Pervagor janthinosoma (Bleeker 1854)

Body and head color variable. Blackish to dark bluish branchial blotch extending dorsally to level well above the lower margin of eye and may include ventrally the pectoral fin base and axil. Iris usually dark brown. Orange to red caudal fin soft dorsal and anal fins clear, orange or yellow with spots; pectorals clear. Scale spinulation at midbody closely packed. Male scale ridge rugosities develop at about 80 mm SL developed. Strong first dorsal spine. Large pelvic fin rudiment narrowly attached to posterior margin of ventral flap.

Dorsal spines (total): 1 - 2; Dorsal soft rays (total): 29 - 34; Analspines: 0; Analsoft rays: 26 - 30

Occurs in shallow lagoons and seaward reefs to a depth of about 15 m; common in coral-rich areas. Secretive species (Ref. 9710, 48637) among rocks, sponges or in crevices on the bases of large coral formations. Adults usually form pairs but often only one is observed while the other one is hiding (Ref. 48637).