About Caesioperca rasor (Richardson, 1839)
Caesioperca rasor, commonly called the barber perch, is a laterally compressed, deep-bodied fish that reaches a maximum total length of 26 centimetres (10 inches). Females and larger juveniles of this species are pinkish in color, with a large black vertical bar on the flank toward the posterior end, and a blue streak located just under the eye. Smaller juveniles have the same coloration and markings plus an additional black head. Males share similar base markings, but their overall body hue is either silvery or yellowish. Males also have blue margins along their fins and a small blue spot on each individual scale. This species can be distinguished from its close relative, the butterfly perch, by its more slender body shape. Male Caesioperca rasor are also more blue overall than male butterfly perch, and have a darker vertical bar rather than a blotch on their flank. These two related species will sometimes form mixed shoals together.