Genome-based reclassification of Micromonospora veneta Kaewkla et al. 2022 as a later heterotypic synonym of Micromonospora coerulea Jensen 1932 (Approved lists 1980).

In this study, we aimed to clarify the taxonomic positions of Micromonospora veneta DSM 109713 and Micromonospora coerulea JCM 3175 using whole-genome phylogenetic analysis, pangenomic analysis and chemotaxonomic characteristics. The 16S rRNA gene sequences of veneta DSM 109713 and M. coerulea JCM 3175 were highly similar (99.2%), and in the phylogenetic trees constructed using whole genome sequences and 16S rRNA gene sequences, M. veneta DSM 109713 and M. coerulea JCM 3175 clustered together and formed a clade. The values of average amino acid (AAI), ANI-BLAST (ANIb) and ANI-MUMmer (ANIm), and digital DNA-DNA hybridization (dDDH) between M. veneta DSM 109713 and M. coerulea JCM 3175 were 97.57%, 97.81%, 98.40%, 85.0%, respectively, which are all greater than the thresholds used for species delimitation (AAI: 95.5%, ANI: 95-96%, and dDDH: 70%). Most phenotypic and chemotaxonomic features between the two species were similar, with only a few differences. Based on the combined evidence from genomic and phenotypic comparison, we propose Micromonospora veneta as a later heterotypic synonym of Micromonospora coerulea.