desulfacinum infernum desulfacinum infernum desulfacinum infernum is a thermophilic sulfate-reducing bacterium, the type species of its genus. its cells are oval, 1.5 by 2.5-3μm, non-motile and gram-negative. desulfacinum infernum scientific classification domain: bacteria phylum: thermodesulfobacteriota class: syntrophobacteria order: syntrophobacterales family: syntrophobacteraceae genus: desulfacinum species: d. infernum binomial name desulfacinum infernumrees et al. 1995