Distinctive Characters: Dorsal fin with 10 spines and 9-10 rays. Anal fin with 3 spines and 8 rays. Pectoral fin with 16-17 rays. Body depth 2.5 times in standard length. Body moderately deep, but fusiform. Pectoral fins long, reaching level of anus. Dorsal and anal fins scaleless. Eye large, just above line from tip of upper jaw to middle of caudal fin. Interorbital space convex. Caudal fin deeply forked.
Colour: Overall dark purplish-brown to bluish; silvery or whitish on lower sides and belly. Dorsal and caudal fins brownish to slightly yellow, other fins whitish to translucent.
Habitat and Biology: Occurs over rocky bottoms between about 50 to 200 m. Distribution: Tropical Indo-Pacific.
Remarks: Paracaesio sordidus can easily be distinguished from the related P. xanthurus on the basis of colour pattern. P. sordidus is sometimes seen in small schools by divers on deep outer reef slope.