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A polyphasic study was undertaken to establish the taxonomic status of three representative Geodermatophilus strains isolated from an extreme hyper-arid Atacama Desert soil. The strains, isolates B12(T), B20 and B25, were found to have chemotaxonomic and morphological properties characteristic of the genus Geodermatophilus. The isolates shared a broad range of chemotaxonomic, cultural and physiological features, formed a well-supported branch in the Geodermatophilus 16S rRNA gene tree in which they were most closely associated with the type strain of Geodermatophilus obscurus. They were distinguished from the latter by BOX-PCR fingerprint patterns and by chemotaxonomic and other phenotypic properties. Average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between the whole genome sequences of isolate B12(T) and G. obscurus DSM 43160(T) were 89.28%, 87.27% and 37.4%, respectively, metrics consistent with its classification as a separate species. On the basis of these data, it is proposed that the isolates be assigned to the genus Geodermatophilus as Geodermatophilus chilensis sp. nov. with isolate B12(T) (CECT 9483(T) =NCIMB 15089(T)) as the type strain. Analysis of the whole genome sequence of G. chilensis B12(T) with 5341 open reading frames and a genome size of 5.5 Mb highlighted genes and gene clusters that encode for properties relevant to its adaptation to extreme environmental conditions prevalent in extreme hyper-arid Atacama Desert soils. (C) 2018 Published by Elsevier GmbH.