Cyrtodactylus serratus, Kraus, Fred, 2007

Kraus, Fred, 2007, A new species of Cyrtodactylus (Squamata: Gekkonidae) from western Papua New Guinea, Zootaxa 1425, pp. 63-68 : 64-66

Cyrtodactylus serratus sp. nov.

Fig. 1

Holotype.—AMS R127707 (field tag 33910), mature male, collected by H. G. Cogger at Tabubil, 9º15'S, 152º12'E, West Sepik Province, Papua New Guinea, 30 March 1987.

Diagnosis.—A large (139 mm SV) species of Cyrtodactylus having highly raised, dentate tubercles arrayed along the length of each skin fold; approximately 10–11 regular rows of dorsal tubercles between lateral skin folds; large number (n = 87) of precloacal and femoral pores in a single series forming a shallow Vshape anterior to the cloaca; enlarged scales present anterior and posterior to the row of precloacal pores; small, divided scales under the tail; regular whorls of six enlarged tubercles arrayed along the length of the tail; uniformly sized scales on throat; and a color pattern consisting of a dark chevron on the nape followed by three pairs of dark brown ovals on body and six dark bands on tail.

Comparisons with other species.— Cyrtodactylus serratus can be immediately distinguished from all other Papuan members of the genus by its row of prominent, dentate tubercles along the lateral skin folds ( Fig. 1 C). It may be further distinguished from C. aaroni Günther & Rösler , C. louisiadensis (de Vis), and C. murua Kraus & Allison in having highly divided (vs. wide, undivided) subcaudal scales; from C. sermowaiensis (de Rooij) in its much greater size and in having (vs. lacking) precloacal and femoral pores; from C. marmoratus (Kuhl) and C. papuensis (Brongersma) in having the precloacal pores arrayed in a shallow (vs. sunken, highly compressed) chevron-shaped series; from C. irianjayensis Rösler in having many more precloacal-femoral pores (87 vs. 7–16); from C. mimikanus (Boulenger) in having the precloacal-femoral pores arrayed in continuous (vs. discontinuous) series; from C. novaeguineae (Schlegel) in lacking (vs. having) tubercles on the throat; and from C. derongo Brown & Parker and C. loriae (Boulenger) in having fewer dorsal rows of enlarged tubercles (10–11 vs. 20–22).

Description of holotype: A mature male. Animal large (SV = 139 mm, TrL = 62 mm); tail entire and curled along distal half, 158 mm. Head relatively long (HL/SV = 0.30) and wide (HW/HL = 0.75), not depressed (HH/HL = 0.41), distinct from neck ( Fig. 1 A). Loreal region inflated; canthus rostralis absent. Interorbital region and top of snout concave. Snout relatively long (SN/HL = 0.42), much longer than eye diameter (SN/EY = 1.8). Eye relatively large (EY/HL = 0.23); pupil vertical, with crenellated margins; supraciliaries large, frill-like, well-differentiated from and approximately 2–3 times larger than adjacent granules. Ear opening small (Ear/HL = 0.085), dorsoventrally compressed and overlain by skin fold; distance between ear and eye larger than eye diameter ( Fig. 1 B). Rostral almost two-thirds (4.2 mm) as high as wide (6.4 mm), highest just medial to nares and slightly depressed between these points; length (1.5 mm)>one-third height; partially divided dorsally by sinuous, weak rostral groove. Two enlarged supranasals separated by single internasal. Rostral in contact with first supralabials, two supranasals, and one internasal. External nares circular; each bordered by rostral, supranasal, first supralabial, and one nasal. First supralabial has a short extension that reaches dorsally to posterioventral margin of naris. Nasal bordered posteriorly by five small postnasals. Six or seven rows of small scales separate orbit from supralabials at narrowest point. Mental triangular, wider (5.2 mm) than long (3.1 mm). Mental bordered posteriorly by two enlarged postmentals, which are separated from each other by an elongate median scale that also abuts the mental anteriorly. First 5–6 infralabials bordered by enlarged, elongate scales, these followed posteriorly by granules. Supralabials to mid-orbital position eight on right side, nine on left; to angle of jaw ten on right, 11 on left. Infralabials ten on right, 11 on left. Scale rows between center of orbits ~65.

