ICTV Report

Family: Malacoherpesviridae (Interim Report)

This is a summary page created by the ICTV Report Editors using information from associated Taxonomic Proposals and the Master Species List.

Edited by: Arvind Varsani, Paola K. Vaz and Thomas B. Waltzek
Posted: November 2024

Summary

The family Malacoherpesviridae includes dsDNA viruses of invertebrates (Table 1 Malacoherpesviridae). The family Malacoherpesviridae was established in 2008 (Master Species List #24).

Table 1 Malacoherpesviridae. Characteristics of members of the family Malacoherpesviridae.

CharacteristicDescription
Exampleoyster herpesvirus; ostreid herpesvirus 1 (AY509253), species Ostreavirus ostreidmalaco1, genus Ostreavirus
VirionEnveloped, mostly spherical virions of 100–180 nm diameter with an icosahedral capsid (Figure 1 Malacoherpesviridae)
GenomedsDNA of 207.4–211.6 kbp (Figure 2 Malacoherpesviridae)
ReplicationNuclear, lytic and latent infections: the pattern of gene expression is not yet established
TranslationmRNAs generally encode single proteins and are not spliced
Host rangeInvertebrates (molluscs)
TaxonomyRealm Duplodnaviria, kingdom Heunggongvirae, phylum Peploviricota, class Herviviricetes, order Herpesvirales: 2 genera, 2 species (Figure 3 Malacoherpesviridae)
Malacoherpesviridae
Figure 1 Malacoherpesviridae. (Left) Transmission electron micrograph of herpesvirus particles in tissues from an ostreid herpesvirus type 1-infected oyster. Negative-staining, 36Kx magnification (bar 500 nm). Image, Supplementary Figure 1 from Abbadi M, Zamperin G, Gastaldelli M, Pascoli F, Rosani U, et al. Identification of a newly described OsHV-1 μvar from the North Adriatic Sea (Italy). J Gen Virol. 2018 9):693-703. (Right) Schematic of virion. Image from ViralZone, under a Creative Commons Attribution 4.0 International License, credit: SwissBioPics.
Malacoherpesviridae genome
Figure 2 Malacoherpesviridae. Genome organisation of oyster herpesvirus, a member of the family Malacoherpesviridae. Boxes indicate open reading frames as annotated on GenBank accession AY509253.
Malacoherpesviridae taxonomy
Figure 3 Malacoherpesviridae. Taxonomy of the family Malacoherpesviridae. Labels in the column to the right are species names.

Derivation of names

Aurivirus: from the Latin for “ear” (auris) and secondarily from the Latin word for “gold” (aurum), to reflect a common name for abalones (ear-shell) and the shiny, iridescent layer of nacre on the inside of the shell

Malacoherpesviridae: from the Ancient Greek μαλακός (malakós), meaning ‘soft’ and used in zoology to denote molluscs, and the Ancient Greek: ἕρπης (hérpō), which is related to the meaning "to creep", referring to spreading blisters; the suffix -viridae for family taxa

Ostreavirus: from the Latin “ostrea”, meaning ‘oyster’