 In the Cavalier-Smith bacterial megaclassification, it is within the bacterial Gracilicutes infra-kingdom and comprises the phyla Chlamydiae, Lentisphaerae, Planctomycetes, Verrucomicrobia.Planctomycetes, Verrucomicrobia, and Chlamydiae in the traditional molecular phylogeny view are considered as phyla and also cluster together in what is referred to as the PVC superphylum, along with the candidate phyla Omnitrophica (previously OP3) and the Poribacteria.An important molecular marker in the form of a conserved signature protein has been found to be consistently shared by PVC members, with the exception of Poribacteria.