Ptychozoon popaense, Grismer & Wood & Thura & Grismer & Brown & Stuart, 2018

Grismer, L. Lee, Wood, Perry L., Thura, Myint Kyaw, Grismer, Marta S., Brown, Rafe M. & Stuart, Bryan L., 2018, Geographically structured genetic variation in Ptychozoon lionotum (Squamata: Gekkonidae) and a new species from an isolated volcano in Myanmar, Zootaxa 4514 (2), pp. 202-214 : 208-211

Ptychozoon popaense sp. nov.

Mt. Popa Parachute Gecko

Fig. 2

Holotype. LSUHC 13508 , adult male, collected by Myint Kyaw Thura on 27 May 2017 from Yay Su camp, 16 km northeast of Kyauk-pa-taung Town , Kyauk-pa-taung Township, Mt. Popa, Mandalay Region, Myanmar (20.88331°N, 95.26638°E, 629 m above sea level).

Paratopotype. Adult female LSUHC 13507 bears the same collection data as the holotype.

Diagnosis. Ptychozoon popaense s p. nov. can be differentiated from all other species of Ptychozoon based on having the unique combination of separated supranasals; presence of an infra-auricular flap; dorsal and caudal tubercles absent; 32–36 enlarged ventral scales; enlarged femorals absent; 21 enlarged, pore-bearing precloacals in the male and 12 dimpled precloacal scales in the female; 13 or 14 transversely enlarged subdigital lamellae under the fourth toe; 28 or 29 scales across the caudal flap; distal caudal lobes not fused into a long caudal flap; bases of 15–19 lobes fused anterior to the caudal flap; caudal lobes angling slightly posteriorly; thick, dark, postorbital stripe present; four dark, dorsal, body bands between limb insertions; irregularly shaped, with white, vertebral markings; and adults not having distinct immaculate black and white caudal bands dorsally ( Table 4).

Description of holotype. Adult male SVL 86.2 mm; head short (HL/SVL 0.26), wide (HW/SVL 0.20), depressed (HD/HL 0.43), distinct from neck; snout rounded at tip in dorsal profile; interorbital region flat; lores rounded; rostral scale large, rectangular, without dorsomedial groove, in contact posteriorly with two supranasals, one postnasal, and laterally with nostrils and first supralabials; supralabials (9R,10L), supralabial eight in midorbital position; infralabials (9R,10L); nostrils elliptical with long axis oriented dorsoventrally, occupying anterior portion of nasal scale, bordered anteriorly by rostral, dorsally by supranasal, posteriorly by four postnasals of varying sizes, and ventrally by first supralabial; scales on rostrum granular slightly larger than granular scales on top of head and occiput; no ridge of tubercles along mandibles; eyes large (ED/HL 0.24), less than snout length and EAO distance; pupil vertically elliptical, crenelated; supraciliaries elongate, posteriormost spinose; auricular opening rounded, lacking enlarged lobes; tympanum deeply sunk; infra-auricular flap broad, rounded, extending from below corner of mouth to base of neck, measuring 3.5 mm at its widest point; dorsal scales of infra-auricular flap large, subimbricate proximally, small juxtaposed distally, minute and granular ventrally; infra-auricular flap on right side deeply notched; mental triangular, wider than deep, bordered laterally by first infralabials and posteriorly by paired, rectangular postmentals contacting medially for 70% of their length; one row of enlarged sublabials bordering infralabials, anteriormost largest; gular scales small, rounded, grading abruptly into larger imbricating throat and ventral scales.

Body dorsoventrally depressed, relatively stout (AG/SVL 0.47); axilla-groin cutaneous expansion (flap) 5.5 mm at midpoint of body and bearing enlarged, juxtaposed, rectangular scales dorsally and minute, juxtaposed, subrectangular scales ventrally; dorsal body scales minute, flat, rounded, juxtaposed, largest mid-dorsally; 36 transverse rows of large, smooth, flat, subimbricate ventrals, ventrals much larger than dorsals, decreasing in size laterally; 21 elevated, enlarged, pore-bearing, precloacal scales; seven rows of enlarged, post-precloacal scales; scales immediately anterior to vent granular.

