This species is known to be heterogeneous with micro-variation among 16S rRNA sequences, including between operons within strains and phenotypic variation including colonial appearance [1].

Colonies on horse blood agar are around 1 mm in diameter, circular, entire, opaque white or translucent gray and may be smooth or rough after 4 days anaerobic incubation.

Small (0.3 -0.7 micron diameter) Gram-positive cocci occurring in pairs and short chains [2]. Obligate anaerobe. Strains are asaccharolytic and the end-products of metabolism are primarily acetate with small amounts of lactate and sometimes succinate produced. The mol % G+C content of the DNA is 27-28.

Parvimonas micra is a commonly found oral species and is isolated from dental plaque and the tongue in health and a variety of oral disease associated microbiota including periodontitis, endodontic and dentoalveolar infections, pericoronitis and advanced dental caries.

Has been isolated from most types of oral infection. Is a particularly frequent isolate from acute dentoalveolar infections where it is often a member of the 15-20 species consortium associated with the condition. Has also been isolated from clinical specimens obtained from infections at other body sites, primarily soft-tissue abscesses and bite wounds. These are primarily at sites above the diaphragm suggesting that the mouth is the primary habitat.