This species is distinguished by the following characters: typically having the posterior margin of pectoral-fin spine only with perpendicularly directed serrations, with some specimens variably presenting some serrations smoothly bent towards the tip of the spine; presence of contact between the parieto-supraoccipital and nuchal plate; with a fold in the middle portion of the lower lip. Colouration: along flank midline are longitudinal series of 3-5 moderate-to large-sized dark brown or black blotches; some specimens have coalescent blotches, forming a wide and irregular stripe; anterior portion of dorsal fin with conspicuous concentration of dark brown or black chromatophores, not forming small dark markings; pectoral fin with conspicuous concentration of dark brown or black chromatophores, not forming small dark markings; caudal-fin lobes with conspicuous dark brown or black bands; absence of a dark brown or black bar crossing the orbit (Ref. 138497).