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. The dusky spinefoot is found on the coast of eastern Africa from Mozambique northwards into the Red Sea, and also the Comoros, Madagascar, and the Mascarene Islands. Its presence in the Persian Gulf needs to be confirmed. Recorded first in the Mediterranean Sea in 1955 off Israel, following entry via the Suez Canal, it fast expanded across the eastern Basin and now reaches westwards as far as the French Mediterranean coast and the Adriatic Sea. It is found at depths between 2 and 40 m (6 ft 7 in and 131 ft 3 in) in waters over hard substrates, such as coral and rocky reefs.
