Phylum Brachiopoda Duméril, 1806 - brachiopods Subphylum Rhynchonelliformea Williams et al., 1996 Class †Strophomenata Williams et al, 1996 Order †Billingsellida Schuchert, 1893 1 Suborder †Billingsellidina Schuchert, 1893 2 Suborder †Clitambonitidina Opik, 1934