Two Gram-positive bacterial strains, CM2104(T) and CM2110, isolated from the inner part of abnormally spoiled oriental melon (Cucumis melo) in Korea, were subjected to a polyphasic taxonomic study. The cell-wall peptidoglycan of strains CM2104(T) and CM2110 contained meso-diaminopimelic acid as the diagnostic diamino acid. The predominant menaquinone was MK-8(H(4)). The major fatty acids detected in the two strains were iso-C(16 : 0), C(17 : 1)omega8c and C(18 : 1)omega9c or C(17 : 0). The DNA G+C content of the two strains was 73 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains formed a coherent cluster with a clade comprising two Janibacter species, Janibacter limosus and Janibacter terrae. Strains CM2104(T) and CM2110 exhibited a 16S rRNA gene sequence similarity value of 99.7 % and a mean DNA-DNA relatedness level of 89 %. Strains CM2104(T) and CM2110 showed 16S rRNA gene sequence similarity levels of 97.8-98.4 % to the type strains of J. limosus and J. terrae. DNA-DNA relatedness between strains CM2104(T) and CM2110 and the type strains of these two Janibacter species was 7-11 %. On the basis of the phenotypic and phylogenetic data and genomic distinctiveness, strains CM2104(T) and CM2110 should be placed within the genus Janibacter as members of a novel species, for which the name Janibacter melonis sp. nov. is proposed. The type strain is CM2104(T) (=KCTC 9987(T)=DSM 16063(T)=JCM 12321(T)).