Cyrtodactylus aunglini, Grismer & Wood & Thura & Win & Grismer & Trueblood & Quah, 2018

Grismer, L. Lee, Wood, Perry L., Thura, Myint Kyaw, Win, Nay Myo, Grismer, Marta S., Trueblood, Llyod A. & Quah, Evan S. H., 2018, A re-description of Cyrtodactylus chrysopylos Bauer (Squamata: Gekkonidae) with comments on the adaptive significance of orange coloration in hatchlings and descriptions of two new species from eastern Myanmar (Burma), Zootaxa 4527 (2), pp. 151-185 : 158-164

Cyrtodactylus aunglini sp. nov.

Kyauk Nagar Cave Bent-toed Gecko

( Figs. 2 , 3 )

Holotype. Adult male LSUHC 13947 collected on 24 March 2018 at 1030 hrs Myint Kyaw Thura, Aung Lin, Perry L. Wood, Jr., Aung Lin Htet, and L. Lee Grismer from Kyauk Nagar Cave , 11 km southwest of Pyin Oo Lwin , Pyin Oo Lwin Township, Pyin Oo Lwin District, Mandalay Region, Myanmar (20.93087°N, 95.22580°E; 715 m in elevation).

Paratypes. Adult males LSUHC 13946 , and 13948–52 bear the same collection data as the holotype .

Additional specimens examined. Hatchlings LSUHC 13943–45 bear the same collection data as the holotype.

Diagnosis. Cyrtodactylus aunglini sp. nov. differs from all other species of Cyrtodactylus by having the unique combination of the following characters: 8–10 supralabials and infralabials; 36–45 paravertebral tubercles; 21–26 longitudinal rows of body tubercles; well-developed body tubercles not extending past the hemipenial swellings; no gular tubercles; a ventrolateral fold; 41–49 ventral scales; digits not relatively short; basal subdigital lamellae expanded proximal to digital inflection; 19–23 subdigital lamellae on the fourth toe; no enlarged femoral scales or pore-bearing femoral scales; no precloacal groove; 12 or 13 pore-bearing, contiguous, precloacal scales; precloacal scale row not sharply angular; multiple enlarged post-precloacal scales; three or four cloacal spurs in males; caudal scales arranged in poorly defined segments; no enlarged, plate-like, medial subcaudal scales; band on nape; seven or eight dorsal bands lacking paravertebral elements, zig-zag to regular in shape, usually wider than immaculate interspaces, not bearing lightened centers, not edged posteriorly with light-colored tubercles, and posterior borders bold and anterior borders diffuse; clusters of enlarged, light-colored scales usually in ventrolateral fold; top of head generally unicolor; nine or 10 immaculate light caudal bands not encircling tail; nine or 10 dark caudal bands wider than light caudal bands; raised, moderately keeled body tubercles; and a maximum SVL of 81.6 mm ( Tables 4, 5). These characters are scored across all species in the gansi group in Table 3.

Description of holotype. Adult male, SVL 78.6 mm; head moderate in length (HL/SVL 0.28), width (HW/HL 0.61), somewhat flattened (HD/HL 0.40), distinct from neck, triangular in dorsal profile; lores inflated, prefrontal region concave, canthus rostralis rounded; snout elongate (ES/HL 0.41), rounded in dorsal profile; eye large (ED/ HL 0.20); ear opening oval, moderate in size (EL/HL 0.10); eye to ear distance greater than diameter of eye; rostral rectangular, depressed medially, divided dorsally, bordered posteriorly by large left and right supranasals separated by an internasal, laterally by external nares and first supralabials; external nares bordered anteriorly by rostral, dorsally by one large anterior and one smaller posterior supranasal, posteriorly by five small postnasals, ventrally by first supralabial; nine (R) eight (L) rectangular supralabials extending to below midpoint of eye; 10 (R) 9 (L) infralabials tapering smoothly to below posterior margin of orbit; scales of rostrum and lores slightly raised, slightly larger than granular scales on top of head and occiput; scales on top of head and occiput intermixed with slightly enlarged tubercles; dorsal supraciliaries raised and pointed; mental triangular, bordered laterally by first infralabials and posteriorly by large, left and right trapezoidal postmentals that contact medially for 30% of their length posterior to mental; one row of slightly enlarged chinshields extending posteriorly to third infralabial; and gular and throat scales small, granular, grading posteriorly into larger, flatter, smooth, subimbricate to imbricate, pectoral scales that grade posteriorly into larger and imbricate ventral scales.

