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The identification and phylogenetic relationships of bacteria within the Bacillus cereus group are controversial,and therefore,this study aimed to determine the taxonomic affiliations of these strains using the whole-genome sequence-based Genome BLAST Distance Phylogeny(GBDP)approach.The GBDP analysis clearly separated 224 strains into 30 clusters representing eleven known partially merged species and accordingly 19-20 putative novel species.Based on the GBDP results,further analyses were performed on 16S rRNA gene,a novel variant of multi-locus sequence analysis(nMLSA)and screening of virulence genes.The 16S rRNA gene sequence was not sufficient to differentiate the bacteria within this group due to its high conservation.The nMLSA results were consistent with that of GBDP.Moreover,a fast typing method could be proposed using the pycA gene and where necessary the ccpA gene.The pXO plasmids and cry genes were widely distributed,albeitvague tendencies,suggesting that they have little correlation with the phylogenetic positions of the host bacteria.In summary,this is the first large-scale and systematic study of the taxonomic starus of the bacteria within the B.cereus group using whole-genome sequences,and is likely to contribute to further insights into their pathogenicity,phylogeny and adaptation to diverse environments.