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 Family †Retziellidae Rzhonsnitskaya, 1974