Body somewhat gracile (TrL/SV = 0.45), with well-developed ventrolateral skin folds consisting of highly raised, acutely dentate, enlarged tubercles separated from each other by 1–4 granules ( Fig. 1 C). Dorsal scales on head, body, and limbs tiny, juxtaposed granules; these smaller anteriorly than posteriorly. Enlarged tubercles present on head, body, limbs, and tail; best developed posteriorly; each low anteriorly and raised posteriorly; most with posterior keel, but some smooth. Ventral scales flat and smooth, those on chin and throat smaller than on abdomen. Tubercles arranged in approximately 10–11 longitudinal rows between the lateral folds; very sparse laterally and running entire length of torso only immediately adjacent to vertebral column.

Precloacal and femoral pores 87, well-developed, in single unbroken series creating a shallow V whose apex points anteriorly ( Fig. 1 D). Scales of precloacal and femoral regions enlarged and distinct from those on abdomen; five rows of enlarged scales posterior to precloacal pores; no enlarged scales posterior to femoral pores ( Fig. 1 D). No precloacal groove. Scales on palms and soles flat to slightly rounded, smooth.

Fore- and hindlimbs relatively well-developed (FA/SV = 0.15, CS/SV = 0.20). Digits well-developed, reflected at basal interphalangeal joints; all with robust, slightly recurved claws surrounded by two scales. Subdigital lamellae narrow and smooth, expanded proximally. Lamellae of manus 19–20–23–24–19 on right,?–21–23–23–21 on left; of pes 18–22–25–27–26 on right, 19–23–27–27–26 on left; first finger of left manus damaged. Relative lengths of digits on manus and pes I <V <II <III <IV. No interdigital webbing on manus, basal webbing on pes.

Tail entire, narrow (TW/SV = 0.060), tapering to a point; subcaudals highly divided small scales, same size as or only slightly larger than laterally adjacent scales. Cloacal sacs swollen, with external orifices approximately 4–5 scales wide and situated near lateral margins of vent. Scales of tail small, flat, smooth, subimbricate; with six rows of enlarged tubercles dorsally and laterally. Tubercles decreasing in prominence posteriorly and arrayed in regular whorls. Two enlarged postcloacal spurs on each side of tailbase.

Color in preservative: Dorsal ground color brown with slightly pink cast, with one chocolate-brown chevron on nape whose poorly defined arms are heterocontinuous with main body of chevron and fail to reach to each eye. Nape chevron followed on torso by three pairs of elongate blotches of same color ( Fig. 1 A) and six dark brown bands on tail. Enlarged mid-dorsal blotches with irregular margins, narrowly separated from opposite member, and with slightly darker brown margins. Top of head dark brown but lighter than chevron on nape. Limbs and remainder of torso with obscure darker brown mottling. Labials lighter than remainder of head, with white ground, but heavily stippled with brown ( Fig. 1 B). Venter brown, darker under hindlimbs and tail. Dorsal tubercles same color as surrounding granules, but dentate tubercles along the lateral skin folds dirty white or light gray, contrasting with adjacent scales ( Fig. 1 C). Postcloacal spurs white with brown stippling, contrasting with surrounding brown scales.

Measurements (in mm). – SV = 139, TrL = 62, TL = 158, TW = 8.4, FA = 21.1, CS = 27.9, HL = 41.3, HW = 31.1, HH = 17.0, Ear = 3.5, EE = 14.0, EY = 9.6, SN = 17.5, EN = 13.8, IN = 6.1, IO = 11.6.

Va r ia ti o n. – Known only from the holotype.

Etymology. – The trivial epithet is a masculine Latin adjective meaning “toothed like a saw” and refers to the enlarged lateral tubercles of the species, which impart a dentate appearance to the animal when viewed from above.

Range. – Known only from Tabubil, West Sepik Province, Papua New Guinea ( Fig. 2 ).

Figures

FIGURE 1. Photograph of (A) dorsum, (B) side of head, (C) dentate lateral tubercles, and (D) precloacal region of holotype of Cyrtodactylus serratus, AMS R 127707, from Tabubil, Papua New Guinea.

FIGURE 2. Map of New Guinea showing type locality for Cyrtodactylus serratus (closed circle).