A species of Gram-negative, facultatively anaerobic spherical or rod-shaped bacteria indigenous to dental surfaces. It is associated with PERIODONTITIS; BACTERIAL ENDOCARDITIS; and ACTINOMYCOSIS.

Synonyms: Aggregatibacter actinomycetemcomitans, Bacterium comitans, txid714, Actinobacillus actinomycetemcomitans, Haemophilus actinomyceticomitans, Bacterium acetinomycetum comitans, Haemophilus actinomycetemcomitans