Schizothorax nudiventris can be distinguished from its congeners by a combination of the following characters: snout blunt; upper lip thin; lower lip developed, trilobed, the median lobe minute, the lateral lobes forming a splayed. Postlabial groove continuous. Thorax scaleless in mature individuals; distal onefourth of last unbranched dorsal-fin ray soft and articulated, proximal three-fourths of it strong, with 15−21 serrae along its posterior edge; pelvic-fin origin beneath or posterior to vertical through dorsal-fin origin; irregular black spots scattered along lateral line on flank; eye diameter mean 92.0 % of maxillary barbel. Schizothorax nudiventris is further distinguished from the sympatric S. lissolabiatus Tsao and S. dolichonema Herzenstein by the absence (vs. presence) of a horny sheath on the lower jaw and having a smooth, trilobed lower lip (vs. bi-lobed in S. lissolabiatus and papillated and single-lobed lower lip in S. dolichonema). Schizothorax nudiventris is further distinguished from another species from the same drainage, S. yunnanensis, by having a continuous (vs. discontinuous) postlabial groove; last unbranched dorsal-fin ray strong (vs. soft); length of barbels equal to or longer (vs. shorter) than eye diameter. Schizothorax nudiventris resembles the sympatric S. lantsangensis Tsao, with which is shares a scalesless thorax, lower lip tri-lobed and postlabial groove continuous, but differs from it in having larger eyes [diameter 57.2−160.0 % (mean 92.0) maxillary barbel vs. 33.9−60.1 % (mean 46.1)]; scales in transverse series from dorsal-fin origin to lateral line 27−34 (12*) (vs. 33−40 (9*)); median lobe of lower lip distinct, free and smooth (vs. indistinct and covered with papillae) (Ref. 80483).