Cyrtodactylus semicinctus, Harvey, Michael B., O’Connell, Kyle A., Barraza, Gabriel, Riyanto, Awal, Kurniawan, Nia & Smith, Eric N., 2015

Harvey, Michael B., O’Connell, Kyle A., Barraza, Gabriel, Riyanto, Awal, Kurniawan, Nia & Smith, Eric N., 2015, Two new species of Cyrtodactylus (Squamata: Gekkonidae) from the Southern Bukit Barisan Range of Sumatra and an estimation of their phylogeny, Zootaxa 4020 (3), pp. 495-516 : 503-507

Cyrtodactylus semicinctus sp. nov. Harvey, O’Connell, Barraza, Riyanto, Kurniawan & Smith

Holotype. An adult male ( MZB 9703, collector’s tag ENS 14958, Fig. 5 ) from montane forest on a trail above Kayu Aro, leading to the top of Mt. Kerinci, Kabupaten Kerinci, Jambi Province, Sumatra, Indonesia, 1905 m, 1.74159° S, 101.26015°E, collected on 24 June 2013 by M. B. Harvey and K. A. O’Connell.

Paratypes (7). Two males ( MZB 9695, 9696), four females ( MZB 9694, UTA R- 61576, 61577, 61588), and one unsexed juvenile ( MZB 9701) collected from the same trail as the holotype, 1752–2006 m, on 21 June 2014 by M. B. Harvey, E. N. Smith, and other members of the summer 2013 field party.

Diagnosis. A medium size species of Cyrtodactylus reaching 89 mm SVL and distinguished from all congeners by the following combination of characters: (1) body moderately robust; limbs and digits relatively long; (2) tail 1.05–1.19 times longer than body; (3) subpyramidal, weakly keeled tubercles extending from parietal region and supraorbital skin to base of tail, 24–27 irregular longitudinal rows of tubercles at midbody, 29–35 irregular transverse rows between limbs; (4) dorsal antebrachium tuberculate, brachium lacking tubercles; (5) tubercles on tail restricted to basal third; (6) 33–44 ventrals in a transverse row at midbody; (7) subcaudals not transversely enlarged; (8) deep, subtriangular precloacal depression in males; (9) 36–38 femoral and precloacal pores in males, arrayed in a continuous series (fewer pore primordia usually present in females), sunken into precloacal depression; (10) scale at anterior apex of pore-bearing scales greatly enlarged, sunken into precloacal depression in males, superficial in females; (11) pore-bearing series sharply transitioning to tiny granular scales of postaxial surface of thigh; (12) 19–22 lamellae under fourth toe; (13) cloacal tubercles 2/2 or 3/3 contacting one another; (14) dorsal pattern of brown blotches widely edged in black; tubercles on flanks yellow to pale cream; (15) labials mostly yellow; wide U-shaped band around occiput to loreal region; (16) 5–7 transverse, irregular or broken bands on body; 9–11 regular bands on tail, incomplete ventrally, except near distal tip of some specimens.

Description. Medium-size Cyrtodactylus reaching at least 89 mm SVL in females, 75 mm in males; smallest juvenile 36 mm SVL; body moderately robust, accounting for 69.9–72.9% (n = 3) of SVL in males, 70.1–74.3% (n = 4) of SVL in females; tail 1.05–1.19 (1.10 ± 0.05, n = 5) times longer than body and accounting for 51.4–54.4% (52.4 ± 1.2, n = 5) of total length; head triangular in dorsal view; head 27.1–30.1% of SVL, 62.4–71.1% as wide as long, and 37.6–40.3% as deep as wide in males (n = 3) and 25.7–29.9% of SVL, 58.7–72.3% as wide as long, and 32.7–37.1% as deep as wide in females (n = 4).

Rostral narrower than mental (76.7–99.5%, 89.5 ± 8.6, n = 8, of width of mental), posteriorly forming border of nostril; dorsal margin of rostral deeply notched medially by shallow groove; rostral bordered posteriorly by three (50%, n = 8), four (38%, n = 8), or five (12%, n = 8) postrostrals; postrostral at midline projecting into posterior margin of rostral; internarial region narrow, 17.2–21.1% (19.5 ± 1.4, n = 8) as wide as head; distance between anterior margins of orbit 29.2–39.6% (34.8 ± 3.9, n = 8) as wide as head; shallow, key-hole shaped depression occupying most of prefrontal, frontal, and parietal areas (depression bordered laterally by slightly raised canthal, circumorbital, and supratemporal ridges and thickened skin at occiput); scales on dorsal snout granular, subpyrimidal, smooth, subequal in size, and slightly larger than granules of frontal and parietal regions; tubercles extending to parietal region and on supraorbital skin but absent from snout and depressed areas between eyes; tubercles on dorsal surface of head subpyrimidal and smooth, much smaller than those on body, each surrounded by seven or eight granular scales; dorsal body tubercles unicarinate, oval, slightly projecting from dorsum, about five times as large as dorsal granules, 24–27 (25 ± 1, n = 8) longitudinal rows at midbody including scales in ventrolateral folds, 29–35 (32 ± 2, n = 8) irregular transverse rows between limbs; dorsal granules smooth.

