A novel actinobacterium designated as MSL-26(T) was isolated from soil in Bigeum Island Korea. A polyphasic study was undertaken to establish the taxonomic position of isolate MSL-26(T). Strain MSL-26(T) was found to have chemical and morphological characteristics similar to Nocardioides. The strain grew optimally at pH 7.5 and 28 degrees C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MSL-26(T) forms a distinct line of descent within the radiation enclosed by the genus Nocardioides. The cell wall of strain MSL-26(T) contained LL-2, 6-diaminopimelic acid. The principal menaquinone was MK-8 (H(4)). The phospholipids detected were diphosphatidylglycerol, phosphatidylglycerol and some unidentified lipids. C(18:1) w7c (50.38%) was the major fatty acid. The DNA G + C content of strain MSL-26(T) was 71.4 mol%. The 16S rRNA gene sequence of strain MSL-26(T) shares the highest sequence similarity with Nocardioides kribbensis KCTC 19038(T) (95.78%) and Nocardioides aquaticus DSM 11439(T) (95.52%). Based on the morphological, physiological, biochemical and chemotaxonomical data presented in this study, strain MSL-26(T) should be classified as a novel species, for which the name Nocardioides islandiensis sp. nov. is proposed. The type strain is MSL-26(T) (=KCTC 19275(T)=DSM 19321(T)).