thermosipho thermosipho thermosipho is a genus of gram-negative staining, anaerobic, and mostly thermophilic and hyperthermophilic bacteria in the family thermotogaceae. thermosipho scientific classification domain: bacteria phylum: thermotogota class: thermotogae order: thermotogales family: thermotogaceae genus: thermosiphohuber, woese, langworthy, fricke & stetter, 1989 species thermosipho africanus (huber, woese, langworthy, fricke & stetter) emend. ravot, ollivier, patel, magot & garcia, 1996 thermosipho atlanticus urios, cueff-gauchard, pignet, postec, fardeau, ollivier & barbier, 2004 thermosipho japonicus takai & horikoshi, 2000 thermosipho melanesiensis antoine, cilia, meunier, guezennec, lesongeur & barbier, 1997