Limbs short, robust (FL/SVL 0.11; TBL/SVL 0.16); dorsal scales of forelimbs, flat, juxtaposed, slightly larger than dorsal body scales and juxtaposed ventral forelimb scales; anterior and posterior margins of forelimbs, posterior margins of hind limbs, and anterior margins of forelegs bearing wide, cutaneous flaps extending to bases of digits I and V, bearing subimbricate, moderately larger scales dorsally and smaller imbricate scales ventrally wide; wide predigital notch in preantebrachial flap; palmar scales smooth, rounded; digits fully webbed, relatively short, dorsoventrally compressed; undivided transverse subdigital lamellae number 12 (I), 12 (II), 15 (III), 15 (IV), 12 (V), distalmost lamellae V-shaped; claws arise from within the dorsal surface of digital pads; first digit lacks a claw; dorsal scales of hind limbs, flat, juxtaposed, smaller than dorsal body scales and flat, subimbricate scales of thigh; posterior margins of thigh and foreleg, and anterior margin of foreleg have wide, cutaneous flaps bearing subimbricate, moderately large scales dorsally and much smaller subimbricate scales ventrally; pretibial flap not contacting base of digit V; post-tibial flap contacts base of digit I; plantar scales smooth, subimbricate; digits fully webbed; transverse subdigital lamellae number 11 (I), 13 (II), 15 (III), 13 (IV), 14 (V), distalmost lamellae Vshaped; claws arise from within the dorsal surface of digital pads; and first digit lacks a claw.

Tail original, flattened, moderate in length (TaL/SVL 1.04); two median rows of transversely widened, smooth subcaudals; postcloacal scales on heimpenial swelling large, flat, imbricate; dorsal caudals flat, juxtaposed, larger than dorsal body scales, occurring in whorls; 6–8 smaller scales between larger scales delimiting whorls; tail width and caudal lobes slightly decrease posteriorly; 25 caudal lobes on each side slightly angled posteriorly; 19 lobes fused at their bases, prior to grading posteriorly into short, straight-edged, terminal tail flap terminal tail flap short (8.6 mm), not wider than tail.

Coloration in life ( Fig. 2 ). Dorsal ground color of head, body and limbs light-green, that of tail light-brown; top of head bearing three elongate, grey markings extending onto nape; wide, grey preorbital stripe extends through eye terminating on nape, becoming progressively darker and thicker posteriorly; labials much lighter than ground color of head, bearing thin dark lines; four wide, sinuous, grey bands between limb insertions bearing diffuse anterior margins and black, well-defined posterior margins and extending onto flanks; a series of irregularly shaped, poorly defined, immaculate, white vertebral blotches extending from nape to sacrum; dorsal surface of limbs bearing grey, diffuse, irregularly shaped, banded to reticulate patterns; seven dark caudal bands becoming darker posteriorly separated by six lighter bands, posterior two lightest; terminal flap nearly black; ventral surfaces of head, body, and limbs beige, generally immaculate; subcaudal region distinctly banded. All colors have faded to varying shades of grey in preservative.

Variation. The female paratopotype is nearly identical to the holotype in all aspects of coloration and pattern except that the terminal flap is white as opposed to being nearly black and the original tail was broken off at the time of collection. Meristic differences are presented in Table 5.

Comparisons. Ptychozoon popaense sp. nov. is most closely related to P. lionotum sensu lato but differs from it by having 15–19 fused caudal lobes as opposed to 2–11; lacking as opposed to having a thick, dark, postorbital stripe; and having as opposed to lacking irregularly shaped, white, vertebral markings. From P. bannaense it differs by having 21 as opposed to 17 pore-bearing precloacal scales in males; 13 or 14 as opposed to 16 or 17 enlarged, transverse, subdigital lamellae on the fourth toe; slight as opposed to extreme posteriorly angled caudal lobes; minimal as opposed to extreme reduction in the width of the caudal lobes toward the end of the tail; and having as opposed to lacking irregularly shaped, white, vertebral markings. Combinations of other characters differentiating P. popaense sp. nov. from the other more distantly related species are presented in Table 4.

Distribution. Ptychozoon popaense is know only from the type locality from Yay Su camp, 16 km northeast of Kyauk-pa-taung Town, Kyauk-pa-taung Township, Mt. Popa, Mandalay Region, Myanmar ( Fig. 1 ).

Etymology. The gender of the genus Ptychozoon is neutral, therefore the specific epithet popaense is the adjective used here in reference to the type locality, Mt. Popa, Mandalay Region.

Natural history. The type material was collected in deciduous dipterocap forest ( Fig. 3 ). Both specimens were found on the walls of a small wooden building while foraging for insects during the evening at approximately 1900 hrs.

Figures

FIGURE 1. Left: distribution of the samples of the Ptychozoon lionotum Group used in the molecular phylogenetic analysis. Right: Maximum likelihood consensus tree topology of Ptychozoon. Black dots denote nodes with BPP ¿ 0.95, UFB ¿ 95, and LRT ¿ 0.80. The grey dot denotes a node with BPP ¿ 0.95, UFB ± 95, and LRT ¿ 0.80. The open dot denotes a node with no significant support.

FIGURE 2. Adult male holotype of Ptychozoon popaense sp. nov. (LSUHC 13508) from Yay Su camp, 16 km northeast of Kyauk-pa-taung Town, Kyauk-pa-taung Township, Mt. Popa, Mandalay Region, Myanmar.

FIGURE 3. Deciduous dipterocap forest habitat of Ptychozoon popaense sp. nov. on Mt. Popa, Mandalay Region, Myanmar.