Taxonomic revision of the family Aurantimonadaceae: proposal of Dennerimonas gen. nov., Mesocryomonas gen. nov., Rathsackimonas gen. nov. and Plantimonas gen. nov., along with the reclassification of Jeongeupella Jiang et al. 2024 as a later heterotypic synonym of Antarcticirhabdus Du et al. 2023
Phylogenetic analysis of the genus Aureimonas, utilizing both 16S rRNA gene sequences and comprehensive whole-genome data, revealed its polyphyletic nature, necessitating a revision to accommodate phylogenetically distinct species. Based on established threshold values for genus demarcation – specifically, 16S rRNA gene similarity, Average Amino Acid Identity and Percentage of Conserved Proteins – a notably substantial divergence was observed within the genus Aureimonas, and the division of Aureimonas into four distinct genera is strongly supported. To address this, we propose the establishment of four new genera: Dennerimonas gen. nov., Mesocryomonas gen. nov., Rathsackimonas gen. nov. and Plantimonas gen. nov. These classifications accommodate species that are significantly divergent from the type species of Aureimonas, thereby more accurately reflecting their distinct evolutionary lineages. Additionally, Aureimonas glaciistagni is proposed to be reclassified within the genus Jiella as Jiella glaciistagni comb. nov. based on phylogenetic evidence indicating a closer evolutionary relationship to Jiella species than to other members of Aureimonas. Our analysis, which included assessments of 16S rRNA gene similarity, Average Nucleotide Identity, and digital DNA–DNA hybridization values exceeding species delineation thresholds, further supports the reclassification of Jeongeupella Jiang et al. 2024 as a later heterotypic synonym of Antarcticirhabdus Du et al. 2023.