Abstract
Four genera of Calliostomatidae are known from the northeast Pacific, Akoya, Calliostoma, Otukaia, and Xeniostoma. Fifteen holotypes and all species are illustrated and diagnostic information presented. Approximately one third of the species occur most commonly below 100 m, some species have been collected in excess of 1,000 m. Akoya titanium (McLean, 1984) and A. bernardi (McLean, 1984) are recognized as synonyms of A. platinum (Dall, 1890). Confirmed diet of the species, which are known, includes primarily sessile invertebrates and diatoms.