Body inflatable; when not inflated, elongated moderately deep, round with flat belly. Short-based dorsal and anal fins, posterior in position, the origin of the former slightly in front of the later. Caudal fin moderately emarginate lanulated. Wide based pectoral fin, with round posterior edge. Pelvic fin absent. Head large with blunt snout. Mouth small. Two large teeth in each jaw with median suture. Gill slit in front of pectoral fin base. No scales, but small spinules on the belly and on the dorsal surface in a patch which does not extend posteriorly beyond pectoral fin margin. Two lateral lines, both extending to the head and curving around the eye.
back-dark grey (adults) to olive-green with dark blotches (young). Side of head and flank-silvery, often with golden sheen. Belly-white.
common 5-30 cm (max. 40 cm).
Lagocephalus suezensis: small spinules on the dorsal surface extending back to the origin of dorsal fin.
Torquigener flavimaculosus: truncated caudal fin.
Sphoeroides pachygaster: smooth skin.
Chilomycterus spilostylus: three-rooted spines, fixed in erected position.
BIOLOGY / ECOLOGY
When provoked capable of inflation of the body, by rapidly drawing water (or air) into its body. Feeds on benthic invertebrates. Eggs and larvae planktonic.