Distinguished from all other genera of Loricariinae by usually possessing one to three premaxillary teeth (although these are often missing) that are much reduced in size, particularly in comparison to the dentary teeth. The following combination of characters also differentiates this genus from all other members of the Loricariinae: lips with globular papillae on surface, except for some areas close to the opening of the mouth where the papillae are prolonged and digitiform; distal margin of lower lip with short, triangular filaments; premaxilla very reduced; the non-reduced condition of the premaxilla is represented; abdomen covered by plates, medial plates small and rhombic between lateral abdominal plates; caudal fin with 14 total rays (12 branched); orbital notch absent; five lateral series of plates; dorsal fin spinelet absent; preanal plate present, large and solid, and of irregular, polygonal shape. Trunk and caudal peduncle becoming more compressed posteriorly for last seven to 10 plates (Ref. 87853).