Hemiphyllodactylus ngwelwini, Grismer & Wood & Quah & Thura & Oaks & Lin, 2020

Grismer, L. Lee, Wood, Perry L., Quah, Evan S. H., Thura, Myint Kyaw, Oaks, Jamie R. & Lin, Aung, 2020, Four new Burmese species of Hemiphyllodactylus Bleeker (Squamata: Gekkonidae) from distantly related parapatric clades from the Shan Plateau and Salween Basin, Zootaxa 4758 (1), pp. 45-82 : 57-63

publication ID	https://doi.org/ 10.11646/zootaxa.4758.1.2
publication LSID	lsid:zoobank.org:pub:B0558D50-BF71-4C1B-BDA8-81FDB46109F9
DOI	https://doi.org/10.5281/zenodo.3812887
persistent identifier	https://treatment.plazi.org/id/03A38792-FF82-FFCB-F5F3-FC38FEE7FC9D
treatment provided by	Plazi
scientific name	Hemiphyllodactylus ngwelwini
status	sp. nov.

Treatment

Hemiphyllodactylus ngwelwini sp. nov.

Ngwe Lwin’s Slender Gecko

( Figs. 4 View FIGURE 4 , 5 View FIGURE 5 )

Holotype. Adult male ( LSUHC 14473 View Materials ) collected on 2 August 2019 at 1955 hrs by L. Lee Grismer, Perry L. Wood Jr., Myint Kyaw Thura, and Aung Lin at the Thayeumin Cave , State, Myanmar (20.72288°N 96.58994°E WGS; 1057 m in elevation). GoogleMaps

Paratypes. Females and juvenile LSUHC 14474–76 View Materials bear the same collection data as the holotype. Females LSUHC 14328–29 View Materials and male 14330 were collected from Pwe Hla Village , Shan State (20.84125°N 96.69030°E WGS; 1416 m in elevation) by L. Lee Grismer, Perry L. Wood, Jr, Evan S. H. Quah, Myint Kyaw Thura, Jamie R. Oaks, and Aung Lin on 14 November 2018 GoogleMaps and female LSUHC 14489 View Materials bears the same collecting locality but was collected by L. Lee Grismer, Perry L. Wood Jr., Myint Kyaw Thura, and Aung Lin on 3 August 2019 . Female LSUHC 14326 View Materials and male 14327 from the Myintmahati Cave , Shan State (20.59082°N 96.61198°E WGS; 1326 m in elevation) were collected by L. Lee Grismer, Perry L. Wood, Jr, Evan S. H. Quah, Myint Kyaw Thura, Jamie R. Oaks, and Aung Lin on 15 November 2018 GoogleMaps .

Diagnosis. Hemiphyllodactylus ngwelwini sp. nov. can be separated from all other species of Hemiphyllodactylus by possessing the unique combination of having a maximum SVL of 40.2 mm; 9–13 chin scales; enlarged postmentals; five circumnasal scales; 1–3 intersupranasals (=postrostrals); 8–11 supralabials; 8–10 infralabials; 11–14 longitudinally arranged dorsal scales at midbody contained within one eye diameter and seven or eight ventral scales; four subdigital lamellae on the first finger and toe; 15–22 continuous, pore-bearing, femoroprecloacal scales in males; no plate-like subcaudal scales; adult females variably yellow; a dark postorbital stripe extending to at least base of neck; dorsolateral light-colored spots usually present on trunk; no dark, dorsolateral or ventrolateral stripe on trunk; dark zig-zag of paravertebral markings on trunk variable; light-colored postsacral marking variably bearing anteriorly projecting arms; and caecum and gonads unpigmented. These characters are scored across all Burmese species in Tables 3 and 6 and from all other species of Hemiphyllodactylus from southern China and western Thailand (clades 3 and 4 in Grismer et al. (2017: Table 3)).

