A non-motile and non-endospore-forming rod, strain NBRC 16403T, was isolated from the phyllosphere of a sedge (Carex sp.). 16S rRNA gene sequence analysis indicated that strain NBRC 16403T was closely related to Herbiconiux solani DSM 19813T (98.6 % 16S rRNA gene sequence similarity), Herbiconiux ginsengi wged11T (97.8 %) and Herbiconiux moechotypicola RB-62T (97.8 %). The peptidoglycan (B2γ type) contained D- and l-2,4-diaminobutyric acids, d-alanine, glycine and threo-3-hydroxyglutamic acid, which replaced glutamic acid almost completely. The predominant menaquinones were MK-10 and MK-11. The polar lipid pattern comprised diphosphatidylglycerol, phosphatidylglycerol, three glycolipids and minor amounts of other polar lipids. The major fatty acids were anteiso-C15:0, iso-C16:0 and anteiso-C17:0; no cyclohexyl-C17:0 was detected. The DNA G+C content was 71.0 mol%. The results of phylogenetic and DNA-DNA relatedness studies, along with phenotypic differences between strain NBRC 16403T and recognized members of the genus Herbiconiux, indicated that the isolate should be assigned to a novel species of the genus Herbiconiux, for which the name Herbiconiux flava sp. nov. is proposed. The type strain is NBRC 16403T (=VKM Ac-2058T).