Gonatodes superciliaris, Barrio-Amorós & Brewer-Carías, 2010

Barrio-Amorós, César L. & Brewer-Carías, Charles, 2010, Venezuelan Guayana, with the description of five new species, Zootaxa 1942, pp. 1-68 : 41-45

Gonatodes superciliaris sp. nov.

( Fig. 15A, B, C )

Sarisariñama Forest Gecko, Tuteque de Sarisariñama, Tamene-mü

Holotype. EBRG 4243 , an adult male from Sima Mayor , Sarisariñama-tepui, Estado Bolívar, Venezuela (4°41'77’’ N, 64°13'190’’ W), elevation 1100 m, collected by César L. Barrio-Amorós and Charles Brewer- Carías on 15 March 2002.

Paratypes. EBRG 4244 (an adult male) , EBRG 4245–46 (adult females) , EBRG 4247 (subadult female) , EBRG 4248 and EBRG 4369 (juveniles); all with same data as the holotype .

Referred specimens. EBRG 4166 , an adult female from NE sector of Sarisariñama, but without exact locality data, collected by Omar Linares on 27 November 1987. A lot of three eggs ( EBRG 4370 ) with same data as the holotype, collected by C. L. Barrio-Amorós.

Etymology. The specific name refers to the spine-like supraciliary scale, a diagnostic character of the species. It is a Latin adjective derived from super - (over or above) + cilium (eyelid) + - aris (an adjectival suffix meaning “pertaining to”).

Diagnosis. A Gonatodes with proximal subdigital lamellae narrower than digits; 22–28 lamellae under fourth toe; three lateral rows of scales on distal parts of fingers and toes; ventral surface of tail with repetitive series of single midventral scale in contact posterolaterally on each side with one scale followed by larger midventral scale in contact on each side with two scales (Type C of Rivero-Blanco 1979); elongate supraciliary spine present in both sexes; scales around midbody 80–96; ventrals in a longitudinal midventral row 35– 43. In life, males with a blackish-blue dorsal ground color; lower side of head and chest orange or yellow; females dark green with blue vertebral stripe, and two dorsolateral rows of yellow round spots that coincide with enlarged, spinelike scales.

Gonatodes superciliaris is easily distinguished from other Gonatodes in the Guiana Shield and Amazonia by the following characters (those of G. superciliaris in parentheses). Gonatodes annularis has a Type A (Type C) subcaudal scale pattern, that is two single midventrals followed by a divided midventral, three or four lateral rows of scales on distal parts of fingers and toes (three), 41–49 (35–43) ventrals, males with or without vivid yellow spots (never with spots) a blue iris (brown), and no elongate supraciliary spines (present). Gonatodes eladioi is smaller, up to 34 mm SVL (up to 49 mm SVL), has 14–16 (22–28) subdigital lamellae under the fourth toe, has two lateral rows of scales on distal parts of fingers and toes (three), 43–48 (35–43) ventrals, males have a vertebral stripe (no stripe), and it is distributed south of the Río Amazonas (Guiana Shield). Gonatodes hasemani is the most similar species by having an elongate supraciliary spine and spinelike scales in the round spots on the flanks, but it differs by having Type F (Type C) subcaudal pattern, that is no distinct midventral series of scales, 41–55 (35–43) ventrals, and males have white spots (males without spots). Furthermore, G. hasemani occurs south of the Río Amazonas, and the closest record is 1200 km south of Sarisariñama (Avila-Pires 1995). Gonatodes humeralis is widespread in South America east of the

Andes. It is a small species, up to 41.5 mm SVL (up to 49 mm SVL), with 15–21 (22–28) subdigital lamellae under the fourth toe, Type B (Type C) subcaudal pattern, two single midventrals followed by an enlarged one, 100–137 (80–96) scales around midbody, 48–78 (35–43) ventrals, and the dorsum in males with a red, yellow, and brown vermiculated pattern (males blackish-blue without vermiculations). Gonatodes tapajonicus has 18–23 (22–28) subdigital lamellae under fourth toe, Type A (like G. annularis ) and B (like G. humeralis ) subcaudal patterns (Type C), 116–126 (80–96) scales around midbody, 54–60 (35–43) ventrals, and the dorsum in males with vivid yellow and brown reticulation (males blackish blue).

