Luperosaurus sorok, Das, Indraneil, Lakim, Maklarin & Kandaung, Pius, 2008

Das, Indraneil, Lakim, Maklarin & Kandaung, Pius, 2008, New species of Luperosaurus (Squamata: Gekkonidae) from the Crocker Range Park, Sabah, Malaysia (Borneo), Zootaxa 1719, pp. 53-60 : 54-60

publication ID	https://doi.org/ 10.5281/zenodo.274183
DOI	https://doi.org/10.5281/zenodo.6231769
persistent identifier	https://treatment.plazi.org/id/0389BE6A-FFF2-EA3E-83E9-FB6B049AFE41
treatment provided by	Plazi
scientific name	Luperosaurus sorok
status	sp. nov.

Treatment

Luperosaurus sorok sp. nov.

( Figs. 1–5 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 )

Holotype: SP 0 6618, female, from near bank of Sungai Bariawa, Crocker Range Park (05º24'177"N, 116º07'897"E; Fig. 6 View FIGURE 6 ), Keningau District, Sabah, Malaysia (Borneo), collected 19 February 2002 by Pius Kandaung.

Diagnosis: A small species of Luperosaurus (SVL 34.7 mm), diagnosable from congeneric species by the possession of the following combination of characters: body robust; head narrower than body; auricular opening oval-squarish; subrictal tubercles present; two intersupranasals contacting rostral; rostral contacts nares; nine supralabials to the middle of the orbital; 14/15 supralabials to posterior edge of orbit; 11 infralabials; 1–3 anteriormost chin scales subequal, larger than those to their posterior; dorsal body scales rounded, convex and granular; ca. 104 dorsal scale rows; 45 ventral scale rows; ca. 149 midbody scale rows; ventrolateral body tubercles spinose; three distal scansors deeply notched; tail fringe with distinct serrations; and pale rounded spots present on middorsum.

Description of holotype: A small bodied species of Luperosaurus (SVL 34.7 mm); snout short (HL/SVL ratio 0.18), fairly wide (HW/SVL ratio 0.18), depressed (HD/HL ratio 0.75); snout tip tapered and rounded in dorsal and lateral aspects; head distinct from neck; supraorbital crest prominent; interorbital region flattened, traversed by 24 scales; snout less than twice eye diameter (ED/E-S ratio 0.64); scales on snout and forehead small, rounded, keeled, with larger, scattered scales; scales on snout larger than those on occipital region; enlarged spinose tubercles in postocular region; eyes large (ED/HL ratio 0.36); orbits of eyes lacking ‘extrabrillar fringes’ (of Underwood, 1954); canthus rostralis weakly concave, lores sloping; pupil vertically elliptical, with crenulated edges; no elongate supraciliaries; auricular opening deep, oval-squarish (EL/E-S ratio 0.02); auricular opening with a single, pale, enlarged lobule on top of ear opening; eye to ear distance greater than diameter of eyes (E-E/ED ratio 1.32); spinose subrictal tubercles, set obliquely along mandible, forming an irregular row; no tubercles anterior to tympanum; rostral trapezoidal, lacking a rostral groove; rostral about half as deep as wide (width = 1.5 mm, depth = 0.8 mm; width/depth ratio 1.9), contacted posteriorly by narial opening, an intersupranasal, and two supranasals that are in narrow contact ventro-posteriorly with Supralabial I; individual nares oval, oriented laterally, in contact with rostral, supranasal, Supralabial I, and two postnasals; two squarish intersuprarostrals bordering rostral separate supranasals; three postnasals bound nasal; three scale rows separate orbit from supralabials; supralabial IX (L/R) in midorbital position, followed by 6/5 (L/R) smaller supralabials to point of posterior orbit of eye; infralabials 11 to edge of jaws; mental subtriangular, slightly deeper than wide; 1–3 postmentals, rounded, smaller than mental, subequal, 2–3 times larger than those to their posterior; tongue narrowly elongate, with a weak median cleft; enlarged extracranial endolymphatic sac present on nuchal region.

