II. Taxonomy
- Class: Mollicutes
- Order: Mycoplasmatales
- Family: Mycoplasmataceae
III. Genus I: Mycoplasma (60 species, do not hydrolyze urea)
- Mycoplasma pneumoniae
- Mycoplasma hominis
IV. Genus II: Ureaplasma (2 species, hydrolyze urea)
- Ureaplasma urealyticum