Family: Deltaflexiviridae (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: Sead Sabanadzovic
Posted: February 2025
Summary
The family Deltaflexiviridae includes RNA(+) viruses of fungi (Table 1 Deltaflexiviridae). The genome of about 6–8 kb and encodes an RNA-dependent RNA polymerase (RdPR)The family Deltaflexiviridae was established in 2018 (Master Species List #32).
Table 1 Deltaflexiviridae. Characteristics of members of the family Deltaflexiviridae.
| Characteristic | Description |
| Example | Sclerotinia sclerotiorum deltaflexivirus 1 (KT581451), species Deltaflexivirus sclerotiniae, genus Deltaflexivirus |
| Virion | Not known |
| Genome | RNA(+), 6-8 kb, capped, polyadenylated (Figure 1 Deltaflexiviridae) |
| Replication | Involves dsRNA |
| Translation | Possible subgenome sized mRNA |
| Host range | Fungi |
| Taxonomy | Realm Riboviria, kingdom Orthornavirae, phylum Kitrinoviricota, class Alsuviricetes, order Tymovirales: one genus and four species (Figure 2 Deltaflexiviridae) |
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| Figure 1 Deltaflexiviridae. Genome organisation of Sclerotinia sclerotiorum deltaflexivirus 1, a member of the family Deltaflexiviridae. Boxes indicate open reading frames as annotated on GenBank accession KT581451. |
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| Figure 2 Deltaflexiviridae. Taxonomy of the family Deltaflexiviridae. |
Derivation of names
Deltaflexiviridae, Deltaflexivirus: from the Ancient Greek δέλτα (délta), the number 4, and flexi, together referring to the fourth family created from the division of the old family Flexiviridae, a group of filamentous and highly flexible viruses; the suffix -viridae for family taxa and -virus for genus taxa



