Fisheries and Aquatic Ecology Laboratory, Department of Zoology, Rajiv Gandhi University, Rono Hills, Doimukh, Itanagar, Arunachal Pradesh-791112, India. .
Fisheries and Aquatic Ecology Laboratory, Department of Zoology, Rajiv Gandhi University, Rono Hills, Doimukh, Itanagar, Arunachal Pradesh-791112, India..
Zootaxa. 2022 Mar 11;5115(1):122-130. doi: 10.11646/zootaxa.5115.1.8.
Paracanthocobitis hijumensis, new species, is described from the Hijum River, a tributary of the upper Brahmaputra River in Arunachal Pradesh, India. Paracanthocobitis hijumensis is distinguished from all five species of the P. zonalternans species complex, viz., P. zonalternans, P. nigrolineata, P. marmorata, P. triangula, and P. phuketensis in having a larger body size (46.5 65.6 mm SL vs. < 45 mm SL), and a complete (vs. an incomplete) lateral line terminating at the end of caudal peduncle (vs. at or just beyond the dorsal-fin insertion); and from the four species of the P. mandalayensis species complex, P. canicula, P. maekhlongensis, P. mandalayensis and P. pictilis in having a subortibal flap (vs. suborbital groove) in males, and in having fewer dorsal-fin branched rays (910 vs. 1013), and longer head (23.826.0% SL vs. 18.020.2). Paracanthocobitis hijumensis, a member of the P. botia complex, differs from the other nine species of this complex by the following combination of characters: presence of an axillary pelvic lobe, greater predorsal distance 47.951.8% SL, greater prepelvic distance 52.358.8% SL, longer head 23.826.0% SL, deeper body 18.423.1% SL, smaller eye 14.222.5% SL, and fewer branched rays on the dorsal-fin 9 (12)10 (1).
新物种拟尖口鮠（Paracanthocobitis hijumensis）产于印度阿鲁纳恰尔邦上布拉马普特拉河的支流希朱姆河。拟尖口鮠与 P. zonalternans 种复合体的所有 5 个物种（即 P. zonalternans、P. nigrolineata、P. marmorata、P. triangula 和 P. phuketensis）不同，具有更大的体型（全长 46.5-65.6 毫米，而小于 45 毫米）和完整的（而非不完整的）侧线终止于尾柄末端（而非止于背鳍起点处或稍超过背鳍起点处）；与 P. mandalayensis 种复合体的 4 个物种（即 P. canicula、P. maekhlongensis、P. mandalayensis 和 P. pictilis）不同，雄鱼具有亚眶下皮瓣（而非亚眶下沟），并且具有较少的背鳍分枝鳍条（9-10 个，而不是 10-13 个）和更长的头部（23.8-26.0%全长，而不是 18.0-20.2%全长）。拟尖口鮠是 P. botia 复合体的成员，与该复合体的其他 9 个物种不同，具有以下特征组合：存在腋胸鳍叶，更大的前背距 47.9-51.8%全长，更大的前腹距 52.3-58.8%全长，更长的头部 23.8-26.0%全长，更深的身体 18.4-23.1%全长，更小的眼睛 14.2-22.5%全长，以及更少的背鳍分枝鳍条 9（12）-10（1）个。
