†FAMILY BATHYLASMATIDAE NEWMAN & ROSS, 1971 (PALAEOCENE–RECENT)

Diagnosis: Wall of six plates; parietes solid or tubiferous; when tubiferous, tubes uniformly arranged in single row; interlaminate figures simple; basis calcareous or membranous; when membranous, wall solid.

Comment: Jones (2000), based on morphology, classified Hexelasma Hoek, 1913 and Bathylasma Newman & Ross, 1971 under Pachylasmatoidea. Based on molecular evidence, Chan et al. (2017a) showed that the clade containing Hexelasma and Bathylasma is sister to Tetraclitidae in the same clade. This suggests that Bathylasmatidae should be treated as an individual family and included in Coronuloidea .