Subfamily: Alpharhabdovirinae

Genus: Zarhavirus

 

Distinguishing features

Viruses assigned to the genus Zarhavirus form a distinct monophyletic group based on well-supported Maximum Likelihood or Maximum Clade Credibility trees inferred from complete L sequences. Zahedan rhabdovirus (ZARV; species Zarhavirus zahedan) was isolated from hard ticks.

Virion

Morphology

Virion morphology is unknown.

Nucleic acid

The ZARV genome consist of a single molecule of negative-sense, single-stranded RNA of approximately 13.2 kb (Dilcher et al., 2015).

Proteins

The ZARV N, P, M, G and L proteins share sequence homology and/or structural characteristics with the cognate proteins of other rhabdoviruses.

Genome organisation and replication

The ZARV genome includes only the five genes (N, P, M, G and L) encoding the structural protein (Figure 1.Zarhavirus).

Zarhavirus genome
Figure 1.Zarhavirus. Schematic representation of the Zahedan rhabdovirus genome shown in reverse (positive-sense) polarity. The genome contains only five long open reading frames (ORFs) in the N, P, M, G and L genes (open arrows).

Biology

ZARV was isolated from hard ticks (Hyalomma anatolicum anatolicum) collected in 2001, in Zahedan, Iran (Dilcher et al., 2015). The virus has been shown to replicate in Vero cell cultures and newborn mice (Dilcher et al., 2015).

Species demarcation criteria

There is only one species in the genus. For viruses to be assigned additional species in the genus, several of the following characteristics would have to be observed: A) minimum amino acid sequence divergence of 10% in the N proteins; B) minimum amino acid sequence divergence of 10% in the L proteins; C) minimum amino acid sequence divergence of 15% in the G proteins; D) significant differences in genome organisation as evidenced by numbers and locations of ORFs; E) they can be distinguished in virus neutralisation tests; and F) they occupy different ecological niches as evidenced by differences in vertebrate hosts and or arthropod vectors.