Gymnocranius obesus

Gymnocranius elongatus differs in having a deeply forked caudal fin, the median rays shorter than eye diameter (vs. moderately forked caudal fin, the median rays longer than eye diameter) and lower edge of eye level with snout tip to middle of caudal-fin fork (vs. lower edge of eye above line from snout tip to middle of caudal-fin fork).

Gymnocranius frenatus differs in having 3 or 4 oblique, wavy blue lines on snout and cheek (vs. no blue markings on snout or cheek).

Gymnocranius grandoculis differs in having horizontal, wavy blue lines present in specimens >20 cm TL (vs. no blue markings on snout and cheek).

Gymnocranius microdon differs in having vertically elongate blue spots on snout and cheek (vs. no blue markings on snout and cheek).

Gymnocranius euanus differs in having 4½ scale rows between lateral line and base of middle dorsal-fin spines (vs. 5½).

Gymnocranius satoi differs in having body silvery (vs. dark narrow bars on body); blue speckles on snout and cheek (vs. no markings) and inner edge of caudal-fin lobes convex (vs. straight).

Gymnocranius griseus differs in having a dark bar running from below sixth dorsal-fin spine to mid pelvic-anal space (vs. dark bar running from below sixth dorsal-fin spine to anal-fin origin) and 9–11 front scales on the top of head (vs. 4–6).