RNA virus discoveries in the electric ant, Wasmannia auropunctata

Authors: Valles, Steven; Zhao, Chaoyang; Rivers, Adam; IWATA, RYO - Former ARS Employee; Oi, David; Cha, Dong; COLLIGNON, R. MAX - Department Of Agriculture And Fisheries; COX, NASTASSJA - Department Of Agriculture And Fisheries; MORTON, GARY - Department Of Agriculture And Fisheries; CALCATERRA, LUIS - Fuedei

Submitted to: Virus Genes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/13/2023
Publication Date: 2/2/2023
Citation: Valles, S.M., Zhao, C., Rivers, A.R., Iwata, R.L., Oi, D.H., Cha, D.H., Collignon, R., Cox, N.A., Morton, G.J., Calcaterra, L.A. 2023. RNA virus discoveries in the electric ant, Wasmannia auropunctata. Virus Genes. 59:276–289. https://doi.org/10.1007/s11262-023-01969-1.
DOI: https://doi.org/10.1007/s11262-023-01969-1

Interpretive Summary: Wasmannia auropunctata, commonly known as the electric ant or little fire ant, is one of the most destructive invasive species of ants worldwide. Currently, only two natural enemies are known for this ant. Because viruses can be effective natural control agents against many insect pests, including ants, a metagenomics approach was used by scientists at the USDA (Gainesville, Florida and Hilo, Hawaii), Biosecurity Queensland (Queensland, Australia), and Fundación para el Estudio de Especies Invasivas (Hurlingham, Argentina) to facilitate discovery of viruses from the genes of the electric ant collected from areas within native and introduced ranges. Seven new viruses were discovered in electric ants from its native range, which offer potential candidates for classical biological control agents in introduced regions globally.

Technical Abstract: Despite being one of the most destructive invasive species of ants, only two natural enemies are known currently for Wasmannia auropunctata, which is commonly known as the electric ant or little fire ant. Because viruses can be effective biological control agents against many insect pests, including ants, a metagenomics/next generation sequencing approach was used to facilitate discovery of virus sequences (viruses by proxy) from the transcriptomes of W. auropunctata collected from areas within the native and introduced ranges. Six new and complete positive sense, single stranded RNA virus genomes and one negative sense, single stranded RNA virus genome were identified, sequenced, and characterized from transcriptomes of W. auropunctata collected in Argentina by this approach, including a dicistrovirus (Electric ant dicistrovirus), two polycipiviruses (Electric ant polycipivirus 1 and Electric ant polycipivirus 2), a solinvivirus (Electric ant solinvivirus), two divergent genomes with similarity to unclassified groups (Electric ant virus 1; Electric ant virus 2), and a rhabdovirus (Electric ant rhabdovirus). The virus genome sequences were absent from the transcriptomes of W. auropunctata collected in the USA (Hawaii and Florida). Additional field surveys corroborated the absence of these viruses in regions where the electric ant is invasive (USA and Australia). The replicative genome strand of four of the viruses (Electric ant polycipivirus 2, Electric ant solinvivirus, Electric ant virus 1, and Electric ant virus 2) was detected in W. auropunctata (Argentinean-collected) indicating that the ant is a host for these viruses. Sustainable control of W. auropunctata will rely on natural enemies. The virus sequences discovered and described here were limited to Argentinean W. auropunctata indicating that they offer at least the potential as candidates for classical biological control agents in introduced regions globally.