Phylum Brachiopoda Duméril, 1806 - brachiopods
   Subphylum Rhynchonelliformea Williams et al., 1996
     Class Rhynchonellata Williams et al., 1996
       Order †Athyridida Boucot et al., 1964
         Suborder †Retziidina Boucot et al., 1964
           Superfamily †Rhynchospirinoidea Schuchert, 1929
             Family †Parazygidae Alvarez et al., 1998