Gonatodes superciliaris is unique among its congeners by having the following combination of characters: elongate supraciliary scale, spinelike scales on round spots on the flanks only in females, 22–28 subdigital lamellae under fourth toe, 80–96 scales around midbody, and 35–43 ventral scales in a longitudinal midventral row; males blackish blue with yellow or orange throat, females with a middorsal stripe and yellow round spots on flanks.

Description. Sphaerodactyline gecko with maximum SVL in males 46.7 mm (holotype), in females 49 mm (EBRG 4245). Head length 25–27% SVL in adults, proportionally longer (30–35% SVL) in juveniles and subadults; snout round in profile ( Fig. 15D ), subacuminate from above ( Fig. 15E ), relatively wide, sloping gently toward top of the head; neck slightly narrower than head and cylindrical body; limbs well developed; tail rounded in cross section, tapering toward tip, 109–112% SVL in adults, 93–104% SVL in subadults and juveniles.

Tongue relatively wide, slightly narrowing anteriorly, tip rounded with short median cleft, covered anteriorly by imbricate, scale-like papillae; anterior third bluish gray, posteriorly white. Teeth small, conical, subequal in length.

Rostral large, nearly pentagonal, visible from above, with a cleft extending medially beginning at posterior margin. Three postrostrals, the lateral two, situated above the nasals, are distinctly larger than the median postrostral; median postrostral slightly larger than adjacent posterior scales on snout. Nostril bordered by rostral, first supralabial, five circumnasals, and lateral postrostral (supranasal); circumnasals much larger than adjacent loreals. Scales on snout and in loreal region from nearly round to nearly conical, juxtaposed. Loreal scales 12–13 in a line between circumnasals and anterior margin of orbit. Scales on top of head little smaller than scales posterior to circumnasals. Scales in supraorbital region similar to, and continuous with, those on top of head. Supraciliary flap with series of slightly enlarged scales forming smooth or indented margin of eyelid, with a long spine-like scale projecting anteriorly from middle of upper margin ( Fig. 15D ). Pupil round. Supralabials 5–6, decreasing in size posteriorly, 4–6 just below centre of eye (in EBRG 4247 [ Fig. 15D ], the fourth supralabial appears divided, suggesting a seventh scale). Scales in temporal region similar to those on posterior upper part of head. Ear opening smaller than eye, subtriangular in both males, round in subadult female, long narrow opening in adult females (perhaps an artifact of fixation).

Mental large, trapezoid, with lateral margins slightly concave, anterior and posterior margins convex. Postmentals 2 or 3 (usually 2), distinctly larger than adjacent posterior scales. Scales on chin just behind postmentals, minute, granular; few series of larger, polygonal, juxtaposed scales adjacent to infralabials ( Fig. 15F ); infralabials 5, decreasing in size posteriorly, 3–5 below center of eye.

Scales on nape and sides of neck granular, continuous with those on head and body; scales on throat smooth with round posterior margins; short transitional area with the granular scales on chin. Dorsals granular, similar in size to scales on snout and top of head; several groups of four or five larger, conical scales on flanks and neck, coinciding with round spots in adult females; transition between scales on flanks and venter abrupt; scales on venter distinctly larger than dorsals, smaller on chest than on belly, smooth, rhomboidal to hexagonal, in oblique rows, forming longitudinal rows on belly; 35–43 scales along the midventral line between anterior margin of forelimbs and anterior margin of hind limbs; scales around midbody 80–98, including 16 or 17 ventrals. Preanal scales at margin of vent minute; scales on dorsum of tail smooth, narrow, tips directed posteriorly. Scales on underside of tail ( Fig. 15G ) smooth, flat, imbricate, increasing in size toward midventral line; midventral row of transversely enlarged scales, with sequence of one single median scale in contact posterolaterally with two smaller scales, followed by smaller single, median scale in contact posterolaterally with one smaller scale (Type C of Rivero Blanco 1979, or Sequence 1’1’’ of Avila-Pires 1995).

