ 82887 View Materials ) collected by Clarence Altenberg and Bancroft G. Buttler on 1935 without a precise location in the province of Zamora-Chinchipe (formerly Santiago-Zamora ), Ecuador. The specimen has a midventral incision exposing some viscera ( Fig. 7 View FIGURE 7 ).  

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 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).

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.

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   ).

Description. Head slightly distinct from body, twice as long as wide, and arched in lateral view; snout rounded in dorsal view and truncated in lateral view; rostrum-orbit distance about half of head length; nostril-orbit distance equivalent to pre-frontal length; interorbital distance equivalent to parietal length; rostral subpyramidal in frontal view, wider than high, and visible in dorsal view; internasals slightly wider than long; internasal suture sinistral with respect to prefrontal suture; prefrontal as wide as long; supraocular subtrapezoidal in dorsal view, about two times as long as wide; frontal subpyramidal, as long as wide; parietal about twice as long as wide; nasal divided; nostril between prenasal and postnasal; prenasal about twice as high as long; postnasal shorter than prenasal, as high as long; loreal long, contacting first three supralabials; pupil round; usually one postocular (73% on both sides and 91% only on one side) in females (n = 22 sides) and two postoculars (<80%) similar in height in males (n = 38 sides); upper postocular slightly longer than lower postocular; temporals 1+2; first temporal about two times as long as high; upper posterior temporals usually fused in a single shield, about five times as long as wide; supralabials seven, third and fourth contacting eye; first four supralabials similar in height; sixth supralabial taller and seventh supralabial longer than remaining supralabials; symphysial subtriangular, about three times as wide as long; fist pair of infralabials preventing symphysial/chinshields contact; infralabials seven, first three contacting chinshields; chinshields three times longer than wide; gular scales in four series; preventrals usually four; dorsal scale rows 17/17/17; dorsal scales usually with one apical pit (rarely two) on both sexes and supracloacal tubercles in mature males; terminal spine large (longer than last subcaudal), robust and slightly acuminate.

Maxilla arched in dorsal view with five or four prediastemal teeth and one postdiastemal tooth; first two teeth moderately spaced (smaller than teeth size); spaces among each one of third and fourth teeth longer (similar to the teeth size); prediastemal teeth, posteriorly curved, angular, robust at base and narrowed in the apices; teeth decreasing posteriorly in size; diastema longer than size of postdiastemal tooth; postdiastemal tooth half-sized of predistemal ones; lateral maxillary process little developed, lacking posterior projection.

Color pattern variation in preservative. Dorsum of head dark brown, usually with darker pigments restricted to the suture of cephalic shields and snout region, rostral, internasals and anterior prefrontals cream colored; cream spots or irregular blotches restricted to the center of each scale/shield or covering mostly of snout dorsally; posterior region of head with an incomplete conspicuous cream collar (two scales long); light collar extends from occipital region to lateroposterior end of parietals; parietals mostly dark borwn, precluding contact between each branch of the incomplete cream collar; lateral surface of head dark brown to dorsal edge of supralabials; supralabials mostly cream, except for posterior region of third and anterior region of fourth and anterior portion of sixth and seventh supralabials almost entirely dark brown; occasionally, suture between each supralabial scale dark brown with its central portion cream; temporal and occipital regions covered by cream collar, decreasing in length towards parietals; symphysial and infralabials with cream ground color sometimes covered with dark brown spots concentrated on the posterior regions of infralabials and anterior portion of chinshields; symphysial and infralabials rarely almost entirely brown pigmented; chinshields and gular region uniformly cream or with a few dark brown dots; ventral surface of body cream with conspicuous black spots on the lateral margins of ventral and subcaudal scales; black spots forming a conspicuous longitudinal stripe on the paraventral region of body; dorsum of body with dark brown to black band on neck (usually three scales long) forming an inverted “V” shaped collar; more rarely, dark collar discontinuous with each branch separate above vertebral region; dorsal ground color brown with a black vertebral line (one scale wide), paired black paravertebral spots (one or two scales long and wide), and dorsolateral stripes; paired spots located between sixth and seventh scales rows and dorsolateral stripes (one scale wide) covering second scale rows and, eventually, above ventral portion of third scale row between both series of scales; paraventral line originating from lateral margins of ventral scales usually extending dorsally to ventral edge of first scale row (half-scale wide); first scale row usually lighter (pale brown), contrasting among both dark lateral stripes.

