This species is distinguished from its congeners in the O. tigris group by the following set characters, none of which are unique: male without suborbital groove; incomplete lateral line not reaching or reaching below the dorsal-fin base; scaleless on back and flank; with a median incision in the upper lip; individuals larger than 5.0 cm SL with a high dorsal adipose crest on the posterior-most caudal peduncle, the dorsal crest is not reaching to the vertical through the anal-fin base; pelvic-axillary lobe absent; deep caudal peduncle, its length 1.0–1.3 times its depth; flank with a marmorate pattern or with large, irregularly shaped and narrowly spaced dark-brown bars or blotches, usually more prominent on the flank behind the dorsal-fin base (Ref. 120397).