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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

New names of bacterial phyla

There is a later edition (2008) of this book.

The rules for naming bacteria [International Code of Nomenclature of Prokaryotes (ICNP)] previously did not include the taxonomic category phylum, but recently (February 2021) the members of the International Committee on Systematics of Prokaryotes (ICSP) have decided that this will happen in the future. It has been decided that all names of phyla should be written in italics (which has been done on VetBact also before) and have the ending -ota. In addition, the phylum name must be based on a genus, which must constitute the nomenclature type of the phylum in question. An article by Aharon Oren and George M. Garrity entitled Valid publication of the names of forty-two phyla of prokaryotes has been published.

The new names of phyla will be entered on VetBact, but it will take some time as 277 bacteria pages are to be revised. You will continue to be able to search for the old names on phyla. The old phylum name Proteobacteria poses a particular problem because these bacteria were earlier divided into the classes Alpha-, Beta-, Gamma-, Delta- and Epsilonproteobacteria and, therefore, the class names should be changed too. One classes has been elevated to phylum status (Epsilonproteobacteria) and is now referred to as Campylobacterota.

Below is a list of the phyla whose names have been changed so far on VetBact. The old names are in brackets:

  • 2023-03-01: (Actinobacteria) ---> Actinomycetota
  • 2023-03-08: (Firmicutes) ---> Bacillota
  • 2023-03-08: (Spirochaetes) ---> Spirochaetota
  • 2023-03-15: (Chlamydiae)  --->  Chlamydiota
  • 2023-03-15: (Bacteroidetes)  --->  Bacteroidota
  • 2023-03-15: (Fusobacteria)  --->  Fusobacteriota
  • 2023-03-15: (Tenericutes)  --->  Mycoplasmatota
  • 2023-03-22: (Class Epsilonproteobacteria within the phylum Proteobacteria) ---> Campylobacterota
  • 2023-03-22: (Class Alphaproteobacteria within the phylum Proteobacteria) ---> Pseudomonadota
  • 2023-03-22: (Class Betaproteobacteria within the phylum Proteobacteria) ---> Pseudomonadota
  • 2023-03-22: (Class Deltaproteobacteria within the phylum Proteobacteria) ---> Thermodesulfobacteriota
  • 2023-03-29: (Proteobacteria)  --->  Pseudomonadota

The classes Alpha-, Beta- and Gammaproteobacteria still have their old names, even though it is illogical, since there are no Proteobacteria anymore. The classes Delta- and Epsilonproteobacteria are now called Desulfovibronia and Campylobacteria. The name of the phylum Cyanobacteria has not been changed, because these organisms have traditionally been sorted under the International Code of Botanical Nomenclature. VetBact is now completely up-to-date with regard to the phylum name and phylum affiliation of bacteria, however this does not rule out that new changes may occur in the future.

Published: 2023-03-01, updated: 2023-03-29.


New names of bacterial phyla

The taxonomic category phylum was previously not regulated by the International Code of Nomenclature of Prokaryotes (ICNP), but now this has changed and it was decided to revise the names of bacterial phyla. All phyla must be written in italics (which has been done on VetBact also before) and have the ending -ota.

Published 2023-03-01. Read more...
The taxonomy of chlamydias

Species within the family Chlamydiaceae were previously divided into two genera Chlamydia and Chlamydophila. However, the differences between these two genera were not that great and many research groups have not accepted this division. Therefore, the genus Chlamydophila has been returned to the genus Chlamydia and this change has now been incorporated in VetBact

Published 2023-03-15. Read more...

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