Simipercis differs from all other pinguipedid genera in having 3 dorsal spines, a low naked fleshy nuchal crest, and the dorsal angle of the opercular bone broad, not forming a distinct exposed, pointed spine, and a combination of the following features: vomer and palatines lacking teeth, subopercle and preopercle entire, 10 abdominal and 20–21 caudal vertebrae, scales including those on the head and pelvic region large and ctenoid, interorbital with a single row of large scales, extending to, or just beyond anterior margin of eye, suborbital scales reaching a vertical between anterior margin of pupil and anterior margin of eye, and head and body moderately compressed (body width 1.3–1.55 in depth in adults) (Johnson & Randall 2006).
Johnson, J.W. & J.E. Randall. 2006. Simipercis trispinosa, a new genus and species of sandperch (Perciformes: Pinguipedidae) from eastern Australia. Memoirs of the Museum of Victoria 63(1): 57-64.