The Staphylococcus genus includes at least 40 species. Of these, nine have two subspecies, one has three subspecies, and one has four subspecies. Most are harmless and normally reside on the skin and mucous membranes of humans and other organisms. Found worldwide, they are a small component of soil microbial flora.
Staphylococcus species can be differentiated from other aerobic and facultative anaerobic, Gram-positive cocci by several simple tests. Staphylococcus species are facultative anaerobes (capable of growth both aerobically and anaerobically). All species grow in the presence of bile salts.
