A short coccoid-or rod-shaped, non-motile actinomycete strain RC825 T was isolated from lichen in Izu-Oshima Island, Japan. A polyphasic study was undertaken to establish the taxonomic position of this strain. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain RC825 T forms an evolutionary lineage within the radiation of the genus Nocardioides. In particular, it forms a coherent cluster with Nocardioides oleivorans and Nocardioides ganghwensis with high sequence

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... y of 98 and 97.5%, respectively. However, DNA-DNA hybridization experiment demonstrated that strain RC825 T is distinct from its closest phylogenetic neighbors, N. oleivorans and N. ganghwensis, with 44 and 39% relatedness, respectively. The cell-wall peptidoglycan of strain RC825 T contained LL-diaminopimelic acid, indicating wall chemotype I. The predominant menaquinone was MK-8(H 4 ). Strain RC825 T had a cellular fatty acid profile containing straight-chain, branched, unsaturated and 10-methyl fatty acids, and the major fatty acid was iso-C 16:0 . The DNA G+C content of the strain was 74 mol%. On the basis of both phenotypic and phylogenetic evidence, the strain is separated from previously described Nocardioides species, and should be assigned to represent a novel species of the genus Nocardioides, for which the name Nocardioides exalbidus sp. nov. is proposed. The type strain is strain RC825 T (=IAM 15416 T =CCTCC AA206016 T ).