Actinomycosis

Actinomycosis are "infections with bacteria of the genus actinomyces." Actinomyces is a "genus of gram-positive, rod-shaped bacteria whose organisms are nonmotile. Filaments that may be present in certain species are either straight or wavy and may have swollen or clubbed heads."

Ecology
"Actinomyces are commensals of the human oropharynx, gastrointestinal tract, and urogenital tract."