A Gram-positive, aerobic organism, showing an irregular cell morphology was isolated from the root tissue of cucumber (Cucumis sativus) and investigated in detail for its taxonomic position. On the basis of the 16S rRNA gene sequence analysis strain AP-38T was shown to be most closely related to Isoptericola variablis (99.1%), and Isoptericola nanjingensis (98.9%). The 16S rRNA gene sequence similarity to all other Isoptericola species was ≤ 98.5 %. DNA-DNA similarities to Isoptericola variablis DSM 10177T and Isoptericola nanjingensis DSM 24300T were 31%/41% (reciprocal) and 34%/34% (reciprocal), respectively. The diagnostic diaminoacid of the peptidoglycan was L-lysine.The quinone system contained predominantly menaquinones MK-9(H4) and MK-9(H2). In the polar lipid profile major compounds were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two phosphatidylinositol-mannosides. The polyamine pattern contained the major components spermidine and spermine and significant amounts of tyramine. In the fatty acid profile, anteiso-C15:0, and iso C15:0 were present in major amounts. These data support the allocation of the strain to the genus Isoptericola. The results of physiological and biochemical characterization additionally provides a phenotypic differentiation of strain AP-38T from N. variabilis and N. nanjingensis. AP-38T represents a new species of the genus Isoptericola, for which we propose the name Isoptericola cucumis sp. nov., with AP-38T (= LMG 29223T = CCM = 8653T) as the type strain.