The genus , created by the reclassification of specific deep-branching species, exhibits polyphyletic branching. The Genome Taxonomy Database (GTDB) also assigns species into two families and three genera. To clarify the evolutionary relationships and classification of species, we report detailed investigations using phylogenomic and molecular signature-based approaches. In phylogenomic trees, species are distributed within two family-level lineages. One of these clades, containing the type species (viz. ), represents the genus , groups within the family . Ten novel conserved signature indels (CSIs) identified in this study are specific for this clade, providing a robust means for the differentiation of the emended genus . The remaining species form a separate family-level clade, designated as f_HBI72195 in the GTDB. Within this clade, all species except form a robust clade designated as clade -2 in our work and g__A in the GTDB. We have also identified 15 novel CSIs specific to this clade. As the clade -2 is distinct from , we propose transferring species from this clade into a new genus, gen. nov. The species branches distinctly from other species, and the GTDB considers it a novel genus (g_BR). Six newly identified CSIs are specific to this species, and we are proposing the transfer of this species into a new genus, gen. nov. Two additional identified CSIs are shared by members of the novel family-level taxon (f_HBI72195) comprising the proposed genera and , for which we are proposing the name fam. nov. Lastly, the results presented here also show that '' and '' are later heterotypic synonyms of . These changes, which reliably depict the evolutionary relationships among species, should be helpful in future studies of these organisms.