This species is distinguished from the other members of the O. brandtii species group (brandtii, elsae, merga) by having a slightly emarginate caudal fin (vs. forked in brandtii, deeply emarginate in elsae, merga); pelvic fin not reaching to origin of genital papillae (vs. reaching to or beyond anus in brandtii and many elsae, merga); caudal peduncle 1.5–2.1 times longer than deep (vs. 2.5–3.2 in brandtii, 2.3–2.9 in elsae, 2.0–2.5 in merga); and a mottled or marbled flank pattern (vs. usually with irregularly shaped and spaced, dark-brown bars or vertically elongate blotches on flank posterior to dorsal-fin origin, much wider than interspaces, often fused into a plain brown pattern on flank in front of dorsal-fin base in brandtii; usually with irregularly shaped and spaced, rarely regularly shaped and spaced, dark-brown bars, often split in middle, or flank almost plain brown in elsae; with many, narrow, pale-brown bars, usually much more narrow than interspaces, often dissociated in vertically elongate blotches on flank and dorsal saddles, rarely mottled in merga) (Ref. 125990).