Color pattern variation in life. Dorsum of head dark brown with cream to creamish red spots covering snout region; eye with brown to black iris; center of supralabials and infralabials cream; belly cream colored, except for black pigmented lateral margins of ventral scales; ventral surface of tail cream with dispersed black dots or spots, sometimes concentrated on the scales sutures; dorsal background of body brown, with black spots and stripes; paravertebral spots not bordered by light pigments; light dorsolateral stripes beige ( Fig 3D View FIGURE 3 ).

Microdematoglyphics. Scales of Atractus gaigeae   presents cell borders at midapical portion closer to each other (rarely exceeding 2.5 µm of distance) and more conspicuous pores at cell surface compared to A. collaris   ( Fig. 9B View FIGURE 9 ).

Hemipenis morphology. Retracted organ extends at level of eighth to ninth subcaudal and bifurcates at level of seventh to eighth subcaudal (n = 3). Fully everted and almost maximally expanded hemipenis (n = 1, USNM 217627) renders a moderately bilobed, non-capitate and non-calyculate; lobes centrolinearly oriented distally and slightly distinct from hemipenial body; distal portion of lobes clavate with nearly rounded apices; lobular region do not distinct from the hemipenial body (similar ornamentation and capitular groove absent); lobes and hemipenial body uniformly covered by alary spines (sensu Passos et al. 2013d); alary spines increasing in size below lobular region, forming irregular barely defined flounces at distal portion of hemipenial body on the asulcate side; alary spines irregular on the intrasulcar region and at medial portion of hemipenial body; sulcus spermaticus centrolinear, bifurcating at half length of organ and extending to lobe apices; sulcus spermaticus wide laterally expanded along all its extension; margins lacking spinules along almost all its extension; basal naked pocket indistinct; basal region of hemipenis with longitudinal plicae and small spinules irregularly distributed ( Figs. 10B View FIGURE 10 ).

Meristic and morphometric variation. Largest male 266 mm SVL, 34 mm CL; largest female 295 mm SVL, 21 mm CL; tail 11.7–15.9% SVL(mean = 14.0; SD = 1.3; n = 15) in males, 7.1–12.5% SVL (mean = 9.0; SD = 1.5; n = 10) in females; ventrals 184–198 (mean = 189.3; SD = 3.7; n = 18) in males, 200–214 (mean = 204.8; SD = 4.5; n = 10) in females; subcaudals in males 33–40 (mean = 36.1; SD = 1.7; n = 4), 23–28 (mean = 25.8; SD = 1.4; n = 10) in females; gular scale rows 3 (n = 3 sides) or 4 (n = 56 sides); postocular 1 (n = 7 sides) or 2 (n = 39 sides) in males, 1 (n = 14 sides) or 2 (n = 6 sides) in females; dorsal scale rows at level of second subcaudal 8–10 (x = 8.9; SD = 0.5; n = 58 sides); midbody diameter 2.0– 5.7 mm (mean = 3.6; SD = 0.8; n = 25); maxillary teeth 5 (n = 26 sides), 6 (n = 26 sides) or 7 (n = 2).

Distribution. From Cuyabeno (ca., 0 0 ° 25’27’’S, 76 ° 06’09’’W), province of Subumbíos, southeast to Chichirota (0232’S, 7638’W), and southwest to Taisha (02 ° 09’53’’S, 77 ° 39’32’’W) provence of Morona Santiago, along the Amazonian versant of Ecuador. Atractus gaigeae   occurs between 200–750 m asl ( Fig. 12 View FIGURE 12 ).


Museum f�r Naturkunde Berlin (Zoological Collections)


Forssa Museum of Natural History


American Museum of Natural History


California Academy of Sciences, Stanford University Collection


Escuela Polytecnica Nacional


Smithsonian Institution, National Museum of Natural History