†FAMILY AUSTROBALANIDAE NEWMAN & ROSS, 1976

Diagnosis: Four-plated shells with thin-walled parietes; paries smooth internally, lacking ‘an inflected basal margin’; scutum without adductor ridge, articular ridge moderately prominent, adductor pits for depressor muscles absent; tergum with articular furrow wide, spur confluent with basirostral angle.

Comment: Chan et al. (2017a) conducted a molecular analysis of pachylasmatids, bathylasmatids and tetraclitids. Austrobalanus formed a basal relationship with the clade containing bathylamatids and tetraclitids. Molecular evidence therefore supports the family status of Austrobalanidae .

† Austrobalanus Pilsbry, 1916 (Eocene–Recent) (three species)