Sarcastic fringeheads are the largest of all fringeheads (Eschmeyer 1983). They can grow to be 30.0 cm in length (Williams 2000). They possess the clinid family characteristics of a long dorsal fin, as well as wavy, fringe-like cirri on their heads ("PBS: Sea Dwellers" 2000). They are specifically known for their extremely large mouths. This is due, in part, to their characteristically long maxillary that extends nearly to the back edge of the gill cover (Gotshall 1989).
The bodies of the sarcastic fringeheads are long, slender and compressed. They possess unbranched pectoral fin rays (CALCOFI 1996). In addition, the dorsal fins extend continuously from the head to the base of the tail fin. Further, the anal fin extends from vent to the base of the tail fin (Barnhart 1936).
Fringeheads are generally brownish-gray and typically mottled with either red or green patches ("A Learning Link to the Aquarium of the Pacific" 2000). The dorsal spines possess two ocelli, one between the first and second spines, and the other between the fifth and ninth spines (Gotshall 1989). These ocelli are generally blue and outlined by a yellow ring ("A Learning Link to the Aquarium of the Pacific" 2000).