This species is distinguished from its congeners by the following charcters: with four branched rays on anal fin (vs. 5); differs with its congeners except munduruku, with large yellowish-white spots along the body, and dark brown spots on fins (vs. body covered by conspicuous small greenish-yellow dots of similar size on head, trunk and fins in wolverine; yellowish-white spots on posterior part of the body moderate in size, usually smaller than pupil in xikrin; all fins covered by large yellowish-white spots in xavante); differs from its congeners except wolverine by having a narrow, bar-shaped connection strut between anterior process of compound pterotic and main body, leaving a large posterior gap (vs. connection strut as a continuous sheet); with pectoral-fin spine length 25.1-29.9% of SL (vs. 32.1-38.4% in wolverine and 32.1-35.7% of SL in xikrin); differs from xikrin by the transverse process of first dorsal-fin pterygiophore sutured to the transverse process of the second pterygiophore (vs. no contact between the transverse processes of first and second dorsal-fin pterygiophores); differs from xavante by caudal peduncle depth 9.7-11.3% of SL (vs. 11.5-12.9% of SL); by the narrow nasal bone plate (vs. broad nasal, sometimes slightly triangular); by having nuchal plate exposed, and covered by odontodes (vs. nuchal plate covered by thick skin and usually lacking odontodes) (Ref. 125999).