Body relatively short (AG/SVL 0.42) with well-developed ventrolateral folds; dorsal scales small, interspersed with larger, weakly keeled, semi-regularly arranged tubercles; tubercles extend from top of head onto base of tail with well-developed tubercles extending no farther than the posterior margin of the hemipenial swellings; tubercles on occiput and nape smaller than those on posterior portion of body which are larger and keeled; approximately 21 longitudinal rows of dorsal tubercles; 37 paravertebral tubercles; approximately 41 flat, imbricate, ventral scales larger than dorsal scales; 12 contiguous, pore-bearing precloacal scales that are not in a sharply angled row; seven large post-precloacal scales with no greatly enlarged medial scale; precloacal groove or depression absent; and three cloacal spurs on each side of hemipenial swelling.

Forelimbs moderate in stature, relatively short (FL/SVL 0.13); raised scales of forearm same size as those on body, interspersed with large tubercles; palmar scales slightly raised; digits well-developed, inflected at basal, interphalangeal joints, slightly narrower distal to inflections; claws well-developed, sheathed by a dorsal and ventral scale; enlarged series of scales at base of first digit; hind limbs more robust than forelimbs, moderate in length (TBL/SVL 0.17), covered dorsally by granular scales interspersed with large, keeled, tubercles and anteriorly by large, flat, imbricate scales; ventral scales of thigh flat, imbricate, slightly larger than dorsals, lacking a row of enlarged or pore-bearing scales; small postfemoral scales grade smoothly into large, flat ventral scales of posteroventral margin of thigh; subtibial scales large, flat, imbricate; plantar scales raised; digits well-developed, inflected at interphalangeal joints; six expanded subdigital lamellae on fourth toe proximal to inflection, 13 more narrow subdigital lamellae distal to inflection, 19 total subdigital lamellae; and claws well-developed, base of claw sheathed by a dorsal and ventral scale.

Original tail moderate in proportions, 88.0 mm in length, 7.7 mm in width at base, tapering to a point, posteriormost 15.6 mm regenerated; dorsal scales of base of tail small, raised but rapidly transition into larger, flatter scales posteriorly; caudal scales arranged in poorly defined segments delimited anteriorly and posteriorly by slightly enlarged scales; and two longitudinal rows of median, subcaudal scales that do not extend onto lateral margin of tail.

Coloration in life ( Fig. 2 ). Dorsal ground color of head body, limbs, and tail brown; top of head nearly unicolor, bearing weak, dark speckling; ventral portion of lores and supralabials darkened; dark postorbital stripe extends to ear opening; occipital region bordered by a narrow, dark, W-shaped band; thin dark band on nape; nape and seven regularly shaped dorsal body bands bear bold posterior and diffuse anterior borders; one postsacral band; all bands bordered posteriorly by white tubercles; no distinct dark markings in dorsal interspaces; clusters of enlarged, white scales in ventrolateral folds; light caudal bands do not encircle tail, five remaining bands on original portion of tail; six dark caudal bands remaining on original portion of tail that are wider than light caudal bands; forelimbs generally unicolor; hind limbs bearing faint, broken bands; all ventral surfaces generally beige except for posterior portion of tail that is darkly mottled.

Variation ( Figs. 2 , 3 ). The paratypes vary modestly from the holotype in aspects of color pattern. LSUHC 13946 and 13951–52 have a more faded and less boldly marked dorsal pattern whereas that of LSUHC 13949–50 have an equally bold color pattern but the dorsal body bands are more zig-zag in shape. LSUHC 13938 is unique in having a very boldly marked color pattern bearing irregularly shaped, broken, and medially divided dorsal bands. The ground color of LSUHC 13948 and 13950 is more yellow than that of the remaining type series. LSUHC 13949 and 13951 have unicolored regenerated tails and the tail tips of LSUHC 13946 and 13950 are regenerated. Hatchlings have a far less bold color pattern but more distinct and better-defined black and white caudal bands. Meristic variation is presented in Table 5.

Distribution. Cyrtodactylus aunglini sp. nov. is known only from the type locality of Kyauk Nagar Cave, 11 km southwest of Pyin Oo Lwin, Pyin Oo Lwin Township, Pyin Oo Lwin District, Mandalay Region, Myanmar ( Fig. 1 ).