Scales on limbs granular, smooth, flat, and nearly round on anterior and ventral surfaces of thighs, and on ventral surface of shanks; lamellae under third finger 19–22 (mean = 20.5), proximal 5 or 6 enlarged, under fourth finger 20–25 (mean = 22.5), basal 7–9 enlarged, under fourth toe 22–28 (mean = 25), with two or three of 9–12 in basal segment enlarged. Fingers and toes with three lateral rows of scales distally. Claws exposed, not retractile.

Sexual dimorphism evident. In life, males with blackish blue or bluish black head; nape, neck, and forelimbs dirty yellow dorsally; body and hind limbs colored like head ( Fig. 15A ). Few pale blue spots on flanks; chin white; throat and chest yellow to orange; belly dirty white; flanks dark gray; tail dirty white to orange ventrally; iris brown; claws white. Females with wide brownish-gray vertebral stripe with blue flecks on edges, bordered by black; flanks olive green with black reticulation and yellow nearly round spots ( Fig. 15B ); head brownish green with dark brown spots; forelimbs olive green with black reticulation; venter white, except dark brown spots in gular region; tail yellowish-gray with black spots dorsally, gray bordered by black ventrally; white and black bands or rings distally ( Fig. 15C ); iris brown; claws white. Juveniles brown dorsally with or without black dorsolateral stripes; otherwise colored like females but not as bright, with small yellow spots on flanks ventral whitish ivory, almost transparent.

In preservative, the dorsum of the head and anterior part of the body in males almost uniform brown, with a paler region corresponding to the yellow area in life; narrow pale brown vertebral stripe, seen in life; venter dirty white on throat and anterior part of body (few, nearly indistinct gular marks in EBRG 4244 ); scales on flanks, limbs, and posterior part of the body white outlined by black. In holotype, midventral row of scales on tail white outlined by black; rest of ventral surface of tail pale gray, becoming dark gray with white rings distally. In EBRG 4244 , midventral row of scales on tail white outlined in black, bordered laterally by black flecks. In preservative, dorsum of females greenish brown with conspicuous vertebral stripe, bordered by irregular, slightly darker dorsolateral stripes; spots white; rings distally on tail well-defined, even dorsally, in EBRG 4246 , not so evident in EBRG 4247 , absent in EBRG 4166 . Throat and chest white with black marks on throat, most evident in larger individuals ( EBRG 4166 , 4245–56 ); scales on belly white outlined by black, creating pale gray appearance. Creamy yellow egg visible beneath translucent ventral skin in EBRG 4245 . Ventral surface of tail white with evident black rings on distal third in EBRG 4246 , not so evident and only on tip in EBRG 4247 , and absent in EBRG 4166 .

Natural history. Gonatodes superciliaris inhabits forest, where it occurs primarily in leaf litter, but also under rocks, in crevices, and amidst roots, never more than 30 cm from leaf litter. This diurnal gecko is active from 0700–1800 h. A male under a root of a huge tree grasped a cricket with his jaws, repeatedly masticated it until it was dead, and then swallowed it. A communal nest in a crevice contained 16 spherical eggs 8–9 mm in diameter, as well as some broken eggshells. Opening some of the eggs revealed that the eggs were in different developmental stages; some contained advanced embryos, whereas others apparently were more recently deposited, because no embryo was visible). Some females were carrying one egg, visible through the translucent skin and located posteroventrally and slightly to the left. Although this species is not recognized by the Ye’kwana people, they called it tamene-mü, perhaps indicating the presence of G.humeralis or G. annularis in Canaracuni.

Distribution. To date, G. superciliaris is known only from Sarisariñama-tepui. The type series came from the bottom of Sima Mayor, but another specimen collected by Omar Linares on a previous expedition (see

below) was caught in the NE sector of the massif, and we do not doubt that its distribution covers the entire massif.

Remarks. At the time that this work was in press, another species of Gonatodes was described from Guyana ( Cole and Kok 2006). The species, G. alexandermendesi , has much in common with G. superciliaris . We could not check the type series yet, and until this can be made, we still offer the description of G. superciliaris as a new species, probably endemic to Sarisariñama.

Figures

FIGURE 15. Gonatodes superciliaris sp. nov. (a) male holotype (EBRG 4243). (b) anterior half of the body of the female paratype (EBRG 4246). (c, female paratype EBRG 4246 in life, entire animal. Details of external characteristics