[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain Bacteria Woese et al. 1990
     Phylum "Proteobacteria" Garrity et al. 2005 see Superphylum Proteobacteria Craig et al. 2010
       Class Gammaproteobacteria Garrity et al. 2005
         Order Methylococcales Bowman 2005
           Family Methylococcaceae Whittenbury and Krieg 1984
             Genus Methylomonas (ex Leadbetter 1974) Whittenbury and Krieg 1984
               1 Methylomonas methanica (ex Söhngen 1906) Whittenbury and Krieg 1984
               2 Methylomonas aurantiaca Bowman et al. 1990
               3 Methylomonas fodinarum Bowman et al. 1990
               4 Methylomonas scandinavica Kalyuzhnaya et al. 2000