Trichococcus species share high similarity of their 16S rRNA gene sequences (> 99%). Digital DNA-DNA hybridization values (dDDH) among all described Trichococcus species (T. flocculiformis DSM 2094T, T. pasteurii DSM 2381T, T. collinsii DSM 14526T, T. palustris DSM 9172T, and T. patagoniensis DSM 18806T) indicated that Trichococcus sp. strain R210T represents a novel species of the genus Trichococcus. The dDDH values showed a low DNA relatedness between strain R210T and all other Trichococcus spp. (23-32 %). Cells of strain R210T were motile, slightly curved rods with sizes 0.63-1.40 x 0.48-0.90 mum and stained Gram-positive. Growth was optimal at pH 7.8 and at temperature of 30 degrees C. Strain R210T could utilize several carbohydrates, and the main products from glucose fermentation are lactate, acetate, formate, and ethanol. The genomic DNA G+C content of strain R210T was 47.9%. Based on morphological, physiological, biochemical characteristics of strain R210T and along with measured dDDH values for all Trichococcus spp. we propose to separate this isolate into a new taxon on species level within Trichococcus genus. The name Trichococcus ilyis is proposed. The type strain of Trichococcus ilyis is R210T (=DSM 22150T =JCM 31247T).