Moraxella

The genus Moraxella belongs to the family Moraxellaceae, which includes the closely related genera Acinetobacter and Psychrobacter. The Moraxella genus itself currently contains 15 different species, including M. lacunata, M. atlantae, M. boevrei, M. bovis, M. canis, M. caprae, M. catarrhalis, M. caviae, M. cuniculi, M. equi, M. lincolnii, M. nonliquefaciens, M. osloensis, M. ovis, and M. saccharolytica. Recently, M. pluranimalium has been described as a new species of the genus Moraxella, after its isolation from sheep and pigs. Although all of these 15 species have been classified within the genus Moraxella, the classification of the Moraxellaceae family is still not definitive but continuously evolving. For example, molecular systematic studies (of which 16S ribosomal RNA (rRNA) gene sequencing has long been the "gold standard") has led to the reclassification of Riemerella anatipestifer, Psychrobacter phenylpyruvicus, and Oligella urethralis, which were formally known as Moraxella anatipestifer, Moraxella phenylpyruvica, and Moraxella urethralis, respectively.