Paracanthocobitis zonalternans differs from all its congeners by combination of the following characters: lateral line incomplete, ending near insertion of dorsal fin; dorsal fin with 9½-10½ branched rays; presence of axillary pelvic lobe; series of black blotches, usually without black stripe but with faint dusky stripe, along side of body, usually ending near dorsal-fin insertion; circular black spot on upper margin of caudal-fin base; black pigment extending from lateral stripe onto pectoral-fin base; absence of marmorated pattern anterior to origin of dorsal fin; dorsal saddles short, rarely connecting to lateral blotches; and upper caudal fin with 8 (occasionally 7) branched rays (Ref. 117351).