According to Oskars & al. (2015), the family includes only two genera: Cylichna and Toledonia. Shells minute to small, cylindrical to pyriform; apex sunken; aperture about as high as the shell, narrow posteriorly, wide and round anteriorly; columella vertical, largely deflected near the base, lesser posteriorly except in some species such as Cylichna bulloidea.
 

The specifics of the genus are chiefly anatomical – cf. G. W. Tryon: American marine conchology, Philadelphia 1873, p.102. Posterior terminal slightly to moderately projecting beyond the spire; anterior part of the columella sometimes twisted near the base.