L. is a pasture legume that was introduced to Australia from the Mediterranean basin in 1993. Although the native rhizobial population could not nodulate at the time of its introduction, recent research has shown the emergence of a diversity of strains (novel isolates) that are able to do so. Three novel isolates, WSM2073, WSM2074 and WSM2076, had nearly identical 16S rRNA gene sequences, and clustered separately with all recognized species of the genus . Conversely, the novel isolate WSM2075 had >23 nt mismatches with the above three isolates. All four novel isolates shared 97–99 % 16S rRNA gene sequence similarity with the type strains of all recognized species. However, strains WSM2073, WSM2074 and WSM2076 showed <95.2 % gene sequence similarity to the type strains of recognized species, and <92.9 % to WSM2075 (which also shared <95.5 % gene sequence similarity to the type strains of recognized species). Results for gene sequencing were consistent with those for the gene. The fatty acid profiles of the novel isolates were diagnostic of root-nodule bacteria, but did not match those of recognized bacterial species. Strain WSM2075 had a significantly different fatty acid profile from the other three isolates. The above results indicated that strains WSM2073, WSM2074 and WSM2076 represent the same species. Strain WSM2073 showed <45 % DNA–DNA relatedness and WSM2075 <50 % DNA–DNA relatedness with the type strains of recognized species; these two novel isolates shared 59 % DNA–DNA relatedness. Collectively, these data indicate that strains WSM2073, WSM2074 and WSM2076, and strain WSM2075 belong to two novel species of the genus , for which the names sp. nov. and sp. nov. are proposed, respectively. The type strain of sp. nov. is WSM2073 (=LMG 24608=HAMBI 3006) and the type strain of sp. nov. is WSM2075 (=LMG 24607=HAMBI 3007).


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Phenotypic characteristics that differentiate species of the genus . [PDF](75 KB)


Levels of 16S rRNA gene sequence similarity between strains WSM2073 and WSM2075 and type strains of species. [PDF](75 KB)


Neighbour-joining phylogenetic tree based on genes. [PDF](21 KB)


Neighbour-joining phylogenetic tree based on genes. [PDF](21 KB)


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