This species is distinguished by the following characters: differs from G. barreimiae by having a greenish-brown or grey flank without or with slight mottling (vs. strongly mottled), faint lateral stripe in some individuals (vs. absent), no orange midlateral scales on the flank (vs. present), no orange spot at the upper opercle (vs. present), dorsal-fin tip not white (vs. white), and gill rakers on the lower limb of the first gill arch 12-14 (vs. 15-18); differs from G. gallagheri by having bold, dark-brown or grey scale pockets on the dorsal surface and dark-brown or grey scale margins on the flank which are clearly darker than the centre of the scales (vs. scale pockets and scale margins same colour as or slightly darker than centre of scales) (Ref. 122023).