Phylogenetic tree highlighting the position of M. fervidus V24ST relative to the other type strains within the family Methanothermaceae. The tree was inferred from 1,249 aligned characters [3,4] of the 16S rRNA gene sequence under the maximum likelihood criterion  and rooted in accordance with the current taxonomy . The branches are scaled in terms of the expected number of substitutions per site. Numbers above branches are *support values from 100 bootstrap replicates  if larger than 60%. Lineages with type strain genome sequencing projects registered in GOLD  are shown in blue, published genomes in bold [9–12].