in Chomdej, Pradit, Suwannapoom, ... et Gong, 2021.
Cyrtodactylus species are the most diverse of the geckos and are widely distributed in Southeast Asia, including Thailand. However, their patterns of distribution, especially in northern and western parts of Thailand, remain unknown because few Cyrtodactylus species in these regions have been described. Thus, a data set of mitochondrial NADH dehydrogenase 2 (ND2) gene and flanking tRNAs from Cyrtodactylus found in northern and western Thailand, including contiguous areas, was assembled to elucidate phylogenetic relationships and identify the distribution patterns of these geckos. The results showed four well-supported clades, a northwestern clade (A), a northern clade (B), a western clade (C), and a special clade characterized by specific morphological features (D). Clades A–C were grouped with strong support by the geography of their localities from northern Thailand (Mae Hong Son and Chiang Mai Provinces) along the Tenasserim mountain ranges to Phang-Nga Province, Thailand. Clade D is a distinct clade of Cyrtodactylus species characterized by a tuberculate and prehensile tail and distributed widely in mainland Southeast Asia. Overall, the results suggest a pattern of geographic separation and distribution of Cyrtodactylus in northern and western Thailand. Additionally, this study provides evidence of a hidden biodiversity of Cyrtodactylus in these regions.
The phylogeny presented in this study illustrates the relationship and distribution of Cyrtodactylus species in northern and western Thailand. Four clades of Cyrtodactylus were recovered: a northwestern clade (clade A), a northern clade (clade B), a western clade (clade C), and a special clade (clade D). Clade A distributed from the Salween Basin in Myanmar to the Thanon Thong Chai mountain range in northern Thailand and was grouped with the “sinyineensis group”. Clade B was found to disperse in major mountain ranges of northern Thailand, including the Thanon Thong Chai, Daen Lao, and Khun Tan ranges. Clade C radiated along the Tenasserim Range from Kanchanaburi Province to Phang-Nga Province. Clade D was unique among the four clades in that Cyrtodactylus in this clade were grouped based on their tuberculate and prehensile tails, and were distributed widely in mainland Southeast Asia. The present phylogeny will be a useful guide for the identification or description of many unknown Cyrtodactylus species, especially from northern and western Thailand. The results also raise the possibility of analysis of other aspects of Cyrtodactylus species, such as their evolution, ecomorphology, and phylogenetic endemism. Finally, this study implies a hidden biodiversity of Cyrtodactylus in northern and western Thailand.
Siriwadee Chomdej, Waranee Pradit, Chatmongkon Suwannapoom, Parinya Pawangkhanant, Korakot Nganvongpanit, Nikolay A. Poyarkov, Jing Che, Yangchun Gao and Shiping Gong. 2021. Phylogenetic Analyses of Distantly Related Clades of Bent-toed Geckos (Genus Cyrtodactylus) reveal An Unprecedented Amount of Cryptic Diversity in northern and western Thailand. Scientific Reports. 11: 2328. DOI: 10.1038/s41598-020-70640-8