Rockmover Wrasse

The rockmover wrasse is a colorful fish, 27–30 cm (11–12 in) in length. It has an oblong, laterally compressed body and a wedge-shaped head. Its head is scaleless except for two scales on the upper part of the gill coverings and an almost vertical row of small scales behind each eye. Juveniles and adults have markedly different appearances. In juveniles, the first two dorsal fin spines are long and extended, drooping over the fish's forehead to form a "cowlick". As the fish matures, the elongated rays are lost. The adult fish has a dark greenish-brown body with an elongated white spot on each scale. Its head is gray-blue with brown lines radiated from the eyes. Two black spots occur in front of the dorsal fin and a wide vertical white bar is found on the base of the caudal fin. The posterior part of the caudal fin and the pelvic fins are black. Juveniles found in Hawaii are usually green and those in the western Pacific are burgundy to brownish. Both are spotted in white.

The difference in appearance between juvenile and adult N. taeniourus is so striking, the common name "rockmover wrasse" is used for adults and "dragon wrasse" is used for juveniles.

They are widely distributed in tropical Indian Ocean and Pacific Ocean reefs and lagoons.

Although little is known about reproduction of these fish, like other wrasses, they probably are able to change sex and are pelagic spawners, broadcasting eggs and sperm into the water column.

The genus "Novaculichthys", in Latin Novacula means razor, and ikhthús in Greek, means fish., while the specific name "taeniourus" from Greek tainía means ribbon, and oura means tail.