The discovery of two new species in the Cyrtodactylus irregularis group highlights that hidden diversity remains in the largest clade of the mega-diverse genus Cyrtodactylus

Abstract

The Cyrtodactylus irregularis group, originally considered to consist of only one taxon, has been split into 26 species. We herein present the distribution of all species within the group in Cambodia, Laos and Vietnam and describe two new species based on integrative analyses. Cyrtodactylus chumuensis sp. nov. is discovered from Dak Lak Province and distinguished from the remaining taxa by more than 11.86% genetic divergence and by the following distinct morphological characters: size medium (SVL 67.5 mm); enlarged femoral scales on each thigh 4–5, femoral pores 0–2 in males; precloacal pores 6–7 in males; ventral scale rows 43–45; lamellae under toe IV 17–21. Cyrtodactylus arndti sp. nov. is described from Binh Dinh Province and genetically differentiated from its congeners by a minimum of 11.42% and by the following characters: adult size medium (SVL 73.4–80.8 mm); enlarged femoral scales on each thigh 5–11; femoral pores 0–2 in males; 6 precloacal pores in males, females with 6 pitted precloacal pores; ventral scale rows 26–38; lamellae under toe IV 17–22; subcaudal scales transversely enlarged. Additionally, we highlight the potential cryptic diversity with the taxon currently regarded as C. pseudoquadrivirgatus and understudied areas in Vietnam where new species will likely be discovered.