The family Callanthiidae contains two genera, Callanthias (with seven species) and Grammatonotus (with six nominal species). Authors William D. Anderson, Jr., G. David Johnson, and Carole C. Baldwin provide characters that distinguish callanthiids from other percoids and that distinguish Callanthias from Grammatonotus, descriptions of Callanthias and its seven species, a key to the species of Callanthias, and comments on other aspects of the biology of the species of the genus. The authors’ initial interest in the splendid perches emanated not from their spectacular coloration but from specific features of their morphology and their bearing on possible relationships to other perciform fishes. Color illustrations.