Description of holotype. Adult male, SVL 34.4 mm; head triangular in dorsal profile, depressed, distinct from neck; lores flat; rostrum moderate in length (SN/SVL 0.10); prefrontal region weakly concave; canthus rostralis smoothly rounded, barely discernible; snout moderate, rounded in dorsal profile; eye large; ear opening elliptical, small; eye to ear distance greater than diameter of eye; rostral wider than high, bordered posteriorly by large supra- nasals; two differently sized intersupranasals (=postnasals); external nares bordered anteriorly by rostral, dorsally by supranasal, posteriorly by two postnasals, ventrally by first supralabial (=circumnasals); eight (R, L) rectangular supralabials tapering to below posterior margin of eye; 9, 10 (R, L) rectangular infralabials tapering to below posterior margin of eye; scales of rostrum, lores, top of head, and occiput small, granular, those of rostrum largest and slightly raised; dorsal superciliaries flat, mostly square, subimbricate, largest anteriorly; mental triangular, bordered laterally by first infralabials, posteriorly by two large nearly square postmentals; each postmental in contact with first infralabial, bordered laterally by single slightly enlarged sublabial; 10 chin scales; gular scales small, subimbricate, grading posteriorly into slightly larger, subimbricate throat and even larger pectoral scales which grade into slightly larger, subimbricate ventrals.

Body somewhat elongate (AG/SVL 0.49), dorsoventrally compressed; ventrolateral folds absent; dorsal scales small, granular, 12 dorsal scales at midbody contained within one eye diameter; ventral scales flat, subimbricate much larger than dorsal scales, eight ventral scales contained within one eye diameter; precloacal scales slightly larger than abdominal scales; pore-bearing precloacal scales continuous with pore-bearing femoral scales, totaling 21 pore-bearing femoroprecloacal scales; single enlarged tubercle on anterior margin of hemipenial swelling; forelimbs short, robust in stature, covered with flat, subimbricate scales dorsally and ventrally; palmar scales flat, subimbricate; all digits except digit I well-developed; digit I vestigial, clawless; distal subdigital lamellae of digits II–V undivided, angular and U-shaped, lamellae proximal to these transversely expanded; distal lamellar formula of digits II–V 3-3-3-3 (R, L); four transversely expanded lamellae on digit I; claws on digits II–V well developed, unsheathed; distal portions of digits strongly curved, terminal joint free, arising from central portion of lamellar pad; hind limbs short, more robust than forelimbs, covered with flat, juxtaposed scales dorsally and larger, flat subimbricate scales ventrally; plantar scales low, flat, subimbricate; all digits except digit I well-developed; digit I vestigial, clawless; distal subdigital lamellae of digits II–V undivided, angular and U-shaped, lamellae proximal to these transversely expanded; distal lamellar formula of digits II–V 3-3-3-3 (R, L); four transversely expanded lamellae on digit I; claws on digits II–V well-developed, unsheathed; distal portions of digits strongly curved, terminal joint free, arising from central portion of lamellar pad; caudal scales not occurring in whorls; dorsal caudal scales of original tail larger than dorsal body scales, flat, subcycloid, subimbricate; subcaudals slightly larger than dorsal caudals, not plate-like. Raw and ratiometric mensural data are presented in Table 7.

Coloration in life ( Fig. 4 View FIGURE 4 ). All Hemiphyllodactylus are capable of considerable change in the intensity and boldness of their coloration and pattern. The description below was taken when the holotype was photographed the morning after capture, approximately 12 hours following the time of collection while during its light-phase. Ground color of top of head, body, and limbs, gray and densely mottled with darker markings; top of head overlain with dark, semi-reticulate pattern; broad, dark, diffuse pre- and postorbital stripe extends from the external nares, through eye to just posterior of forelimb insertion on the body; pairs of diffuse, dark, paravertebral markings counter-shaded posteriorly with diffuse white spots extend from nape to base of tail transforming into a distinct, dark (nearly black), post-sacral band; immaculate, beige post-sacral marking immediately posterior to black post-sacral band not bearing light-colored, anteriorly projecting arms; dorsum and flanks faintly mottled with diffuse speckling; limbs bearing irregularly shaped, diffuse, dark markings; original tail bearing eight dark bands; gular region generally immaculate, except for darker lateral areas and faint stippling in scales; pigmentation density increases posteriorly with abdomen being generally gray; ground color of dorsal caudal region beige, bearing nine black diffuse bands not encircling tail; median subcaudal region faintly orange, generally immaculate.

