[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Phylum Annelida Lamarck, 1809 - segmented worms
     Class Polychaeta Grube, 1850 - polychaetes
       Family Capitellidae Grube, 1862
         Genus Mediomastus Hartman, 1944
           1 Mediomastus capensis Day, 1961
           2 Mediomastus cirripes Ben-Eliahu, 1976
           3 Mediomastus fragilis Rasmussen, 1973