It is a marine fish and the largest of the hawkfish family with maximum size of 60 cm (24 in) in total length.

The giant hawkfish was first formally described in 1846 by the French zoologist Achille Valenciennes with the type locality given as the Galápagos Islands.

They have large heads with a blunt snout and have a fringe of cirri on the posterior margin of the anterior nostril.

The upper margin of the preoperculum either has small serrations or is smooth and the gill cover has 2 flattened spines.

The head has thick, golden-brown bands which also have black margins bordered by slender blue edges, eadiating out from the eyes.

It occurs from southern Baja California and the northern Sea of Cortez to Ecuador, including all of the offshore islands in that region.