Phylum [Mollusca] Linnaeus, 1758 - molluscs
   Class Bivalvia Linnaeus, 1758 - bivalves
     Order Veneroida H. & A. Adams, 1856 see Order Venerida Gray, 1854
       Superfamily Cardiacea Lamarck, 1809 see Superfamily Cardioidea Lamarck, 1809
         Family Cardiidae Lamarck, 1809 - cockles
           Subfamily Trachycardiinae Stewart, 1930
             Genus Trachycardium Mörch, 1853
               Subgenus Trachycardium (Trachycardium) Mörch, 1853