procaryotes
   Domain Archaea Woese et al. 1990
     Phylum Euryarchaeota Garrity and Holt 2001
       Class Methanococci Boone 2001 nom. inval. see Class Methanococci Boone 2002
         Order Methanosarcinales Boone et al. 2001 nom. inval. see Order Methanosarcinales Boone et al. 2002
           Family Methanosarcinaceae Balch and Wolfe 1981
             1 Genus Methanosarcina Kluyver and van Niel 1936 (Approved Lists 1980)
             2 Genus Methanococcoides Sowers and Ferry 1985
             3 Genus Methanohalobium Zhilina and Zavarzin 1988
             4 Genus Methanohalophilus Paterek and Smith 1988
             5 Genus Methanolobus König and Stetter 1983
             6 Genus Methanosalsum Boone & Baker 2001 nom. inval. see Genus Methanosalsum Boone and Baker 2002