Type species. Pleurotoma circinata Dall, 1873 by original designation. This is a North Pacific Ocean species with a large bathymetric range (6 to 300 m) according to Abbott (1974). Dall (1890) mentioned this species as “inoperculated” when describing Pleurotoma (Leucosyrinx) goodei. Powell (1966) synonymized Aforia with Irenosyrinx Dall, 1908 (Type species: Pleurotoma (Leucosyrinx) goodei Dall, 1890 from southern Chile) despite some differences in the operculum that he considers irrelevant. Later Bouchet and Warén (1980) proposed full generic status to Irenosyrinx based on the fact that the type species of Aforia is a shallow-water species from the North Pacific while Irenosyrinx, an Eastern Pacific species, is abyssal. Recently Bouchet et al. (2011) accepted Irenosyrinx as a subgenus of Aforia.