Genus Actinomyces refers to a group of gram-positive, anaerobic bacteria that are commonly found in soil and oral cavities of humans and animals. These bacteria are known to cause opportunistic infections, particularly in immunocompromised individuals. There are several synonyms for Genus Actinomyces, including Actinobaculum, Actinomycesidae, and Actinomycinea. These bacteria are often associated with the formation of abscesses, especially in the mouth and jaw. In addition, Actinomyces species are known to be involved in the deterioration of teeth and dental fillings. Although not typically harmful, infections caused by these bacteria can be serious and require immediate treatment.