sp. nov. and sp. nov., two novel species closely related to the zoonotic , isolated from black rats and wild desert rodent-fleas.

The genus (Family: ; Order: Class: Alphaproteobacteria) comprises facultative intracellular Gram-negative, haemotropic, slow-growing, vector-borne bacteria. Wild rodents and their fleas harbor a great diversity of species and strains of the genus , including several zoonotic ones. This genetic diversity coupled with a fastidious nature of the organism results in a taxonomic challenge that has led to a massive collection of uncharacterized strains. Here, we report the genomic and phenotypic characterization of two strains, members of the genus (namely Tel Aviv and OE 1-1), isolated from rats and fleas, respectively. Scanning electron microscopy revealed rod-shaped bacteria with polar pili, lengths ranging from 1.0 to 2.0 µm and widths ranging from 0.3 to 0.6 µm. OE 1-1 and Tel Aviv strains contained one single chromosome of 2.16 and 2.23 Mbp and one plasmid of 29.0 and 41.5 Kbp, with average DNA G+C contents of 38.16 and 38.47 mol%, respectively. These strains presented an average nucleotide identity (ANI) of 89.9 %. was found to be the closest phylogenetic relative of both strains (ANI=90.9-93.6 %). The major fatty acids identified in both strains were Cω7, C and C. They differ from in their C and C compositions. Both strains are strictly capnophilic and their biochemical profiles resembled those of species of the genus with validly published names, whereas differences in arylamidase activities partially assisted in their speciation. Genomic and phenotypic differences demonstrate that OE 1-1 and Tel Aviv strains represent novel individual species, closely related to , for which we propose the names sp. nov. and sp. nov.