Body depth slightly less than head length, depth contained 2.4 to 3.1 times in standard length (for fish 13 to 22 cm standard length); caudal-peduncle depth 12.0 to 14.0% of standard length. Eye diameter greater than snout length, eye diameter contained 4.1 to 5.3 times in head length; preopercle rounded, the posterior edge distinctly serrate with a large spine (usually hidden by skin) directed downward and forward at the “angle.” Gill rakers 6 to 8 on upper limb, 16 or 17 on lower limb, 22 to 25 total. Dorsal fin with XI spines and 17 to 19 rays; anal fin with III spines and 9 rays; pectoral fins with 16 or 17 rays; caudal fin rounded. Scales smooth: lateral-line scales 55 to 61; lateral-scale series 68 to 77.
Colour: Head, body, and median fins olivaceous or light brown, irregularly blotched, and barred with dark brown, and densely spotted with orange; head, body, and all fins with scattered, small white spots; pectoral fins orange or yellow with faint brownish reticulations.

Western Atlantic: Bermuda, south Florida, Bahamas, Cuba, West Indies, Panama, Venezuela, and southward to the state of São Paulo, Brazil. Boulenger’s (1895) record of E. afer from the Falkland Islands is based on the stuffed specimen reported by Gunther (1859); this specimen probably came from Brazil and was mislabelled or mixed up with specimens from the Falklands.

See "Ecology" under the genus Alphestes description. Thompson and Munro (1983) estimated the number of eggs in 4 females to range from 157 512 to 223 706 per fish.
Size: Maximum total length about 33 cm.

Maximum total length about 33 cm.

Smith (1971) synonymized the eastern Pacific species Alphestes galapagensis Fowler, A. Fasciatus Hildebrand, and A. immaculatus Breder with the Atlantic species A. afer. Heemstra and Randall (1993) believe that these amphi-American populations are distinct species, as indicated by their different colour patterns and the greater depth of the caudal peduncle in A. afer. The distinctive dark crossbars on the pectoral fins of A. immaculatus are lacking in A. afer, and A. afer usually has 23 or 24 total gill rakers, whereas A. immaculatus has 20 to 22 gill rakers. Furthermore, Johnson and Keener (1984) have shown that the dorsal- and pelvic-fin spines of larval A. afer differ considerably in their distinctive ornamentation from the spines of A. immaculatus (which they refer to as the Pacific population of A. afer). Also these authors concluded that the striking differences in spine morphology suggest that these two populations are specifically distinct.