Tuesday, April 14, 2020

[Herpetology • 2020] Cyrtodactylus phnomchiensis • A New Species of Cyrtodactylus (Squamata, Gekkonidae) from Cambodia’s Prey Lang Wildlife Sanctuary


Cyrtodactylus phnomchiensis
Neang, Henson & Stuart, 2020


Abstract
Cyrtodactylus phnomchiensis sp. nov. is described from Phnom Chi, an isolated mountain in Prey Lang Wildlife Sanctuary, Kampong Thom Province, Cambodia. The new species is recognized by having a unique combination of morphological characters, including snout-vent length 76.1–80.7 mm; paravertebral tubercles 31–36; ventral scales 45–54; enlarged femoral scales 0–8, without pores; enlarged precloacal scales 7–10, bearing pores 4–5 in males, pits 1–7 in females; the posterior border of nuchal loop unbroken and pointed, bordered anteriorly and posteriorly by a broad yellow or yellowish white band; and yellow spots on top of head. The new species also represents a divergent mitochondrial DNA lineage within the C. irregularis complex that is closely related to C. ziegleri, but the phylogenetic relationships among the new species and two divergent mitochondrial subclades within C. ziegleri are not resolved based on available sequence data. Cyrtodactylus phnomchiensis sp. nov. is the only member of the C. irregularis complex known to occur west of the Mekong River. The new species may be endemic to Phnom Chi, and likely faces imminent conservation threats.

Keywords: Cyrtodactylus irregularis, C. ziegleri, Mekong River, Phnom Chi, Sphenomorphus preylangensis



Figure 3. Cyrtodactylus phnomchiensis sp. nov. in life.
 A Male holotype CBC 03012 and B female paratype CBC 03013.

Cyrtodactylus phnomchiensis sp. nov.

Etymology: The specific epithet is taken from the type locality of Phnom Chi and the Latin suffix -ensis meaning “originating from.” The specific epithet is masculine in agreement with the gender of Cyrtodactylus.

Diagnosis: Cyrtodactylus phnomchiensis sp. nov. is distinguished from the 19 other named species in the C. irregularis group (Ngo and Chan 2010; Nguyen et al. 2013, 2017; Pauwels et al. 2018) by having the combination of SVL 76.1–80.7 mm; relatively long body, AG/SVL 0.451–0.481; relatively long tibia, CrusL/SVL 0.172–0.200; subdigital lamellae on fourth finger 18–20; subdigital lamellae on fourth toe 20–23; longitudinal dorsal rows of tubercles 18–20; paravertebral rows of tubercles 31–36; ventral scales 45–54; enlarged femoral scales 0–8, without pores; enlarged precloacal scales 7–10, bearing pores 4 or 5 in males, pits 1–7 in females; precloacal groove absent; median row of transverse subcaudal scales only slightly enlarged; posterior border of nuchal loop unbroken and pointed, bordered anteriorly and posteriorly by broad yellow or yellowish white band; dark brown body bands 3 or 4, the first intact, the second, third and fourth more irregular, alternating with two or three yellowish white or light brown body bands, about half the width of dark brown body bands; and yellow spots on top of head.

Figure 7. Habitat at Phnom Chi, the type locality of Cyrtodactylus phnomchiensis sp. nov.

Distribution and natural history: The new species is known only from the type locality at Phnom Chi in Prey Lang Wildlife Sanctuary, Kampong Thom Province, Sandan District, Cambodia. All individuals were found at night between 2001–2147 hr in evergreen-large dipterocarp dominated forest associated with rocky terrain (Fig. 7). The holotype CBC 03012 was found on a rock face following evening rain, paratypes CBC 03013–14 were on boulders following evening rain, paratype CBC 03003 was on leaf litter along a forest trail, and paratype CBC 03004 was on a rock wall at the entrance to a cave. Only five individuals were found during five-survey nights, suggesting the species is relatively uncommon. None were encountered during a brief survey by NT in the wet season of 2014 (Hayes et al. 2015). The new species is the only member of the C. irregularis complex known to occur west of the Mekong River (Nguyen et al. 2017; Pauwels et al. 2018).


Thy Neang, Adam Henson and Bryan L. Stuart. 2020. A New Species of Cyrtodactylus (Squamata, Gekkonidae) from Cambodia’s Prey Lang Wildlife Sanctuary. ZooKeys. 926: 133-158. DOI: 10.3897/zookeys.926.48671