Appearance
The dusky spinefoot has a compressed body which Has a depth which fits into its standard length 2.1 to 2.8 times. There is a single row of incisor-like teeth in the jaws, each with 1 or 2 lateral cusps. The dorsal fin contains 13-14 spines and 10 soft rays while the anal fin has 7 spines and 9 soft rays. The caudal fin is truncate. This species attains a maximum total length of 30 cm (12 in), although 20 cm (7.9 in) is more typical. The colour is variable, it is normally olive green to dark brown with a mottled pattern. The pectoral fins are hyaline-yellow and there are dark bars on the caudal fin

