Goniistius is a subgenus of marine ray-finned fishes, traditionally classified as being within the genus Cheilodactylus and belonging to the family Cheilodactylidae, known as morwongs, although this name is not unique to this family and the true taxonomic placement of this taxon requires clarification.

[1] The name of the subgenus is a compound of gonio meaning “angle” and istios which means “sail”, Gill did not explain what his name alluded to but he may have been referring to the deep incision between spiny and soft-rayed parts of the dorsal fin of the type species.

These analyses suggest that the a monophyletic Cheilodactylidae would contain only two species, the southern African C. fasciatus and C. pixi.

[3][4][5] The following species belong in this subgenus:[4][5] Goniistius is characterised by having an oval, compressed body.

The mouth has thick, fleshy lips, In most species there is a bony processes on the frontal bone in line with the centre of the eye or it is in the front of the mouth in two species while in G. rubrolabiatus and G. zonatus it is absent.