Phylum Brachiopoda Duméril, 1806 - brachiopods
   Subphylum Rhynchonelliformea Williams et al., 1996
     Class Rhynchonellata Williams et al., 1996
       Order †Protorthida Schuchert & Cooper, 1931
         1 Superfamily †Protorthoidea Schuchert & Cooper, 1931
         2 Superfamily †Skenidioidea Kozlowski, 1929