Phylum Brachiopoda Duméril, 1806 - brachiopods Subphylum Rhynchonelliformea Williams et al., 1996 Class Rhynchonellata Williams et al., 1996 Order †Athyridida Boucot et al., 1964 Suborder †Athyrididina Boucot et al., 1964 Superfamily †Retzielloidea Rzhonsnitskaya, 1974 1 Family †Retziellidae Rzhonsnitskaya, 1974