Biochemical, chemotaxonomic, and molecular methods were used to establish the precise taxonomic position of the Centers for Disease Control (CDC) coryneform group 2 bacteria. The results of a comparative 16S rRNA sequence analysis demonstrated that the CDC coryneform group 2 bacteria constitute a distinct species within the genus Actinomyces. Actinomyces pyogenes was found to be the closest genealogical relative of the CDC coryneform group 2 bacteria, although these taxa were readily distinguished from each other and other Actinomyces spp. by using phenotypic criteria. On the basis of our findings we propose the name Actinomyces bernardiae sp. nov. for the CDC coryneform group 2 bacteria. The type strain is DSM 9152 (CCUG 33419).