A New Species of the Genus Scincella Mittleman, 1950 (Squamata: Scincidae) from Sichuan Province, Southwest China, with a Diagnostic Key of Scincella Species in China

The genus Scincella Mittleman, 1950 of the family Scincidae currently includes 38 species. To date, however, taxonomic assessment remains challenging. Here, phylogenetic analyses based on DNA sequences of four mitochondrial genes supported a putative new species from Sichuan Province, Southwest China, as an independent lineage. Uncorrected genetic distance of 16S rRNA between the new species and closest congener was 8%, and the population was morphologically distinguishable from all other known congeners. We herein describe the Scincella population as a new species based on both phylogeny and comparative morphology. The new species can be distinguished from its congeners by a combination of the following morphological characters: (1) body slender, mediumsized, snout-vent length 35.0-62.1 mm; (2) infralabials seven, rarely eight; (3) supraciliaries 5-7; (4) tympanum deeply sunk without lobules; (5) midbody scale-row counts 27-30; (6) dorsal scales smooth and enlarged, paravertebral scale-row counts 60-75, ventral scale row counts 46-59, gulars 25-30; (7) upper edge of lateral longitudinal stripes relatively straight with six rows of dorsal scales in middle; (8) number of enlarged, undivided lamellae beneath finger IV 9-11, number of enlarged, undivided lamellae beneath toe IV 13-16; (9) ventral side of tail densely ornamented with dark brown or black spots; and (10) grayish-brown discontinuous regular dorsal stripes 5-7, distinct black dorsolateral stripes, starting from posterior corner of eye and continuing to lateral side of tail. A diagnostic key to all Scincella members from China is also provided. The new species is currently only known from Wenchuan and Lixian counties, Sichuan Province, China, and brings the number of Scincella species in China to 12. This study emphasizes the incompleteness of knowledge on herpetodiversity in China.