Similar families occurring in the area. Chaetodontidae and Pentacerotidae: mouth not highly protrusible; pectoral fins not much longer than head; no notch between spinous and soft-rayed parts of dorsal fin. Ephippidae: pectoral fins short, not reaching past anal-fin base; mouth not protrusible. Scatophagidae: IV analfin spines; pectoral fins short; head profile concave. Monodactylidae: mouth not highly protrusible; pectoral fins shorter than head; eye centered on horizontal axis through mouth.