Alveolinidae have fusiform tests that are elongated along the coiling axis. The chambers of A. quoi are divided into chamberlets and numerous apertures occur in several longitudinal rows. Living specimens are characterized by a brownish colour, due to their diatom endosymbionts.
The genus Borelis possesses spherical to fusiform tests, chambers are divided into chamberlets. Multiple apertures occur in a single row. Living specimens appear brownish in colour due to diatom endosymbionts