Reclassification of Sphingomonas aeria as a later heterotypic synonym of Sphingomonas carotinifaciens based on whole-genome sequence analysis

The 16S rRNA gene sequences of L9-754 and B093034 possess 99.71 % sequence similarity. Further studies were undertaken to clarify the taxonomic assignments of these species. Whole-genome comparisons showed that B093034 and L9-754 shared 96.9 % average nucleotide identity, 98.4 % average amino acid identity and 76.1 % digital DNA-DNA hybridization values. These values exceeded or approached the recommended species delineation threshold values. Furthermore, a phylogenetic tree based on 41 of the most conserved genes provided additional evidence that B093034 and L9-754 are very closely related. Based on this evidence we propose the reclassification of Xue . 2018 as a later heterotypic synonym of Madhaiyan . 2017.