Cyrtodactylus yathepyanensis, 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 : 935-937

CYRTODACTYLUS YATHEPYANENSIS SP. NOV.

YATHE PYAN CAVE BENT-TOED GECKO

( FIG. 32; TABLE 18)

Holotype: Adult male LSUHC 12823 collected on 4 October 2016 at 1800 h by Evan S. H. Quah, Matthew L. Murdoch, L. Lee Grismer, Marta S. Grismer, Myint Kyaw Thura, Perry L. Wood, Jr., Thaw Zin and Htet Kyaw from Yathe Pyan Cave 9 km south-west of Hpa-an, Hpa-an District, Kayin State, Myanmar (N16°50.114, E97°34.243; 22 m in elevation).

Paratypes: Adult females BYU 52228–29 and LSUHC 12822 bear the same collection data as the holotype .

Diagnosis: Cyrtodactylus yathepyanensis sp. nov. differs from all congeners by having the unique combination of nine or ten supralabials; eight or nine infralabials; 18 or 19 longitudinal rows of body tubercles; 31 or 32 paravertebral tubercles; 30–32 ventral scales; relatively long digits with eight or nine expanded subdigital lamellae proximal to the digital inflection on the fourth toe, 12–14 unmodified, distal, subdigital lamellae, 20–23 total subdigital lamellae; raised, moderately to strongly keeled, dorsal body tubercles extending beyond base of tail; enlarged femoral and precloacal scales continuous; 25–34 enlarged femoral scales, proximal scales one-half to one-third the size of distal scales; 17 femoral pores in males; 10–13 enlarged precloacal scales; six precloacal pores in males; three rows of enlarged post-precloacal scales; medial subcaudal scales three times as wide as long 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 sinuous to jagged; 4–6 dark, jagged, dorsal bands lacking paravertebral elements, same width as interspaces, lacking lightened centres, edged with light tubercles; dark markings and lacking light tubercles in dorsal interspaces; ventrolateral folds whitish; anterodorsal margins of thighs and brachia darkly pigmented; 13 light caudal bands bearing dark markings, not encircling tail; 13 dark caudal bands wider than light caudal bands; and mature, regenerated tail not spotted.

Description of holotype: Adult male SVL 68.0 mm; head moderate in length (HL/SVL 0.29), wide (HW/ HL 0.72), flat (HD/HL 0.41), distinct from neck, triangular in dorsal profile; lores inflated, prefrontal region concave, canthus rostralis rounded; snout elongate (ES/HL 0.46), rounded in dorsal profile, not flat in lateral profile; eye large (ED/HL 0.25); ear opening round, moderate in size (EL/HL 0.19); eye to ear distance greater than diameter of eye; rostral rectangular, partially divided dorsally by an inverted Y-shaped furrow, bordered posteriorly by left and right supranasals contacting on midline, laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by supranasal, posteriorly by three postnasals and ventrally by first supralabial; 10(R,L) square supralabials extending to below midpoint of eye; 9(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 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 60% 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 0.41) with well-defined ventrolateral folds; dorsal scales small, raised and interspersed with large, conical, semi-regularly arranged, moderately to strongly keeled tubercles extending from nape to beyond base of tail; tubercles on nape smaller than those on posterior portion of body, less sharply keeled; approximately 19 longitudinal rows of body tubercles; 32 paravertebral tubercles; 30 flat, subimbricate, ventral scales larger than dorsal scales; 11 enlarged precloacal scales; six precloacal pores; three rows of large, post-precloacal scales; and no deep, precloacal groove or depression.

Forelimbs moderate in stature, relatively short (FL/ SVL 0.17); slightly raised scales of forearm larger than those on body, interspersed with small tubercles; palmar scales flat; digits well-developed, relatively long, inflected at basal, interphalangeal joints; digits much more narrow distal to inflections; widened, 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 0.22), covered dorsally by granular scales intermixed with large tubercles and bearing flat, slightly larger scales anteriorly; ventral scales of thigh flat, imbricate, larger than dorsal scales, one row of 16(R)17(L) enlarged, femoral scales in contact with enlarged precloacal scales; proximal femoral scales one-half to one-third the size of distal femoral scales; 9(R)8(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 raised; digits relatively long, well-developed, inflected at basal, interphalangeal joints; 9(R,L) transversely expanded subdigital lamellae on fourth toe proximal to joint inflection not extending onto sole, 14(R,L) unmodified subdigital lamellae distal to inflection, 23 total subdigital lamellae; and claws well-developed, base of claw sheathed by a dorsal and ventral scale.

