A Dyella-like bacterium was previously isolated from the planthopper Hyalesthes obsoletus (Hemiptera). Based on its 16S rRNA gene sequence, strain DHo T was assigned to the family Rhodanobacteraceae with Dyella and Frateuria as its closest relatives. The closest 16S rRNA gene sequences were Frateuria aurantia DSM 6220 T (98.2 %), Dyella thiooxydans ATSB10 T (98 %), Dyella terrae JS14-6 T (97.8 %) and Dyella marensis CS5-B2 T (97.8 %). Strain DHo T is a Gram-negative, aerobic, motile, yellow-pigmented, rod-shaped bacterium. Strain DHo T cells grew well at 28-30 C and at pH 6.5-7.5 on a nutrient agar plate. DNA-DNA hybridization showed that the relatedness between strain DHo T and D. jiangningensis strain SBZ3-12 T , and F. aurantia DSM 6220 T was 42.7 and 42.6 %, respectively. Ubiquinone Q-8 was the predominant respiratory quinone, and the major fatty acids (>10 %) were iso-C 15 : 0 , iso-C 16 : 0 and iso-C 17 : 0. In silico analysis based on phylogenetics and sequence identity at the nucleotide and protein levels suggests that Frateuria is the closest known relative of strain DHo T. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain DHo T was designated as a novel species of the genus Frateuria, for which the name Frateuria defendens sp. nov. is proposed. The type strain is DHo T