The parrotfishes, family Scaridae, are characterized as specialized perciform fishes that closely associate with reefs and are primarily tropical in distribution (Schultz 1958, 1969 and Nelson 1994). Rosenblatt and Hobson (1969) revised the systematics of eastern Pacific parrotfishes, recognizing three genera comprising six species. Scarus is considered the typical parrotfish genus, with four species in the eastern Pacific. Nicholsina, the more primitive (or plesiomorphic) genus, is monotypic in the eastern Pacific. Calotomus, the third genus, is Indo-Pacific in origin and rare in the eastern Pacific. Nicholsina denticulata (Evermann & Radcliffe, 1917), the loosetooth parrotfish, is a smaller, less colorful species compared to the members of the genus Scarus occupying the Panamic Region.