A novel Gram-reaction-positive bacterium, strain CH22-21(T), was isolated from a water sample taken from Daechung Reservoir, Republic of Korea, during the late-blooming period of cyanobacteria. Cells of strain CH22-21(T) were non-motile, ciliated short rods that formed creamy-white colonies on half-strength modified R2A agar. Chemotaxonomic results showed menaquinone MK-9(H6) as the predominant respiratory menaquinone, diphosphatidylglycerol, phosphatidylinositol and phosphatidylinositolmannoside as major polar lipids, 16 : 1ω5c, 16 : 0, 17 : 1ω8c and 18 : 1ω9c as major fatty acids, and a DNA G+C content of 71.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain formed a separate lineage within the order Acidimicrobiales, showing similarity values of <92.3 % with its closest phylogenetic neighbours. The combined genotypic and phenotypic data showed that strain CH22-21(T) could be distinguished from all genera within the order Acidimicrobiales and represented a novel species of a new genus in the family Iamiaceae, for which the name Aquihabitans dachungensis gen. nov., sp. nov. is proposed. The type strain of Aquihabitans dachungensis is CH22-21(T) (= KCTC 19849(T) = JCM 17787(T)).