The Indo–Pacific reef-dwelling comatulid crinoid Comaster multifidus (Müller, 1841) is the type species of the genus Comaster Agassiz, 1836. Re-examination of the type specimen of C. multifidus shows that it does not conform to the concept of the species as currently applied and does not belong in the genus as currently diagnosed. Instead, it falls within Comanthina A. H. Clark, 1909, and is identical to Comanthina variabilis Bell, 1882. Comanthina thus becomes a junior synonym of Comaster because Actinometra nobilis Carpenter, 1884, the type species of Comanthina, is clearly congeneric with A. variabilis. Species currently assigned to Comanthina are herein transferred to Comaster. The other species currently included in Comaster represent a distinct taxonomic group and are herein transferred to the next most senior available genus, Phanogenia Lovén, 1866. The holotypes of the type species of Comaster and Phanogenia are redescribed in detail.