Mycoplasmataceae

In 1967, the order Mycoplasmatales was incorporated into the class Mollicutes. Sexually transmitted species and Ureaplasma are classified in Mycoplasmoidaceae since 2018.

Taxonomy

Mycoplasma

Mycoplasma is a genus of bacteria that lack a cell wall and possess a three-layered cellular membrane. They can be parasitic or saprotrophic.

Several species formerly classified as Mycoplasma are sexually transmitted and pathogenic in humans (see Mollicutes § Species which infect humans). Others are found on cats, dogs, and barnyard fowl.

Taxa infecting insects

A few genera infecting insects were added to this family in 2019 using molecular phylogenetic evidence. These genera were originally called Entomoplasmataceae and believed to be monophyletic. However, work in 2019 found it to be a paraphyletic group by the exclusion of Mycoplasma. The two original genera (Mesoplasma and Entomoplasma) were also found to be in need of breaking up due to polyphyly. As a result five genera were finally added:

• Mesoplasma (formerly "Mesoplasma clade I")
• Entomoplasma (formerly "Entomoplasma clade I")
• Tullyiplasma (formerly "Mesoplasma clade II")
• Williamsoniiplasma (formerly "Entomoplasma clade II")
• Edwardiiplasma (formerly "Mesoplasma clade III")