A Gram-negative, rod-shaped bacterium (CC-JY-1(T)) was isolated on nutrient agar from a soil sample collected from an oil-contaminated site located in Chyai county, Taiwan. 16S rRNA gene sequence analysis demonstrated that this isolate is unique, showing 96.7 % sequence similarity to the type strain of Arenimonas donghaensis and similarities of 93.0-93.8 % to species of the genera Thermomonas, Lysobacter and Silanimonas. The presence of ubiquinone Q-8, a polar lipid profile consisting of the major compounds diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine and the fatty acid profile were in accordance with the phylogenetic affiliation of CC-JY-1(T). DNA-DNA reassociation experiments between CC-JY-1(T) and A. donghaensis KACC 11381(T) resulted in a mean relatedness value of 32 %, indicating that strain CC-JY1(T) represents a novel species in the genus Arenimonas, for which we propose the name Arenimonas malthae sp. nov. The type strain is CC-JY-1(T) (=CCUG 53596(T) =CIP 109310(T)).