[2] Its body is streaked with horizontal bluish lines on a brown background color although over time it is able to change colour to become grey-blue overall.

[6] The dorsal and anal fin are bluish with a yellow reflection, with the base of the latter underlined by a fine black line.

A sharp erectile spine (comparable to a scalpel, thus the species name) at the base of the tail is a defensive weapon.

[8] Acanthurus mata inhabits usually steep slopes around coral reefs in depth range from 5 to 45m.

It is solitary when resting on the reef but may form small aggregation in the open water during feeding.