A new Cyrtodactylus species, C. laevissp. nov., from the dry-hot valleys near the Yarlung Zangbo River in Re Village, Jindong Countryside, Lang County, Linzhi City, Xizang Autonomous Region, China, is described herein based upon the integrative taxonomic results combining molecular phylogenetic systematics and morphological characteristic comparisons. Our molecular phylogeny was inferred by combining three mitochondrial gene fragments (16S/CO1/ND2), and it indicated a distinct differentiation between the new species and C. tibetanus species complex, with obvious genetic distances (16S 9.9-11.8%/CO1 16.5-18.2%/ND2 16.6-18.5%) detected, supporting its validity. Morphologically, the new species can be easily distinguished from its congers by the following characters: (1) medium size (SVL 48.58-50.92 mm), (2) tubercles on dorsum sparse, (3) tail segments absent and tubercles on tails absent, (4) supralabials 10-12 and infralabials 8-10, (5) interorbital scales between anterior corners of the eyes 28-32, (6) scale rows at midbody 96-98, (7) ventral scales between mental and cloacal slit 145-153, (8) ventral scale rows 41-45, and (9) 4 to 5 white-yellow transverse bands with brown dots and black merges between the nape and sacrum. The description of C. laevissp. nov. increased the total species number of C. tibetanus group to three, and the total Cyrtodactylus species number in Xizang to six and in China to eleven. The new species is currently only known from the type locality with its extremely small populations and needs future surveys to reveal its distribution range, population status, natural history, and mechanisms so that the new species can coexist with Altiphylax medogense.
Keywords: Cyrtodactylus laevis sp. nov.; Yarlung Zangbo River; molecular phylogeny; morphological characters; taxonomy.