Nostril oval, directed postero-laterally and somewhat dorsally; bordered by rostral, postrostral, supranasal, nasal, and narrow antero-dorsal process of first supralabial; supranasal rounded, about twice as large as adjacent postnasals; postnasals 4–6 (5 ± 0, n = 16); snout length 37.3–44.7% (40.8 ± 2.1, n = 8) of head length and distance from orbit to nostril accounting for 68.1–77.6% (72.7 ± 2.8, n = 8) of snout length; loreal region sloping; lips flared; 16–23 (18 ± 2, n = 8) loreals between nasal and anterior border of orbit; lorilabials in front of orbit flat, plate-like, enlarged relative to other loreals (1.5–2 times as large as loreals above them, but much smaller than supralabials); eye separated from supralabials by one or two longitudinal rows of tiny granules; diameter of orbit 20.8–26.6% (23.4 ± 2.0, n = 8) of head length; temporal region with granular scales separating large, subpyrimidal, and keeled tubercles; distance from posterior border of orbit to anterior border of auditory meatus 27.0–33.3% (29.7 ± 2.3, n = 8) of head length; auditory meatus deep, narrowly elliptical, directed postero-dorsally at about 30° to vertical, positioned at posterior end of head and with its ventral margin at same level as rictus; smallest diameter of auditory meatus 60–70% smaller than greatest diameter; enlarged supralabials 8–11 (10 ± 1, n = 15), last separated by 2–4 small granular scales from rictus (10–15 total supralabials; 7–9 from center of orbit to rostral); first supralabial with antero-dorsal extension reaching nostril and separating lorilabials from rostral; remaining supralabials subrectangular with rounded dorsal edges, reducing in size to rictus.

Mental triangular; infralabials 8–10 (9 ± 1, n = 15; 6–7 from center of orbit); pair of postmentals in contact medially; second pair of postmentals squarish, about half as wide as first pair, separated from one another medially by 6–8 (7 ± 1, n = 8) small granular scales bordering first pair of postmentals; sublabial row decreasing in size posteriorly; gulars small, smooth, granular, nonimbricate, much smaller than ventrals; gulars grading into progressively larger, imbricate scales just in front of pectoral girdle; scale of chest like ventrals; ventrals smooth, imbricate, flat, circular, slightly smaller than tubercles on dorsum, but much smaller than dorsal granules; ventrals in transverse row at midbody 33–44 (38 ± 5, n = 6); ventrolateral skin fold distinct, containing tubercles.

Tail subcylindrical, though somewhat flattened dorsally and ventrally; tubercles restricted to 17.2–23.3% of intact tails (n = 2); distribution of tubercles at base of tail like dorsal body, distally tubercles not projecting and arrayed in 1–5 verticils; verticiles separated by 5–7 small scales along dorsal midline; tubercles on tail not extending to ventral side, although some scales of verticils may be slightly enlarged relative to other subcaudals; subcaudals flat, homogenous, two or three times as large as scales on sides of tail; each subcaudal about as long as wide; transversely enlarged subcaudal plates absent; in specimens with regenerated tails, subcaudals just proximal to regenerated portion enlarged: about half again as long as scale row proximal to them; cloacal tubercles rounded, smooth, two (88%, n = 16) or three (12%, n = 16, both counts of three in one specimen: UTA R-61577), in contact with one another, half again as large as dorsal tubercles; tip of tail capped by granular scales.

Brachium covered in small, homogenous, weakly keeled scales; brachial tubercles absent; antebrachium tuberculate; antebrachial tubercles subpyrimidal, unicarinate, about four times as large as granular scales between them, slightly smaller than those on dorsum; ventral surfaces of brachium and antebrachium covered in smooth, slightly imbricate, homogenous scales; scales on palm and dorsal surface of hand granular, smooth, weakly (ventrally) to moderately (dorsal surface) imbricate; scales under finger I 8–10 (n = 8 for all digits), under finger II 12–15, under finger III 15–17, under finger IV 16–18, under finger V 12–15 (all counts excluding ungual scale); one or two scales widened and similar to lamellae extending onto palm at base of digits.

Thigh, shank, and postaxial half of dorsal foot (at base of toes IV–V) tuberculate; tubercles of leg subpyrimidal, unicarinate, about same size as those on dorsum, about five times as large as small granular scales between them; preaxial and ventral surface of thigh covered in rounded, flat, imbricate scales; ventral thigh with enlarged row of pore-bearing scales and similarly enlarged row of scales anterior to pore-bearing row; this doubled row of scales arranged in an inverted V with its apex at midline of belly; abrupt transition to tiny granules on postaxial surface of thigh; postfemoral granules only one-fifth to one-sixth size of pore-bearing scales; sole covered in flat, imbricate, rounded scales; scales under toe I 8–11, under toe II 12–15, under toe III 17–19; under toe IV 19– 22, under toe V 17–20; one or two scales widened and similar to lamellae extending onto sole at base of digits.

