A mountain giant: description of the largest known species of the genus Scincella Mittleman, 1950 (Squamata, Scincidae) from Yunnan Province, China

A remarkable new species of skink, Scincella gigas sp. nov., is described from Yunnan Province, China, based on integrative morphological and molecular evidence. The new species represents the largest known member of the genus Scincella, with the adult female holotype attaining a snout-vent length of 125 mm and a total length exceeding 316 mm despite possessing a partially regenerated tail. Scincella gigas sp. nov. can be distinguished from all congeners by a unique combination of morphological characters, including three prefrontal scales, relatively short limbs that fail to meet when adpressed, the third pair of chin shields separated by four small scales, 28 midbody scale rows, 80 paravertebral scale rows, and broad dorsolateral stripes with distinctly serrated margins.

Phylogenetic analyses based on concatenated mitochondrial gene fragments (12 S, 16 S, CO 1, and Cyt b) recovered the new taxon as a distinct lineage within Scincella, although its precise phylogenetic relationships remain unresolved. The new species exhibits substantial genetic divergence from all examined congeners (≥ 4.4 % in 16 S and ≥ 14.2 % in CO 1). Scincella gigas sp. nov. is currently known only from montane mixed forests and associated alpine meadows in Fengyi Town, Dali Bai Autonomous Prefecture, Yunnan Province, China, at an elevation of 2,790 m a. s. l.

The discovery of such a conspicuous and exceptionally large species suggests that the diversity of montane Scincella in southwestern China remains insufficiently documented.