compostibacillus compostibacillus compostibacillus is a gram-positive, moderately thermophilic rod-shaped, and spore-forming genus of bacteria from the family of bacillaceae with one known species (compostibacillus humi). compostibacillus humi has been isolated from sludge compost from guangdong in china. compostibacillus scientific classification domain: bacteria phylum: bacillota class: bacilli order: bacillales family: bacillaceae genus: compostibacillusyu et al. 2015 species c. humi