Virus classification is the process of naming viruses and placing them into a taxonomic system similar to the classification systems used for cellular organisms.
Parvoviruses are a family of animal viruses that constitute the family Parvoviridae. They have linear, single-stranded DNA (ssDNA) genomes that typically contain two genes encoding for a replication initiator protein, called NS1, and the protein the viral capsid is made of. The coding portion of the genome is flanked by telomeres at each end that form into hairpin loops that are important during replication. Parvovirus virions are small compared to most viruses, at 23–28 nanometers in diameter, and contain the genome enclosed in an icosahedral capsid that has a rugged surface.
Myoviridae was a family of bacteriophages in the order Caudovirales. The family Myoviridae and order Caudovirales have now been abolished, with the term myovirus now used to refer to the morphology of viruses in this former family. Bacteria and archaea serve as natural hosts. There were 625 species in this family, assigned to eight subfamilies and 217 genera.
Podoviridae was a family of bacteriophage in the order Caudovirales often associated with T-7 like phages. The family and order Caudoviraleshave now been abolished, with the term podovirus now used to refer to the morphology of viruses in this former family. There were 130 species in this family, assigned to 3 subfamilies and 52 genera. This family was characterized by having very short, noncontractile tails. Many former phages in the former family Podoviriade are now classified in the Autographiviridae
Caudoviricetes is a class of viruses known as the tailed bacteriophages. Under the Baltimore classification scheme, the Caudoviricetes are group I viruses as they have double stranded DNA (dsDNA) genomes, which can be anywhere from 18,000 base pairs to 500,000 base pairs in length. The virus particles have a distinct shape; each virion has an icosahedral head that contains the viral genome, and is attached to a flexible tail by a connector protein. The order encompasses a wide range of viruses, many containing genes of similar nucleotide sequence and function. However, some tailed bacteriophage genomes can vary quite significantly in nucleotide sequence, even among the same genus. Due to their characteristic structure and possession of potentially homologous genes, it is believed these bacteriophages possess a common origin.
The International Committee on Taxonomy of Viruses (ICTV) authorizes and organizes the taxonomic classification of and the nomenclature for viruses. The ICTV develops a universal taxonomic scheme for viruses, and thus has the means to appropriately describe, name, and classify every virus taxon. The members of the International Committee on Taxonomy of Viruses are considered expert virologists. The ICTV was formed from and is governed by the Virology Division of the International Union of Microbiological Societies. Detailed work, such as identifying new taxa and delimiting the boundaries of species, genera, families, etc. typically is performed by study groups of experts in the families.
The Herpesvirales is an order of dsDNA viruses with animal hosts, characterised by a common morphology consisting of an icosahedral capsid enclosed in a glycoprotein-containing lipid envelope. Common infections in humans caused by members of this order include cold sores, genital herpes, chickenpox, shingles, and glandular fever. Herpesvirales is the sole order in the class Herviviricetes, which is the sole class in the phylum Peploviricota.
Globuloviridae is a family of hyperthermophilic archaeal viruses. Crenarchaea of the genera Pyrobaculum and Thermoproteus serve as natural hosts. There are four species in this family, assigned to a single genus, Alphaglobulovirus.
Autographiviridae is a family of viruses in the order Caudovirales. Bacteria serve as natural hosts. There are 373 species in this family, assigned to 9 subfamilies and 133 genera.
Okubovirus is a genus of viruses in the order Caudovirales, in the family Herelleviridae, in the subfamily Spounavirinae. Bacteria serve as natural hosts. There are two species in this genus.
Escherichia virus Wphi is a virus of the family Myoviridae, genus Peduovirus.
Pseudomonas virus phiCTX is a virus of the family Myoviridae, genus Citexvirus.
Ralstonia virus RSA1 is a virus of the family Myoviridae, genus Aresaunavirus.
Proboscivirus is a genus of viruses in the order Herpesvirales, in the family Herpesviridae, in the subfamily Betaherpesvirinae. Elephants serve as natural hosts. EEHV1 is apathogenic for African elephants but causes fatal haemorrhagic disease in Asian elephants. The name "Proboscivirus" comes from the Greek word προβοσκίς or "proboscis" meaning "the elephant trunk," for which the virus accordingly uses as its means of contraction and transmission to enter the elephant's body.
Peduovirus is a genus of viruses in the family Peduoviridae the class Caudoviricetes. Bacteria serve as natural hosts, with transmission achieved through passive diffusion. There are 30 recognised species in this genus.
Tequatrovirus is a genus of viruses in subfamily Tevenvirinae of family Straboviridae. Gram-negative bacteria serve as the natural host, with transmission achieved through passive diffusion. There are 84 species in this genus.
Peduoviridae is a family of viruses in the class Caudoviricetes. It was previously treated as a subfamily of the morphology based family Myoviridae, which has been found to be paraphyletic and is no longer recognised. Bacteria serve as natural hosts. There are 126 species in this subfamily, assigned to 58 genera.
Tevenvirinae is a subfamily of viruses in the family Straboviridae of class Caudoviricetes. The subfamily was previously placed in the morphology-based family Myoviridae, which was found to be paraphyletic in genome studies and abolished in the 2021 International Committee on Taxonomy of Viruses (ICTV) classification. Bacteria and archaea serve as natural hosts. There are 148 species in this subfamily, included in 14 genera.
Eucampyvirinae is a subfamily of viruses in the order Caudovirales, in the family Myoviridae. Bacteria of the genus Campylobacter serve as natural hosts. There are 9 species in this subfamily, assigned to 2 genera.
Kyanoviridae is a family of bacteriophages in the class Caudoviricetes. The viruses in this family were formerly place in the morphology-based family Myoviridae, which was found to be paraphyletic in genome studies and abolished in the 2021 International Committee on Taxonomy of Viruses (ICTV) classification, although the term myovirus is still used to refer to the morphology of viruses in this new family. Bacteria and archaea serve as natural hosts. There are currently 66 species in this family, assigned to 54 genera.
