Rhamdia itacaiunas Silfvergrip 1996

Rhamdia itacaiunas is diagnosed from all congeners by the pectoral fin spine with serrations on both sides; caudal fin upper lobe pointed and longer than lower lobe; mouth deeply cleft to near the vertical at the anterior margin of the eye; eyes in advanced position, distinctly closer to the snout than to the operculum hind margin; adipose fin 23.3-28.4% of SL or 96.2-127% of HL; maxillary barbel 41.2-53.8% of SL or 190-231% of HL; broad tooth plates.

Dorsal spines (total): 1; Dorsal soft rays (total): 6