methanomicrobiales methanomicrobiales in the taxonomy of microorganisms, the methanomicrobiales are an order of the methanomicrobia. methanomicrobiales are strictly carbon dioxide reducing methanogens, using hydrogen or formate as the reducing agent. as seen from the phylogenetic tree based on 'the all-species living tree' project the family methanomicrobiaceae is highly polyphyletic within the methanomicrobiales. methanomicrobiales scientific classification domain: archaea kingdom: euryarchaeota class: methanomicrobia order: methanomicrobialesbalch and wolfe 1981 families methanocalculaceae methanocorpusculaceae "methanoculleaceae" methanospirillaceae methanomicrobiaceae methanoregulaceae "methanosphaerulaceae" phylogeny the currently accepted taxonomy is based on the list of prokaryotic names with standing in nomenclature (lpsn) and national center for biotechnology information (ncbi). 16s rrna-based ltp_01_2022 53 marker proteins based gtdb 07-rs207 methanomicrobiaceae (incl. "methanoculleaceae") "methanosphaerulaceae" methanolinea tarda methanolinea mesophila methanoregulaceae methanospirillaceae "methanofollaceae" methanocalculaceae zhilina et al. 2014 methanocorpusculaceae methanocorpusculaceae zellner et al. 1989 (incl. methanocalculaceae) "methanofollaceae" "methanosphaerulaceae" rinke et al. 2020 methanospirillaceae boone et al. 2002 methanoregulaceae sakai et al. 2012 "methanoculleaceae" rinke et al. 2020 methanomicrobiaceae balch & wolfe 1981