Thursday, January 14, 2021

[Herpetology • 2021] Cyrtodactylus chungi • A New Cyrtodactylus (Squamata: Gekkonidae) from Binh Thuan Province, southern Vietnam


Cyrtodactylus chungi 
Ostrowski, Le, Ngo, Pham, Phung, Nguyen & Ziegler, 2021

 Chung’s Bent-toed Gecko | Thạch sùng ngón chứng || DOI: 10.5852/ejt.2021.731.1203

ABSTRACT
We describe a new species of Cyrtodactylus on the basis of two specimens collected from Ta Kou Nature Reserve, Binh Thuan Province, southern Vietnam. Cyrtodactylus chungi sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by a combination of the following characters: relatively small body size (SVL up to 68.5 mm); a continuous neckband; 5 or 6 irregular transverse dorsal bands; 11 or 12 bands on original tail; keeled tubercles present on dorsum, posterior limbs and tail; 17 or 18 irregular dorsal tubercle rows; 30 or 31 ventral scale rows; ventrolateral skin folds indistinct; an angular series of seven precloacal pores in male and six pitted, enlarged precloacal scales in female, each series separated by a diastema of undifferentiated scales from 4–6 enlarged, poreless femoral scales; median subcaudals slightly enlarged; 17–20 subdigital lamellae under the fourth toe. Based on molecular analyses of the fragment of mitochondrial gene cytochrome c oxidase subunit I (COI), the new species is recovered as the sister taxon to Cyrtodactylus cattienensis s. str. with a genetic divergence of more than 9%. In phylogenetic analyses, the new species is recovered as a member of the Cyrtodactylus irregularis species group.

Keywords: Cyrtodactylus chungi sp. nov., molecular phylogeny, taxonomy, Ta Kou Mountain, COI gene


Class Reptilia Laurenti, 1768
Order Squamata Oppel, 1811

Family Gekkonidae Gray, 1825
Subfamily Gekkoninae Gray, 1825

Genus Cyrtodactylus Gray, 1827

Fig. 3. Cyrtodactylus chungi sp. nov. in life.
Top: holotype, ♂ (IEBR 4581). Bottom: paratype, ♀ (IEBR 4582).
Photos T.M. Phung.

Fig. 4. Cyrtodactylus chungi sp. nov., in life paratype, ♀ (IEBR 4582).
Photos T.M. Phung.


Cyrtodactylus chungi sp. nov.

Diagnosis: The new species can be distinguished from other members of the genus Cyrtodactylus by a combination of the following characters (Table 1): relatively small body size (SVL up to 68.5 mm); a continuous neckband; 5 or 6 irregular transverse dorsal bands; 11 or 12 bands on original tail; keeled tubercles present on dorsum, posterior limbs and tail; 17 or 18 irregular dorsal tubercle rows; 30 or 31 ventral scale rows; ventrolateral skin folds indistinct; an angular series of seven precloacal pores in male and six pitted, enlarged precloacal scales in female, each series separated by a diastema of undifferentiated scales from 4–6 enlarged, poreless femoral scales; median subcaudals slightly enlarged; 17–20 subdigital lamellae under the fourth toe.

Etymology: Specific epithet ‘chungi’ is in honor of Prof. Dr Ngo Dac Chung, College of Education, Hue University, in recognition of his outstanding contributions to training of many herpetologist generations from Hue University. For the common names we suggest Chung’s Bent-toed Gecko (English) and Thạch sùng ngón chứng (Vietnamese).

Distribution: Cyrtodactylus chungi sp. nov.is currently known only from the type locality in Ta Kou Nature Reserve, Binh Thuan Province, Vietnam. 

Fig. 9. Habitat of Cyrtodactylus chungi sp.nov. in Ta Kou Nature Reserve, Binh Thuan Province.
Photo C.T. Pham.



Sabrina Ostrowski, Minh Duc Le, Hanh Thi Ngo, Cuong The Pham, Trung My Phung, Truong Quang Nguyen and Thomas Ziegler. 2021. A New Cyrtodactylus (Squamata: Gekkonidae) from Binh Thuan Province, southern Vietnam. European Journal of Taxonomy. 731(1), 47-70. DOI: 10.5852/ejt.2021.731.1203