Other genera allied to the two preceding are Aulacocephalus from Mauritius, Reunion, and Japan; and Myriodon from the coasts of Australia.
Diploprion.—Body rather elevated, compressed, with small scales. All the teeth villiform; teeth on the vomer and palatine bones. Two dorsal fins, the first with eight spines; anal with two. Præoperculum with a double denticulated limb.
Fig. 153.—Mesoprion monostigma.
The single species known (D. bifasciatum), is very common in the East Indian Archipelago, and on the coasts of Southern China and Japan. It is of small size, and ornamented with two broad black cross-bands.
Mesoprion.—Body oblong, compressed, covered with scales of moderate size. Teeth villiform, with canines in both jaws; teeth on the vomer and palatine bones. One dorsal fin, with ten or eleven, rarely with more spines; anal fin with three. Præoperculum serrated; in some species (Genyoroge) a more or less distinct spinous knob projects from the surface of the interoperculum, and is received in a more or less deep notch of the præopercular margin.
Fig. 154.—Opercles a, of Mesoprion; b, of Genyoroge; o, knob received in a notch of the præoperculum.
About seventy species are known from tropical seas in both hemispheres, but it is noteworthy that the species with the peculiar protuberance of the interoperculum are confined to the Indo-Pacific. The coloration is much more simple than in the small-scaled Serrani, a uniform hue of greenish, pink, or red prevailing; species with longitudinal bands are scarce, but not rarely dark cross-bands or a large spot on the side occur. The majority of the species remain within very moderate dimensions, specimens exceeding three feet in length being scarce. They are generally eaten, and some of the species belong to the commonest fishes of the tropics, as M. bengalensis, chrysurus, gembra, griseus, and others.
Glaucosoma from Japan and Australia is allied to Mesoprion.