Cyrtodactylus sinyineensis, Grismer & Wood & Jr. & Thura & Zin & Quah & Murdoch & Grismer & Lin & Kyaw & Lwin, 2018

Grismer, L. Lee, Wood, Perry L., Jr., Thura, Myint Kyaw, Zin, Thaw, Quah, Evan S. H., Murdoch, Matthew L., Grismer, Marta S., Lin, Aung, Kyaw, Htet & Lwin, Ngwe, 2018, Twelve new species of Cyrtodactylus Gray (Squamata: Gekkonidae) from isolated limestone habitats in east-central and southern Myanmar demonstrate high localized diversity and unprecedented microendemism, Zoological Journal of the Linnean Society 182, pp. 862-959 : 925-929

CYRTODACTYLUS SINYINEENSIS SP. NOV.

SIN YINE CAVE BENT-TOED GECKO

( FIG. 28; TABLE 16)

Holotype: Adult male LSUHC 12835 collected on 5 October 2016 at 1600 h by L. Lee Grismer, Perry

Abbreviations are listed in the Material and Methods. R, right; L, left; /, data unobtainable or not applicable.

L. Wood, Jr., Matthew L. Murdoch, Myint Kyaw Thura, Evan S. H. Quah, Thaw Zin, Htet Kyaw and Marta S. Grismer from Sin Yine Cave 18.5 km south-east of Hpa-an, Hpa-an District, Kayin State, Myanmar (N16°44.605, E97°29.493; 26 m in elevation) .

Paratypes: Adult females LSUHC 12836–37 bear the same collection data as the holotype .

Diagnosis: Cyrtodactylus sinyineensis sp. nov. differs from all congeners by having the unique combination of nine or ten supralabials; eight infralabials; 15 longitudinal rows of body tubercles; 33–35 paravertebral tubercles; 27–29 ventral scales; relatively long digits with 8–10 expanded subdigital lamellae proximal to the digital inflection on the fourth toe, 11 or 12 unmodified, distal, subdigital lamellae; 19–21 total subdigital lamellae; raised, moderate to strongly keeled, dorsal body tubercles extending beyond base of tail; enlarged femoral and precloacal scales continuous; 26 or 27 enlarged femoral scales nearly equal in size; 18 femoral pores in males; 10–12 enlarged precloacal scales; five precloacal pores in males; three rows of enlarged, post-precloacal scales; median subcaudal scales twice as wide as long, not extending onto lateral surface of tail; top of head bearing diffuse dark mottling, no yellow reticulum; nuchal loop not divided medially, lacking an anterior, azygous notch, posterior border jagged; five or six dark, jagged dorsal bands wider than interspaces bearing weakly lightened centres, edged with yellow tubercles; nape band present; dark markings in dorsal interspaces variable; ventrolateral folds not whitish; anterodorsal margins of thighs and brachia darkly pigmented; nine light-coloured, caudal bands bearing dark markings, not encircling tail; and nine dark caudal bands wider than light caudal bands.

Description of holotype: Adult male SVL 88.3 mm; head moderate in length (HL/SVL 0.30), wide (HW/ HL 0.65), flat (HD/HL 0.39), distinct from neck, triangular in dorsal profile; lores inflated, prefrontal region shallowly concave, canthus rostralis rounded; snout elongate (ES/HL 0.39), rounded in dorsal profile, not flat in lateral profile; eye large (ED/HL 0.25); ear opening round, moderate in size (EL/HL 0.12); eye to ear distance greater than diameter of eye; rostral rectangular, partially divided dorsally by inverted Y-shaped furrow, bordered posteriorly by left and right large supranasals meeting on midline, laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by supranasal, posteriorly by two postnasals, ventrally by first supralabial; 10(R)9(L) square supralabials extending to below midpoint of eye; 8(R,L) infralabials tapering posteriorly to below orbit; scales of rostrum and lores slightly raised, larger than granular scales on top of head and occiput; scales on top of head and occiput intermixed with small tubercles; dorsal superciliaries not elongate or keeled; mental triangular, bordered laterally by first infralabials and posteriorly by large left and right trapezoidal postmentals contacting for 65% of their length posterior to mental; one row of slightly enlarged chinshields bordering all infralabials; and gular and throat scales small, flat, grading posteriorly into larger, subimbricate, pectoral and ventral scales.

Body relatively short (AG/SVL 0.44) with well-defined ventrolateral folds; dorsal scales small, raised and interspersed with large, conical, semi-regularly arranged, moderate to strongly keeled tubercles; tubercles extend from nape to beyond base of tail; tubercles on nape smaller than those on posterior portion of body; approximately 15 longitudinal rows of body tubercles; 33 paravertebral tubercles; 27 flat, subimbricate, ventral scales larger than dorsal scales; ten enlarged precloacal scales; five precloacal pores; three rows of large, post-precloacal scales; and no deep, precloacal groove or depression.

