runella runella runella is a gram-negative, aerobic and non-motile bacterial genus from the family spirosomaceae. runella scientific classification domain: bacteria phylum: bacteroidota class: cytophagia order: cytophagales family: spirosomaceae genus: runellalarkin and williams 1978 type species runella slithyformis species r. defluvii r. limosa r. slithyformis r. zeae