Tail moderate in proportions, 71.0 mm in length, last 35.0 mm regenerated, 8.1 mm in width at base, tapering to a point; dorsal scales of tail flat; medial subcaudal scales three times as wide as long extending onto lateral surface of tail; 2(R,L) enlarged, postcloacal tubercles at base of tail on hemipenal swellings; and postcloacal scales flat.

Coloration in life ( Fig. 32): Dorsal ground colour of head body, and limbs tan, that of anterior portion of tail dull-yellow; top of head bearing, medial, diffuse dark mottling, no yellow reticulum; rostrum bearing diffuse, dark, lineate markings; superciliary scales tan; distinct, dark-brown nuchal loop, notched posteromedially not anteromedially, and bearing a sinuous posterior margin; no band on nape; four regularly shaped body bands not bearing light centres, same width as interspaces, lacking paravertebral elements; one sacral band; interspaces bearing dark markings, especially on flanks; banding on limbs indistinct, mottled with yellowish markings; anterodorsal margins of thighs and brachia pigmented; ventrolateral body folds whitish; dark caudal bands lacking lightened centres, wider than light caudal bands; light caudal bands bearing dark markings, not encircling tail; ventral surfaces pigmented, dusky in appearance; and subcaudal region gray with light mottling.

Variation ( Fig. 32; Fig. S11): The female paratypes generally approximate the holotype in aspects of colour pattern. LSUHC 12819 is somewhat darker overall and BYU 52228–29 and LSUHC 12822 have weakly pigmented, ventrolateral body folds. The nape band is present in BYU 52229 and LSUHC 12821–22 . BYU 52228 and LSUHC 128221 have original tails. Meristic and mensural differences are presented in Table 18 .

Distribution: Cyrtodactylus yathepyanensis sp. nov. is known only from Yathe Pyan Cave 9 km south-west of Hpa-an, Hpa-an District, Kayin State, Myanmar ( Fig. 20).

Etymology: The specific epithet, yathepyanensis (pronounced ya-thay-pee-an-ensis), is a noun in apposition in reference to the type locality of Yathe Pyan Cave.

Natural history: Yathe Pyan Cave is located at the south end of a karst hill approximately 1.2 km wide, 3.7 km long and 241 m high that is surrounded by paddy fields and situated just west of the Salween River. The opening of the cave is very wide and high (~ 45 m by ~ 20 m) and the cave is filled with religious structures. It extends for nearly 0.5 km and opens up again on the western side of the hill. No C. yathepyanensis sp. nov. were seen inside the cave during the afternoon at 1600 h but two were observed deep within cracks outside the cave at the base of the karst hill. This portion of the hill has several boulders, cracks and holes that serve as retreats ( Fig. 33). During the evening, only one specimen was observed at the entrance of the cave although they were quite common outside the cave. One hatchling was observed. Lizards were extremely wary and difficult to catch and when observed, all were in close proximity to retreat sites. This was quite different from other species (i.e. C. sadanensis sp. nov., C. pharbaungensis sp. nov., C. sanpelensis sp. nov. and C. linnoensis sp. nov.) we had collected in similar habitats on the hillsides outside of caves and we suspect the presence of numerous Gecko gecko , which could easily be a potential predator, could have been the reason. Other gekkonids observed were Gehyra mutilata and H. frenatus .

Comparisons: Cyrtodactylus yathepyanensis sp. nov. is part of the yathepyanensis group. The PCA and DAPC analyses indicate that the species of this group are completely separate in morphospace and that the first two principal components account for 54% of the the species of this group range from 11.0 to 12.7% ( Table 10).