"Candidatus Methanosphaerula" Cadillo-Quiroz et al. 2008 Dataset NCBI Taxonomy Classification phylum Euryarchaeota class Methanomicrobia order Methanomicrobiales family Methanoregulaceae genus Methanosphaerula Name Homonyms Candidatus Methanosphaerula "Candidatus Methanosphaerula" Cadillo-Quiroz et al. 2008