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This species is distinguished from its congeners by the following set of characters: body elongated, round in cross section anteriorly, laterally compressed posteriorly, dorsal profile slightly convex to start of dorsal fin, straight more posteriorly; ventral profile convex in head region, then straight posteriorly; head large, 15.7-20.4% standard length, with dorsally and laterally bulging adductor muscles; snout truncated; mouth wide, terminal; absence of eye; 4 pairs of barbels; 2 mandibular, 1 maxillary and 1 nasal barbel pair; nasal and inner mandibular barbels shorter than maxillary and outer mandibular barbels; maxillary and outer mandibular barbels reaching posterior border of pectoral fins when folded back; large gill opening, extending to slightly above pectoral-fin base; gill membranes united with isthmus; absence of scales; caudal peduncle laterally compressed, 9.3-16.9% of standard length; dorsal fin long, with 22-23 soft rays (xiii-xiv unbranched/8-9 branched), originating in advance of pelvic fin origin; anal fin long, with xiii-xvii unbranched rays, starting opposite dorsal fin ray number 9, ending opposite base of last dorsal fin ray; pectoral fin vestigial, consisting only of modified pectoral fin spine covered by thickened skin; pelvic fin short, wide, with rounded margin, with ii-iv unbranched and 2-4 branched rays; caudal fin with rounded posterior margin, with 8-9 branched and 2-4 dorsal unbranched and 2-4 ventral unbranched rays; head skeleton well ossified; neurocranium with a single large cranial fontanelle, no epiphyseal bridge connecting frontals in dorsal midline; lateral neurocranium wall with large trigeminofacial foramen; supraoccipital with long, narrow and pointed crest; opercle small and subtriangular; and jaws massive, dentary and premaxilla studded with numerous rows of closely set, recurved villiform teeth (Ref. 137782). |
