parvibacter parvibacter parvibacter is a genus in the phylum actinomycetota containing a single species, parvibacter caecicola. parvibacter scientific classification domain: bacteria phylum: actinomycetota class: coriobacteriia order: eggerthellales family: eggerthellaceae genus: parvibacterclavel et al. 2013 species: p. caecicola binomial name parvibacter caecicolaclavel et al. 2013 taxonomy in 2018, nouioui et al. proposed merging the genus parvibacter along with the genera asaccharobacter and enterorhabdus within the genus aldercreutzia based on observed clustering of these genera within phylogenetic trees. however, subsequent phylogenetic analyses observed that parvibacter caecicola exhibited much deeper branching compared to other aldercreutzia species. its phylogenetic distinctness was further demonstrated by the presence of five conserved signature indels (csis) that are exclusively shared by all aldercreutzia species except for p. caecicola. thus, p. caecicola was transferred back into the genus parvibacter, which continues to be a validly published genus.