Males of Naso hexacanthus display a large pale blue area on the upper head and dorsoanterior body, as well as some pale blue vertical lines and spots anteriorly on the sides of the body during courtship.
Details
§ 01
size
Max. 75 cm
color
Dark brown to pale bluish grey dorsally, yellow brown ventrally. Edges of opercle and preopercle often dark.
This species is commonly found in depths of up to 150 m, often in large groups. It feeds on larger zooplankton such as crab larvae, arrow-worms, and pelagic tunicates.
distinctive characters
This species has a dorsal fin with 6 spines and 26-29 rays, an anal fin with 2 spines and 27-30 rays, and 17-18 pectoral rays. The body depth of subadults is 2.0 in standard length, while adults have a body depth of 2.75. The dorsal profile of the head slopes and is smoothly convex, and the caudal fin is emarginate in young individuals and truncate in adults.