%0 Journal Article %A Kato, Shingo %A Ohnishi, Masafumi %A Nagamori, Mai %A Yuki, Masahiro %A Takashina, Tomonori %A Ohkuma, Moriya %A Itoh, Takashi %T Conexivisphaera calida gen. nov., sp. nov., a thermophilic sulfur- and iron-reducing archaeon, and proposal of Conexivisphaeraceae fam. nov., Conexivisphaerales ord. nov., and Conexivisphaeria class. nov. in the phylum Thaumarchaeota %D 2020 %J International Journal of Systematic and Evolutionary Microbiology, %V 71 %N 1 %@ 1466-5034 %C 004595 %R https://doi.org/10.1099/ijsem.0.004595 %K terrestrial hot spring %K thermophile %K archaea %K Thaumarchaeota %I Microbiology Society, %X A thermoacidophilic, anaerobic, and iron- and sulfur-reducing archaeon, strain NAS-02T, was isolated from a terrestrial hot spring in Japan, as previously reported. This organism is the first non-ammonia-oxidizing isolate in the phylum Thaumarchaeota . Here, we propose Conexivisphaera calida gen. nov., sp. nov. to accommodate this strain. The type strain of the type species is NAS-02T (=JCM 31663T=DSM 105898T). The values of 16S rRNA gene similarity and average amino acid identity between NAS-02T and its closest relatives are <86 and <42 %, respectively. Based on the phylogeny and physiology, we propose the family Conexivisphaeraceae fam. nov., the order Conexivisphaerales ord. nov. and the class Conexivisphaeria class. nov. to accommodate the novel genus. %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.004595