Etymology. This species is named to honor Mr. Aung Lin of Fauna & Flora International, Yangon for his extensive participation and assistance during all our expeditions in Myanmar and for his outreach projects to various communities that emphasize habitat conservation through sustainable utilization.

Natural History. Kyauk Nagar Cave at 715 m in elevation in disturbed hill forest, lies on the outskirts of the small village of Taung Kyun at approximately 900 m. The 2.5 km of terrane between the village and the cave is composed of scattered karst boulders but at the cave, the boulders are much larger, more numerous, and concentrated around the cave entrance ( Fig. 3 ). The interior of the cave varies from narrow 1 m wide choke points to being 20 m in height and 30 m in width. It bears all the associated cave architecture of stalactites, stalagmites, alcoves, cracks, etc. that provide excellent microhabitat for Cyrtodactylus and it extends for approximately 1.5 km. However, we found no geckos inside the cave but they were concentrated just outside the cave entrance and other nearby subterranean retreats. We saw several hatchlings and all were only in the leaf-litter whereas all the adults were on the karst. The adults were fast, extremely wary, and would escape into cracks between the rocks or into rock piles. Some would escape into cracks between the rock and the ground. All adults were observed near areas into which they could quickly escape and none were seen out in the open on the surface of the boulders. This is a pattern we are beginning to see in several of the karst-associated species we have described ( Grismer et al. 2018a, 2018b, c). These geckos will use caves opportunistically but they are not necessarily cave-adapted. Their concentration around the cave opening at Kyauk Nagar may be related to the fact that this is where the best habitat is in terms of rock size. All observations were made between 1830 and 2400 hrs.

Comparisons. Cyrtodactylus aunglini sp. nov. is most closely related to C. gansi from which it differs by being larger (maximum SVL = 81.6 mm versus 62.3 mm); having well-developed dorsal tubercles that do not extend beyond the hemipenial swelling; distinctive ventrolateral folds; more ventral scales (41–47 versus 30–36); relatively longer digits; more subdigital lamellae (19–23 versus 10); no precloacal groove; 12 or 13 contiguous, pore-bearing, precloacal scales versus 16–29 contiguous, pore-bearing, precloacal scales; enlarged post precloacal scales; and various aspects of head color pattern ( Tables 3, 4, 5). The two are also separated by a 16.9% uncorrected pairwise sequence divergence. From the superficially similar C. mandalayensis , C. aunglini sp. nov. varies by having more longitudinal rows of body tubercles (21–26 versus 18); more ventral scales (41–47 versus 32); more pore-bearing, precloacal scales (12 or 13 versus eight); caudal scales arranged in regular segments; and various aspects of color pattern ( Tables 3, 4, 5). Cyrtodactylus aunglini sp. nov. varies from all other species of the gansi group in not having well-developed tubercles that extend beyond the base of the hemipenial swellings; it varies from all other species of the gansi group except C. myaleiktaung sp. nov. in that the top of the head is unicolor as opposed to bearing a dark pattern of varying configurations ( Table 3, 4, 5). Table 3 lists combinations of other characters separating C. aunglini sp. nov. from varying combinations of other species of the gansi group.

Figures

FIGURE 1. Maximum likelihood consensus tree topology of the Cyrtodactylus gansi group with BPP and UFB support values, respectively, at the nodes. Distribution of the species of the C. gansi group in India and Myanmar.

FIGURE 2. Cyrtodactylus aunglini sp. nov. from from Kyauk Nagar Cave, 11 km southwest of Pyin Oo Lwin, Pyin Oo Lwin Township, Pyin Oo Lwin District, Mandalay Region, Myanmar (20.93087°N, 95.22580°E; 715 m in elevation). A. Adult male paratype 13948. B. Adult male paratype 13950. C. Adult male holotype 13947. D. Hatchling LSUHC 13945.

FIGURE 3. A. Cyrtodactylus aunglini sp. nov. from from Kyauk Nagar Cave, 11 km southwest of Pyin Oo Lwin, Pyin Oo Lwin Township, Pyin Oo Lwin District, Mandalay Region, Myanmar (20.93087°N, 95.22580°E; 715 m in elevation) from left to right adult male paratypes LSUHC 13946, 13950, 13948; adult male holotype LSUHC 13947, adult male paratypes 13949, 13951–52. B. Entrance to Kyauk Nagar Cave. C. Karst microhabitat and leaf-litter near the cave.