Overview: Bacteria of the genus Veillonella are among the most abundant bacteria in the healthy mouth. They make up approximately 10% of the bacterial community on the tongue, tonsils, and throat and 2-4% in dental plaque and on the cheeks and gums.

Ecological role/importance in health and disease: Veillonella spp. consume lactate and thrive adjacent to lactate-producing streptococci (Perisamy & Kolenbrander 2010). Veillonellae such as Veillonella parvula are early colonizers of teeth; they cannot grow by themselves on saliva but they are abundant in the biofilm that forms during the first 4 hours on enamel in the mouth (Diaz et al. 2006, Periasamy and Kolenbrander 2010). Other species – V. dispar, V. rogosae, and V. atypica – are members of the tongue dorsum biofilm (Wilbert et al. 2020, Mark Welch et al. 2019). The as-yet unnamed Veillonella sp. HMT 780 is abundant on the gums. V. parvula is a member of the "purple complex" in the subgingival biofilm together with Schaalia odontolytica (Socransky et al. 1998).