Phylogenetic tree highlighting the position of M. petrolearius SEBR 4847T relative to the other type strains within the order Methanomicrobiales. The tree was inferred from 1,275 aligned characters [4,5] of the 16S rRNA gene sequence under the maximum likelihood criterion  and rooted with Methanocellales . The branches are scaled in terms of the expected number of substitutions per site. Numbers above branches are support values from 350 bootstrap replicates  if larger than 60%. Lineages with type strain genome sequencing projects registered in GOLD  are shown in blue, published genomes in bold [10,11] and GenBank accessions CP001338 (for Methanosphaera palustris E1-9c) and AP011532 (for Methanocella paludicola).