Labrichthys unilineatus is a small and dark-coloured species, making it easily overlooked even though it is not uncommon on Maldivian reefs. There is only one species in the genus, with L. cyanotaenia Bleeker being its synonym.
Details
§ 01
size
Max. 17.5 cm
color
Dark brown, almost black. Juveniles with 2 white lines along sides, lower one lost with growth. Females with yellow lips and pale blue caudal margins. Males with dark blue lines on head and body. Broad yellow bars on sides behind pectoral.
This species is found in areas with plenty of coral cover, where it feeds on the polyps of the coral.
distinctive characters
The dorsal fin has 9 spines and 11-12 rays, the anal fin has 3 spines and 10-11 rays, the pectoral fin has 14-15 rays, the preopercular margin is covered by scales, the top of the head is scaled to the nostrils, the lower part of the head is scaled anterior to the eye, the body depth is 2.6-3.2 in standard length, the lips are thick and fleshy forming a tube when closed, and the caudal fin is strongly rounded.