Arrangement of pore-bearing scales sexually dimorphic; both sexes with single, greatly enlarged scale at apex of pore-bearing series; apical scale twice as long as wide, with single pore or pore primordium at its posterior end; apical scale superficial in females and juveniles, sunken into precloacal depression in males; total pores 36 and 38 in two adult males (SVL 75 mm and 68 mm, respectively), only 14 in small male (SVL 55 mm) perhaps due to ontogenetic differences; two females (SVL 51 mm and 89 mm, respectively) with 17 and 19 pore primordia, one lacking primordia (SVL 83 mm); in both sexes pores and/or primordia extending onto thigh.

Coloration. In life, Cyrtodactylus semicinctus has a light gray, greenish tan, or dull orange ground coloration with brown to reddish brown markings widely edged in black (MZB 9695 was in the process of shedding and its ground coloration was gray rather than orange or greenish tan). Narrow markings are entirely black. The dorsal tubercles are a paler shade than the dorsal ground color. On the flanks, even some of the tubercles within dark markings are this pale color, so that the flanks appear to be densely speckled. A yellow wash covers the labials, rostral, and supraciliary scales. These yellowish scales are mostly immaculate, although small, irregular black blotches mark the narial and internarial region and sometimes extend ventrally onto the rostral and or first supralabial. Dorsally, the head usually has one to three poorly defined blotches in the parietal region and a sharp black line edging the gray to yellow supraciliaries medially. This species has a distinctive U-shaped marking extending from the loreal regions around the occiput. The marking begins a short distance behind the nasal just above the enlarged series of lorilabials and widens just in front of the eye. Behind the eye and around the occiput, a slightly more narrow pale band edges the U-shaped band dorsally and accentuates it.

The iris is reddish brown to greenish bronze, edged in black and with a black reticulum. The ciliary body is only slightly lighter than the iris and indistict.

Cyrtodactylus semicinctus ( Fig. 6 ) has one band on the neck, 5–7 (6 ± 1, n = 8) bands on the body, and 9–11 (10 ± 1, n = 5) bands on the tail. Bands on the neck and body are jagged, irregular, and frequently broken on the flanks. When broken, blotches on the flanks may fuse with one another, sometimes to produce long sinuous markings. In particular, the band on the neck usually breaks up into blotches. However, the band on the neck does not fuse to the U-shaped nuchal band. Bands on the tail are slightly longer than the pale interspaces. Except near the distal tip of the tail of some specimens, the bands are not continuous ventrally (i.e., the tail is banded, not ringed; all specimens have at least the basal one-third of the tail not regenerated and none have ringed tails). Distally, the caudal interspaces become increasingly more pale. Regenerated tails are entirely black or mostly black with few scattered cream scales. The brachium, antebrachium, thigh, and shank each bears two or three jagged, irregular bands.

Except for the tail, the venter is mostly rose pink to grayish purple. Palms and soles are a darker shade of the same ground color, whereas the pore-bearing series are distinctly paler than scales around them. Some scales at the edges of the venter are the same color as the dorsal ground coloration. They form a diffuse reticulum against the rose pink to grayish purple ground color. This diffuse, greenish tan to orange reticulum is restricted to the lateral edges of the belly and pre- and postaxial margins of the ventral limbs, but extends across the entire gular region. The cloacal tubercles are greenish tan or orange. Ventrally, intact tails are tessellated with charcoal and elements of the dorsal ground coloration.

Etymology. This species’ name semicinctus is a masculine adjective derived from the Latin noun cinctum, meaning girdle or belt, and prefix semi, meaning partial or incomplete. The name alludes to the incomplete caudal rings of this species.

Standard English name. Kerinci Bent-toed Geckos.

Standard Indonesian name. Cicak Jari Lengkung Kerinci.

Distribution and natural history. This species is known only from the type locality. We collected the entire type series between 1752–2006 m along a trail above the tiny hamlet of Kayu Aro. The trail extends through apparently pristine forest to the top of Mt. Kerinci and is frequented by hikers. Field parties collected Cyrtodactylus semicinctus on the forest floor at night (1950–2340 hrs) and we found most specimens around tree trunks. In field notes, Harvey noted that UTA R-61576 emitted a faint “baaap” when first grasped and a louder “raaank” when struggling as the senior author collected color notes.

Figures

FIGURE 5. Adult male holotype (A, MZB 9703, head length 20.5 mm) and adult female paratypes (B, UTA R- 61588, SVL 47 mm; C – D, MZB 9694, SVL 83 mm) of Cyrtodactylus semicinctus from montane forest on trail above Kayu Aro, leading to top of Mt. Kerinci, Jambi, Sumatra, Indonesia.

FIGURE 6. Dorsal and ventral color variation within the type series of Cyrtodactylus semicinctus (from left to right, same specimens in bottom row: MZB 9694, 9696, 9703 (holotype), 9695, and 9701).