Diagnosis. Shell thin, typically 8—13 mm long, white or off-white, biconic and moderately high-spired, whorls weakly sculptured or smooth, except for spiral grooves on base; aperture semi-lunate, typically lacking labial or parietal denticles or heavy callosities. Most with paucispiral protoconch indicative of nonpelagic development.
Remarks. Astyris species occur in cold waters at shallow to offshore depths. This genus is poorly understood and has long acted as a catchall for an array of species, usually including small, colder water biconic forms. In Radwin's (1978) revision of the western Atlantic Columbellidae, Astyris was the one genus that he could not figure out how to assess. So he simply listed 32 species that had been variously attributed to it without discussion.
The type species of Astyris, A. rosaceum (Gould), is considered circumboreal by Oldroyd (1927), who listed it as part of the northeast Pacific fauna. The type was collected off Massachusetts. The species is similar to A. amiantis but slightly pinkish; whether they are related or conspecific remains to be seen. The apices suggest nonpelagic development, so the likelihood of genetic continuity throughout such a large range is unlikely.