A Gram-negative, coccoid- or rod-shaped bacterium was isolated from black sand collected from Soesoggak beach, Jeju Island, Korea. The isolate, designated J3T, grew at 15-45 degrees C, at pH 5.5-10.0 and in 0-8 % NaCl. It was oxidase- and catalase-positive. Strain J3T reduced nitrate to nitrite, but did not reduce nitrite to nitrogen gas. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain J3T was closely related to Nitratireductor aquibiodomus NL21T and belonged to the genus Nitratireductor. Major cellular fatty acids were C(18 : 1)omega7c (82.0 %), C(19 : 0)omega8c cyclo (4.3 %) and C(18 : 0) (4.0 %), a profile that is typical of members of the genus Nitratireductor and distinct from those of other genera in the family Phyllobacteriaceae. Differences in physiological characteristics and fatty acid profiles, as well as low DNA-DNA hybridization values, further established that strain J3T was distinct from N. aquibiodomus NL21T. Thus, strain J3T (=KCTC 22119T =JCM 14935T) should be classified as the type strain of a novel species in the genus Nitratireductor, for which the name Nitratireductor basaltis sp. nov. is proposed.