Head and body robust; body dorsoventrally flattened, relatively stout, somewhat elongate (A-G/SVL ratio 0.51); dermal spines and cutaneous expansion of axilla-groin region absent; tubercles on dorsum low, rounded, in irregular rows; body scales juxtaposed, lacking interstitial granules; scales along the vertebral region not differentiated; ventrals smooth, imbricate; chin shields smaller than ventrals; scales on gular, pectoral and abdominal regions subequal; dorsal scales at midbody much smaller than ventral scales; ca. 149 transverse body scale rows; 45 enlarged ventral scales; distinct demarcation between enlarged, flattened, ventral scales and the smaller, more rounded dorsal scales on lower flanks; ventrolateral body tubercles spinose; scales on ventral surfaces of manus and pes smooth, rounded; scales on inner surface of fore- and hindlimbs conical; those on outer surface of fore- and hindlimbs weakly spinose; on preanal region, scales on anteroventral surfaces as large as those on venter of body, while those on posteroventral surfaces, closer to cloaca, much smaller; femoral scales undifferentiated in size; preanal depression or groove absent; preanofemoral pores absent, but preanofemoral scales enlarged, differentiated; cloacal orifice bowed posteriorly, bordered anteriorly with a bowed integumentary fold; postcloacal glandular openings posterior to vent absent.

Forelimbs moderately short, stout; forearm short; hindlimbs short and stout; tibia short (TBL/SVL ratio 0.15); digits relatively long, weakly dilated, all clawed except for Finger I, which exhibits a small, recurved claw inside its digital tip; scansors narrow, subrectangular, unnotched, except for the 3–4 most distal scansors that are distinctly notched; basal subdigital lamellae fragmented up to mid-level of each digit; enlarged lamellae (inclusive of terminal one) numbering on manus I (5/4); II (8/8); III (11/11); IV (9/11); and V (9/9); and on pes I (8/8); II (12/11); III (10/10); IV (8/10); and V (10/19); on Finger IV and Toes III and IV, non-enlarged scales reach around midlevel of respective phalange; interdigital webbing present between all adjacent phalanges, extending beyond the mid-level of Toes III and IV; relative length of digits (finger): IV> III> V> II> I; (toe): IV> III> V> II> I; anterior edges of forearm with a weak dermal fringe; anterior edge of hindlimb at both femur and tibia lacking dermal fringe; posterior edge of forearm with a weak cutaneous fringe extending from the carpal region to axilla; posterior edge of hindlimbs with a distinct dermal fringe, extending from the base of pes below Toe V to base of thighs, and is widest at level of the knee joint, and with a distinct notch ca. 10% fringe length towards inner edge; cutaneous expansions with small, subimbricate scales; a single large pale spine on outer surface of tarsus.

Tail, original, subcylindrical at base, with a weak basal constriction and slightly flattened dorsoventrally (TW/TD ratio = 1.8) along rest of tail body, shorter than snout-vent length (TL/SVL ratio 0.69); tail body slen- der, gradually tapering; lateral margins of tail with regular serrations, each "tooth" composed of 7–8 scales forming 18 enlarged spinous fringed structures on each side of tail, the peripheral ones, especially those towards distal portion of tail being the least serrate; tail terminates in a rounded point; a single, small, cloacal spur on each side of vent; tail covered with small, cycloid scales and weakly segmented, with 5–10 irregular, transverse rows of enlarged, spinous scales; remaining caudals small, granular; subcaudals more flattened, cycloid; median subcaudal series not transversely enlarged, only slightly larger than adjacent scales; scales on postcloacal region and base smaller than on rest of tail; a low median tail furrow but no lateral tail furrows; a small spinous postcloacal spur on each side of tail.

Measurements (in mm): SVL 34.7; TL 23.9; TW 4.1; TD 2.3; BW 8.4; FA 4.4; CL 5.3; TBL 5.1; A-G 17.8; HL 6.1; HW 6.3; HD 4.6; ED 2.2; E-S 3.4; E-N 2.8; IO 3.7; EL 0.07; IN 1.5; TIVL 3.6; and TIVW 1.1 mm.

Pholidosis: Supralabials (midorbital) 9/9; infralabials 11/11; interorbitals 24; dorsal scale rows ca. 104; transverse body scale rows ca. 149; and enlarged ventrals 45.

