The identity of Schizothorax griseus Pellegrin, 1931, with descriptions of three new species of schizothoracine fishes (Teleostei: Cyprinidae) from China

Abstract

The identity of Schizothorax griseus Pellegrin, 1931, is clarified and the species redescribed. Three new species previously identified as S. griseus are described: S. nudiventris, from the Lancang Jiang, China; S. heterophysallidos, from the Nanpan Jiang, China; and S. beipanensis, from the upper Beipan Jiang, China. The group comprising Schizothorax griseus, S. nudiventris, S. heterophysallidos and S. beipanensis can be diagnosed from other members of this genus by the absence of an obvious horny sheath on the lower jaw; lower lip developed with three labial lobes in mature individuals; postlabial groove continuous, with a small labial lobe present in the middle of the lower lip; last unbranched dorsal-fin ray strong, its posterior edge with numerous serrae; and scales absent on ventral surface between pectoral fins in adults (except in S. griseus). Schizothorax griseus differs from S. nudiventris, S. heterophysallidos and S. beipanensis by the presence (vs. absence) of concealed scales in the skin on the ventral surface between the pectoral fins in adults; the presence (vs. absence) of a shallow ethmoidal groove before the nostrils; and having barbels much longer than eye diameter (eye diameter 33.4–93.7 % (vs. 57.2–160.0) of maxillary-barbel length). Schizothorax nudiventris is distinguished from S. heterophysallidos and S. beipanensis in having only the proximal ¾ (vs. entirety) of the last unbranched dorsal-fin ray strong; pelvic-fin origin opposite or posterior (vs. opposite or anterior) to vertical through dorsal-fin origin; and irregular black spots present (vs. absent) on side of body. Schizothorax heterophysallidos is distinguished from S. griseus, S. nudiventris and S. beipanensis in having a larger posterior chamber of the air bladder (vs. posterior chamber as large as, or slightly larger than, anterior one), length of posterior chamber 3–6 (vs. 2) times length of anterior chamber. Schizothorax beipanensis is distinguished from S. griseus by the absence (vs. presence) of scales on the thorax in mature individuals; absence (vs. presence) of black spots on side of body; and having the maxillary barbel 58.5–120.1 % SL (vs. 33.4–93.7 % SL).