Forelimbs moderate in stature, relatively short (FL/ SVL 0.16); flat scales of forearm larger than those on body, not interspersed with small tubercles; palmar scales flat; digits well-developed, relatively long, inflected at basal, interphalangeal joints; digits much more narrow distal to inflections; expanded, proximal, subdigital lamellae do not extend onto palm; claws well-developed, sheathed by a dorsal and ventral scale at base; hindlimbs more robust than forelimbs, moderate in length (TBL/SVL 0.19), covered dorsally by granular scales intermixed with large tubercles and bearing flat, slightly larger scales anteriorly; ventral scales of thigh flat, imbricate, larger than dorsals, one row of 13(R,L) nearly equally sized, enlarged femoral scales in contact with enlarged precloacal scales; 9(R,L) femoral pores; subtibial scales flat, imbricate; small postfemoral scales form abrupt union with larger, flat ventral scales of posteroventral margin of thigh; plantar scales slightly raised; digits relatively long, well-developed, inflected at basal, interphalangeal joints; 8(R,L) transversely expanded subdigital lamellae on fourth toe, 11(R,L) unmodified subdigital lamellae distal to inflection, 19 total subdigital lamellae; and claws well-developed, base of claw sheathed by a dorsal and ventral scale.

Tail regenerated, 58.9 mm in length, 9.8 mm in width at base, tapering to a point; dorsal scales of tail flat; 3(R,L) enlarged postcloacal tubercles at base of tail on hemipenal swellings; and postcloacal scales flat.

Coloration in life: Dorsal ground colour of head body, and limbs dark-brown, that of posterior portion of tail whitish; top of head and rostrum darkly mottled bearing a network of diffuse, yellow markings but no reticulum; superciliary scales yellow; dark-brown, nuchal band distinct, unnotched anteromedially, bearing a jagged posterior margin; large, dark, paravertebral markings on nape; six jagged body bands bearing weakly lightened centres, wider than interspaces; one incomplete sacral band; interspaces bearing diffuse, dark markings; limbs darkly mottled not banded; thighs and brachia, darkly pigmented; ventrolateral body folds not whitish; and ventral surfaces pigmented, dusky in appearance.

Variation ( Fig. 28; Fig. S9): The female paratypes differ to varying extents from the holotype in aspects of the dorsal colour pattern. LSUHC 12836 has a complete tail with a median row of wide, transversely expanded subcaudal scales twice as wide as long; nine dark caudal bands bearing lightened centres, wider than light caudal bands; nine light caudal bands with dark spots, not encircling tail; and a dark-brown subcaudal region. LSUHC 12837 has lineate components to its dorsal pattern with a generally yellow hue and a regenerated tail with dark, irregularly shaped markings. Meristic differences are listed in Table 16.

Distribution: Cyrtodactylus sinyineensis sp. nov. is known only from Sin Yine Cave 18.5 km south-east of Hpa-an, Hpa-an District, Kayin State, Myanmar ( Fig. 20).

Etymology: The specific epithet, sinyineensis , is a noun in apposition in reference to the type locality of Sin Yine Cave.

Natural history: Sin Yine Cave is situated on the south end of a large, isolated, karst hill approximately 3.6 km wide, 16.4 km long and 338 m high that is surrounded by paddy fields and located immediately south-east of Hpa-an. Sin Yine Cave is connected to Sadan Cave as they occur along the same, semicircular karst ridge. The mouth of Sin Yine Cave is approximately 700 m away from the southern opening of Sadan Cave across an ephemerally flooded paddy field. The interior of the Sin Yine Cave is wide (~ 25 m) and it has the appropriate microhabitat (fluted stalactites and stalagmites, alcoves, cracks, small side caves, etc.) necessary for Cyrtodactylus ( Fig. 29). A total of three specimens were collected: LSUHC 12837 was 1 m above the cave floor on a stalagmite with water flowing down its face; LSUHC 12835 was seen running across the ground through water at the base of a stalagmite; and LSUHC 12836 was found 2 m above the cave floor on the cave wall. All lizards were found in close proximity (~ 15 m) to one another in near total darkness, approximately 100 m from the cave entrance .

Comparisons: Cyrtodactylus sinyineensis sp. nov. is part of the sinyineensis group. The PCA and DAPC analyses indicate that the species of this group are completely separate in morphospace where the first two principal components account for 63% of the total variation ( Fig. 12) and load most heavily for numbers of infralabials, longitudinal rows of body tubercles, expanded subdigital fourth toe lamellae and post-precloacal scale rows ( Table S3). Cyrtodactylus sinyineensis sp. nov. is well-differentiated from C. aequalis , C. dammanthaensis sp. nov. and C. welpyanensis sp. nov. by having varying combinations of statistically different mean values of infralabials, supralabials, ventral scales, enlarged femoral scales, precloacal scales; and longitudinal rows of body tubercles ( Table 3). It differs further from its sister species, C. welpyanensis sp. nov., by having dorsal bands edged with light tubercles and having a maximum SVL of 91.6 mm vs. 70.6 mm. It differs further from C. dammathetensis , and C. aequalis by lacking paravertebral elements in the dorsal banding pattern ( Table 8). Morphological and colour pattern differences from other species in the Indo-Chinese clade are listed in Table 8. Genetic distances among the species of this group range from 11.0 to 16.5% ( Table 10).