They are characterized by a deep body with small scales; eight or nine branched dorsal-fin rays; distal margin of the dorsal fin slightly convex; forked caudal fin; posterior chamber of air bladder well developed, not encapsulated, more or less conical, in direct contact with the capsule; strongly arched mouth, 1.5–2.0 times wider than long; and lower lip with a median interruption forming two lateral broadly triangular pads with deep furrows (Bănărescu & Nalbant 1995; Kottelat 1990).