Abstract
The family Bacteroidaceae is emended to include bacteria that are monotrichous or lophotrichous. The genus Butyrivibrio is emended to include lophotrichous bacteria. Desulfomonas, a new genus of nonmotile, nonsporeforming, gram-negative, anaerobic, sulfate-reducing rods, and 10 new species of anaerobes, Desulfomonas pigra, Butyrivibrio crossotus, Ruminococcus gnavus, R. lactaris, R. obeum, Eubacterium dolichum, E. hadrum, E. ramulus, E. siraeum, and Clostridium leptum, are described. These species have been isolated from human intestinal contents or from human feces. The type strains of these species are ATCC 29098, 29175, 29149, 29176, 29174, 29143, 29173, 29099, 29066, and 29065, respectively.