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The taxonomic position of an actinomycete, strain K07-23(T), isolated from a cold desert of the Himalayas, India, was established by a polyphasic approach. The strain exhibited phenotypic characters that were typical of the genus Rhodococcus. 16S rRNA gene sequence (11467 bases) comparisons confirmed that strain K07-23(T) belongs to the genus Rhodococcus. 16S rRNA sequence similarity studies showed that the isolate is very closely related to Nocardia corynebacterioides DSM 20151(T) (98-6%), which has been recently reclassified as Rhodococcus corynebacterioides. It showed 94(.)4-96(.)6% sequence similarity with other species of the genus Rhodococcus. However, genomic relatedness between strain K07-23(T) and R. corynebacterioides as revealed by DNA-DNA hybridization was low (62%). Based on polyphasic analysis, strain K07-23 T could be clearly distinguished from other species. It is proposed that strain K07-23(T) (= MTCC 6634(T) = DSM 44908(T)=jCM 13011(T)) represents a novel species of Rhodococcus, Rhodococcus kroppenstedtii sp. nov.