Distinctive Characters: Dorsal fin with 9 spines and 10-11 rays. Anal fin with 3 spines and 9-10 rays. Pectoral fin with 13 rays. Body depth 3.7-4.5 in standard length. Small scales on cheek, opercle and nape. Lips thick, the lower strongly bi-lobed. Caudal fin slightly rounded.
Colour: Adults dark anteriorly and pale posteriorly. Females grey and pale yellow, males dark blue/ black and bright yellow. Juveniles with bright yellow dorsal stripe.
Habitat and Biology: Commonly seen moving over the reef slopes to depths of 42 m. Feeds on ectoparasites (and mucus) of other fishes.
Remarks: Labroides bicolor is a cleaner wrasse and is the largest of the genus. It is more inclined to follow larger fishes in its cleaning operations than other cleaner wrasses.