Choerodon, Bleeker, 1847

Martin F., Martin F., 2017, A review of the tuskfishes, genus Choerodon (Labridae, Perciformes), with descriptions of three new species, Memoirs of Museum Victoria 76, pp. 1-111 : 40-41

Choerodon (Aspiurochilus) Fowler, 1956

Tables 2 & 4

Lepidaplois (Aspiurochilus) Fowler, 1956: 176 , type species –

Crenilabrus stejnegeri Ishikawa (= C. azurio ) by monotypy.

Diagnosis. Dorsal fin rays XII, 8 or XIII, 7, rarely XI, 9; anal fin rays III, 10; pectoral fin rays ii, 14, rarely 15, dorsalmost ray of moderate length 23.9–45.2% pectoral fin length, ventralmost rays shorter than those above, posterior edge of fin obliquely straight, dorsoposterior corner bluntly pointed, posteroventral corner angular to broadly rounded; body moderately deep, 34.8–45.9% SL, head depth 26.6–42.2% SL, caudal peduncle depth 12.2–16.8% SL; head blunt, dorsal profile of snout moderately steep to steep, snout length 9.9–16.7% SL; predorsal scales approximately 5–11, reaching forward on dorsal midline to or just in advance of posterior edge of preopercle, to above middle of eye or to somewhere between; cheek with small imbricate to mostly embedded scales in about 4–9 diagonal rows, posteriormost with about 9–17 scales to upper extent of free preopercular edge, reaching forward to or almost to corner of upper lip crease above mouth, with broad naked margin posteriorly and ventrally on preopercle; 1–4 rows (only about 2 scales in second row when present) of small scales on subopercle adjacent preopercular edge extending forward to or just short of anterior end of ventral preopercular margin, with about 6–11 scales in outermost row; each lateral line scale with unbranched to multiple branching laterosensory canal tube; scales above lateral line about 2½ or 3; cephalic sensory canal pores relatively few to moderately numerous confined to lines or short branches associated with major canals; second pair of canines in lower jaw directed anterodorsally and slightly laterally, often strongly curved laterally; dorsal and anal fins with low to very low basal sheath comprising 1–3 progressively smaller accessory scales at deepest; posterior lobe of dorsal and anal fins reaching at most to base of first anal spine, usually to or just short of hypural crease; caudal fin truncate to distinctly rounded or with concave posterior profile. (See Table 2 for additional meristic and morphometric ranges.) Bicolour pattern in adults of 3 of 5 species, dusky anteriorly and paler posteriorly, contrasting areas separated by diagonal interface.

Reaches moderately large size, ranging in maximum lengths of from about 225 to more than 430 mm SL.

Comments. Fowler (1956: 176) incorrectly referred Ishikawa’s (1904) Crenilabrus stejnegeri to Lepidaplois (= Bodianus ), separating it from the other five species he recognised as occurring in Chinese waters by a suite of characters, some of which conflicted with his diagnosis for that genus. The same characters were considered a justification for placing it in a new subgenus Aspiurochilus . Although clearly not a group name for an assemblage of Bodianus , the name is available for species within Choerodon to which C. stenjegeri (= C. azurio ) belongs. The subgenus comprises five species, one of which is described here as new. Species of this subgenus (fig. 1, clade 2) are most similar to those of the subgenus Choerodon (fig. 1, clade 3) in having a rather deep body without characteristic modifications, some differing from members of that assemblage in having XII, 8 rather than XIII, 7 dorsal fin elements and all retaining 14 branched, segmented rays in the pectoral fin as well as scales on the subopercle reaching to or almost to the anterior extent of the ventral subopercular margin. Five of the nine species of the subgenus Choerodon typically have 13 or 15–17 branched rays in the pectoral fin and only two of the nine species have scales on the subopercle reaching in advance of the midpoint between the corner of the preopercle and the anterior extent of the ventral subopercular margin, with several considerably more reduced. Most reach a moderate size exceeding 250 mm SL, although one, C. monostigma , has only been verifiably recorded to about 160 mm SL.