# Ichnovirus

Ichnovirus is a genus of viruses, in the family Polydnaviridae. Parasitoid wasps serve as hosts, and these wasps are themselves parasitoids of Lepidoptera. There are 21 species in this genus.

## Taxonomy

The genus Ichnovirus contained 21 species in ICTV version 1999a-2020: The genus Ichnoviriform contains 22 species starting ICTV version 2021 The species Ichnoviriform rostralis, previously known as Tranosema rostrale bracovirus was moved to ichnoviriform from bracoviriform (bracovirus) in 2021.
| Species | Previous name, Virus name | Abbreviation |
| Ichnoviriform acronyctae | Diadegma acronyctae ichnovirus | DaIV |
| Ichnoviriform annulipedis | Hyposoter annulipes ichnovirus | HaIV |
| Ichnoviriform aprilis | Campoletis aprilis ichnovirus | CaIV |
| Ichnoviriform arjunae | Casinaria arjuna ichnovirus | CarIV |
| Ichnoviriform benefactoris | Olesicampe benefactor ichnovirus | ObIV |
| Ichnoviriform eribori | Eriborus terebrans ichnovirus | EtIV |
| Ichnoviriform exiguae | Hyposoter exiguae ichnovirus | HeIV |
| Ichnoviriform flavicinctae | Campoletis flavicincta ichnovirus | CfIV |
| Ichnoviriform forcipatae | Casinaria forcipata ichnovirus | CfoIV |
| Ichnoviriform fugitivi | Hyposoter fugitivus ichnovirus | HfIV |
| Ichnoviriform fumiferanae | Glypta fumiferanae ichnovirus | GfIV |
| Ichnoviriform geniculatae | Olesicampe geniculatae ichnovirus | OgIV |
| Ichnoviriform infestae | Casinaria infesta ichnovirus | CiIV |
| Ichnoviriform interrupti | Diadegma interruptum ichnovirus | DiIV |
| Ichnoviriform lymantriae | Hyposoter lymantriae ichnovirus | HlIV |
| Ichnoviriform montani | Enytus montanus ichnovirus | X-2 |
| Ichnoviriform pilosuli | Hyposoter pilosulus ichnovirus | HpIV |
| Ichnoviriform rivalis | Hyposoter rivalis ichnovirus | HrIV |
| Ichnoviriform rostralis | Tranosema rostrale bracovirus | TrBV |
| Ichnoviriform sonorense | Campoletis sonorensis ichnovirus | CsIV |
| Ichnoviriform tenuifemoris | Synetaeris tenuifemur ichnovirus | StIV |
| Ichnoviriform terebrantis | Diadegma terebrans ichnovirus | DtIV |

## Structure

Viruses in Ichnovirus are enveloped, with prolate ellipsoid and cylindrical geometries. Genomes are circular and segmented, around 6.0-20kb in length.
| Genus | Structure | Symmetry | Capsid | Genomic arrangement | Genomic segmentation |
| Ichnovirus | Prolate ellipsoid | | Enveloped | Circular | Segmented |

## Life cycle

Viral replication is nuclear. DNA-templated transcription is the method of transcription. The virus exits the host cell by nuclear pore export. Parasitoid wasps in the subfamilies Banchinae and Campopleginae serve as hosts, but these wasps are themselves parasites of lepidoptera. The wasp injects one or more eggs into its host along with a quantity of virus. The virus and wasp are in a symbiotic relationship: expression of viral genes prevents the wasp's host's immune system from killing the wasp's injected egg and causes other physiological alterations that ultimately cause the parasitized host to die. Transmission routes are parental.
| Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
| Ichnovirus | Parasitoid wasps (Ichneumonidae) | Hemocytes; fat bodies | Unknown | Lysis; budding | Nucleus | Nucleus | Unknown |