Family: Bornaviridae

Genus: Cultervirus

Distinguishing features

Culterviruses are currently known only from a fish through metagenomic sequencing (Shi et al., 2018, Costa et al., 2021).

Virion

Morphology

Not reported.

Physicochemical and physical properties

Not reported.

Nucleic acid

The Wǔhàn sharpbelly bornavirus (WhSBV) genome consists of negative-sense non-segmented single-stranded RNA (about 8.99 kb).

Proteins

Based on sequence comparisons, cultervirus genomes encode homologs of orthobornavirus proteins N, X, P, M, G, and L (see Table 1.Orthobornavirus in the Orthobornavirus genus section).

Lipids

Not reported.

Carbohydrates

Not reported.

Genome organization and replication

The cultervirus genome organization resembles that of carboviruses by having the gene order 3′-N-X/P-G-M-L-5′ (Shi et al., 2018). The replication of culterviruses has not yet been described.

Biology

The presumed reservoir hosts of culterviruses are fish. WhSBV was sequenced from a specimen of a sharpbelly (Actinopterygii: Cyprinidae: Hemiculter leucisculus (Basilewsky, 1855)) in Wǔhàn, Húběi Province, China (Shi et al., 2018), whereas the sequence of Murray-Darling carp bornavirus (MDCBV) originates from a common carp (Actinopterygii: Cyprinidae: Cyprinus carpio [Linnaeus, 1758]) from the Murray-Darling basin, Australia (Costa et al., 2021).

Species demarcation criteria

The genus only includes a single species.