Variation ( Figs. 4 View FIGURE 4 , 5 View FIGURE 5 ). The color patterns of the paratypes generally match that of the holotype and no interpopulational differences were observed ( Table 6). The dark, dorsal pattern of LSUHC 14326, 14328, 14330, 14489 is not as bold as that of the holotype. LSUHC 14476 is a juvenile with a broken tail. The tails of LSUHC 14326–28, 14330, and 14489 are regenerated and generally unicolor gray. Variation in scales counts, mensural data, and additional minor aspects in coloration are presented in Table 7.

Distribution. Hemiphyllodactylus ngwelwini sp. nov. is known from three localities across a distance of approximately 29 km from Pwe Hla Village in the north to the Thayeumin and Myintmahati caves in the south, Shan State ( Fig. 1 View FIGURE 1 ).

Natural History. All individuals from Pwe Hla Village were found on man-made structures in highly disturbed forest. LSUHC 14328–29 and LSUHC 14489 were collected on the walls of cement water tanks and LSUHC 14330 was collected from the underside of a wooden roof from a nearby rest shelter along the road. Both specimens from the Myintmahati Cave population (LSUHC 14326–27) were collected on cement structures immediately outside of a limestone cave in highly disturbed forest. LSUHC 14473 (the holotype) and LSUHC 14474–76 from the Thayeumin Cave population were found outside the limestone cave on corrugated tin shacks, cement buildings, and other man-made structures ( Fig. 6 View FIGURE 6 ) between a rice paddy and an isolated tract of highly disturbed forest.

Etymology. The specific epithet recognizes and honors Mr. Ngwe Lwin, northern Program Manager of Fauna and Flora International in Myanmar. Mr. Ngwe Lwin has been supportive and invaluably instrumental in facilitating our field work in Myanmar since October of 2017.

Comparisons. The molecular analyses indicate that Hemiphyllodactylus ngwelwini sp. nov. is a genetically distinct member of the north lineage composed of three, putatively, interbreeding populations being that the intrapopulational uncorrected pairwise sequence divergence across 29 km is only 1.0% and that individuals from the three populations are polyphyletic with respect to one another ( Fig. 1 View FIGURE 1 , Table 8). Hemiphyllodactylus ngwelwini sp. nov. is the sister species to a clade composed of H. ywanganensis and the sister species H. uga , and H. linnwayensis ( Fig. 1 View FIGURE 1 ) from which it bears an uncorrected pairwise sequence divergence of 8.4% from H. linnwayensis , 9.0% from H. uga , and 8.5% from H. ywanganensis ( Table 8). H. ngwelwini sp. nov. differs significantly from H. linnwayensis , H. montawaensis , and H. tonywhitteni in mean values of CS (10.8 vs 5.0, p = 7.42 -06; 10.8 vs 6.3, p = 4.93 -05; and 10.8 vs. 6.6, p = 5.14 -05; respectively; Table 3); differs significantly from H. tonywhitteni in mean values of DS (12.7 vs 14.8, p = 0.014; Table 3); and from H. montawaensis it differs significantly in adjusted mean values of HL (1.985 vs 2.852, p = 0.021; Fig. 2 View FIGURE 2 , Table 3). Hemiphyllodactylus ngwelwini sp. nov. differs from H. uga and H. ywanganensis (n = 2) by having four subdigital lamelae on the first finger as opposed to two or three in H. uga and three in H. ywanganensis and four subdigital lamelae on the first toe as opposed to two or three in the latter two species. However, the sample sizes of the latter two species (n =4 and n = 2, respectively) are so small that these values are likely to change with the addition of more samples. Owing to the high intraspecific variability of color pattern characters in H. ngwelwini sp. nov. ( Figs. 4 View FIGURE 4 , 5 View FIGURE 5 ), no interspecific differences between it and other members of the north lineage were found.