Coloration: Pale gray dorsally, with dark gray double chevron-marks that are fused middorsally, numbering one on forehead, four on torso, between nuchal and caudal constriction, and one on pelvic region; the last comprising two isolated, subtriangular patches; six dark transverse caudal bands on dorsum of tail; each of these dark areas on dorsum edged with black; dorsal surfaces of limbs pale gray, with dark bands; lateral fringes of tail pale gray, paler than the body of tail; chin pale, unpigmented; throat yellowish-cream, with darker speckles; rest of venter, including pectoral and abdominal region as well as under surfaces of limbs and tail yellowish-cream, with darker variegation; and undersurface of tail yellowish-cream, with darker smudges. Color in life unknown.

Etymology: Derived from Malay, meaning "to hide", in reference to its presumed ecologically cryptic nature.

Ecology: Nothing is known of the natural history of the new Luperosaurus sorok . The holotype was collected from a secondary forest within the Park, and was discovered on a wet rock, on a cloudy and windy day. Crocker Range Park itself includes a large area of primary forest, encompassing both submontane and montane vegetation, and has a rich herpetofauna (discussed in Das, 2006; Hee et al., 2004).

Comparisons: The new species from Sabah is compared with congeners for Borneo and other parts of south-east Asia (see also Rősler, 2000; Kluge, 2001).

Luperosaurus sorok sp. nov. differs from L. yasumai Ota, Sengoku , & Hikida, 1996 (distribution: eastern Kalimantan, Indonesia) by the presence of a tail fringe with distinct serrations (vs. tail fringe with an irregular outline); head narrower than body (vs. subequal); auricular opening oval-squarish (vs. horizontally elongated); intersupranasals 2 (vs. 3); subrictal tubercles present (vs. absent); and pale rounded spots on middorsum (vs. indistinct, cloudy markings on middorsum). The new species differs from L. browni Russell, 1979 (distribution: Sarawak, Kalimantan, West Malaysia and Singapore; see Ota et al., 1996; K. K. P. Lim and N. T.-L. Lim, 2006) by the possession of convex (vs. flattened) dorsal scales; lateral edges of tail fringed with regularly arranged scales grouped into saw-like tooth (vs. isolated spinous scales); head narrower than body (vs. subequal); intersupranasals 2 (vs. 1); genials enlarged (vs. undifferentiated); and midbody scales number ca. 149 (vs. 129).

In this section, we compare the new species from Sabah with populations from Sumatra, Sulawesi, and the Philippines. Only opposing suite of characters are listed: brooksi Boulenger, 1920 (distribution: Sumatra, Indonesia), subrictal tubercles absent; genials small; and a single intersupranasal contacting rostral; corfieldi Gaulke, Roesler , & Brown, 2007 (distribution: Panay, Philippines), wide cutanaeous expansion on anterior forelimbs present; enlarged ventrolateral tail tubercles absent; spinous scales on edges of anterior cutaneous expansions of limbs present; females with 11 preanal pores; and dorsum with three dark chevrons between fore- and hindlimbs; cumingi Gray, 1845 (distribution: Luzon, Philippines), infralabials 13–15; preanofemoral pores 15–20; scansors on Toe I, 11–14; on Toe III, 13–16; ventrals small, granular; wide flaps on anterior edge of forelimbs; dermal fringe present on both anterior and posterior edges of hindlimbs; and subrictal tubercles absent; iskandari Brown, Supriatna , & Ota, 2000 (distribution: Sulawesi, Indonesia), dorsal body scales flat, hexagonal; anterior forelimbs with wide flaps; a single intersupranasal contacts rostral; penultimate scansors bowed; and tail lacks lateral tubercles; joloensis (Taylor, 1918) (distribution: Jolo and Mindanao, Philippines); auricular opening narrow, oblique; enlarged genials; a single intersupranasal contacts rostral; spine-like laterals; and subrictal tubercles absent; kubli Brown, Diesmos , & Duya, 2007 (distribution:

Luzon, Philippines), a gigantic species (at 105.4 mm SVL, is over thrice as large as the holotype of the new species); a single intersupranasal contacts rostral; preanofemoral pores 16; subrictal tubercles absent; scansors on Toe I, 12; on Toe III, 16; ventrals granular to subimbricate; and tail lacks lateral tubercles; macgregori (Stejneger, 1907) (distribution: Babuyan and Calayan, Philippines), digital dilation extensive; genials small; and subrictal tubercles absent; and palawanensis ( Brown & Alcala, 1978) (distribution: Palawan, Philippines), dorsum with spear-head-like scales; penultimate scansors bowed; supralabials 11–13; and preanofemoral pores 28–32.