Family: Ungulaviridae (interim)

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

Edited by: Mart Krupovic
Posted: April 2023


The family Ungulaviridae includes dsDNA viruses infecting hyperthermophilic archaea of the genus Acidianus (Table 1.Ungulaviridae). The family was assigned to the realm Adnaviria in 2022 (Master Species List 37).

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




Acidianus filamentous virus 1 (AJ567472), species Captovirus AFV1, genus Captovirus


Filamentous, flexible enveloped particle consisting of a nucleoprotein core with heterodimeric major capsid proteins, terminal claw-like structures


Linear, double-stranded DNA genome of 20 kbp

Host range

Hyperthermophilic archaea of the genus Acidianus


Realm Adnaviria, kingdom Zilligvirae, phylum Taleaviricota, class Tokiviricetes, order Ligamenvirales: 1 genus and 1 species

Ungulaviridae genome

Figure 1.Ungulaviridae. Genome organisation of a member of the family Ungulaviridae. Boxes indicate open reading frames as annotated on GenBank accession AJ567472.

Ungulaviridae taxonomy

Figure 2.Ungulaviridae. Relationships of the taxa connected to the family Ungulaviridae.

Derivation of name

Ungulaviridae: from the Latin ungula, meaning "claw".