Friday, September 29, 2023

[Herpetology • 2018] Cyrtodactylus thathomensis • A New Karst-dwelling Bent-toed Gecko (Squamata: Gekkonidae) from Xiangkhoang Province, northeastern Laos

Cyrtodactylus thathomensis 
 Nazarov, Pauwels, Konstantinov, Chulisov, Orlov & Poyarkov, 2018

We describe a new karst-dwelling Cyrtodactylus from Ban Thathom, Xiangkhoang Province, northeastern Laos. The new species can be distinguished from other congeners by having four dark dorsal bands between limb insertions, a discontinuous nuchal loop, 10 precloacal pores in males or 10–12 precloacal pits (females) separated by a diastema from a series of enlarged femoral scales bearing 18 or 19 pores (male) or 8–10 pits (females) along each femur, 14–18 dorsal tubercle rows at midbody, no precloacal groove, 30–36 midbody scale rows across belly between ventrolateral skin folds, transversely enlarged subcaudal plates, and a maximal known snout-vent length of 75.5 mm. Our description brings to 22 the number of Cyrtodactylus species recorded from Laos.

Keywords: Indochinese region, Karst, Limestone, Herpetology, Taxonomy,  New species

Male holotype of Cyrtodactylus thathomensis sp. nov. (ZMMU R-14919)
A: General view of holotype in situ; B: Precloacal region with row of femoral and precloacal pores separated by diastema; C: Postcloacal spurs (see arrow); D: Lateral side of the head with supralabials and infralabials scalation; E: Ventral surface of the head with mental scalation; F: Dorsum surface with the rows of enlarged tubercles.
Photos by E.L. Konstantinov (A) and R.A. Nazarov (B–F).

 Live female paratype of Cyrtodactylus thathomensis sp. nov. (ZISP 29731) in dorsal view
(Photo by E.L. Konstantinov)

Cyrtodactylus thathomensis sp. nov. 

Diagnosis: Cyrtodactylus thathomensis sp. nov. can be distinguished from all other congeneric species by its medium body size (maximal known SVL 75.5 mm); dorsal tubercles in 14–18 rows at midbody; midbody scale rows 30–36 across belly between ventrolateral skin folds; a continuous series of 10–12 pore-bearing (male) or pitted (females), enlarged precloacal scales, separated by a diastema from a series of enlarged femoral scales bearing 18 or 19 pores (male) or 1–9 pits (females) on each femur; absence of precloacal groove; transversely enlarged median subcaudal scales; and four dark dorsal bands between limb insertions.

Etymology: The specific epithet “thathomensis” is a Latinized toponymic adjective, referring to the type locality of the new species, Ban Tha-Thom. We suggest the following common names: Ki Chiem Thathom (Lao), Tuk Khai Thathom (Thai), Thathom Bent-toed Gecko (English), Tatomskiy Krivopalyi Gekkon (Russian), Thathomkromvingergekko (Dutch), and Cyrtodactyle de Thathom (French).

Roman A. Nazarov, Olivier S.G. Pauwels, Evgeniy L. Konstantinov, Anatoliy S. Chulisov, Nikolai L. Orlov, Nikolay A. Poyarkov, Jr. 2018. A New Karst-dwelling Bent-toed Gecko (Squamata: Gekkonidae: Cyrtodactylus) from Xiangkhoang Province, northeastern Laos. Zoological Research. 39(3); 202-219. DOI: 10.24272/j.issn.2095-8137.2018.010