gracilibacillus massiliensis gracilibacillus massiliensis gracilibacillus massiliensis is a moderately halophilic, gram-positive, non-spore-forming and motile bacterium from the genus of gracilibacillus. gracilibacillus massiliensis scientific classification domain: bacteria phylum: bacillota class: bacilli order: bacillales family: bacillaceae genus: gracilibacillus species: g. massiliensis binomial name gracilibacillus massiliensisdiop et al. 2017 type strain csur p1441, dsm 29726, train awa-1