Argentine ants, Linepithema humile, are one of the world’s most widespread, abundant, and damaging invasive ants. But now, researchers have just discovered a novel virus carried by these global invaders that they think may offer new options for ant control. Unfortunately, the team also found that these invasive ants host another virus that threatens to devastate honeybees. The findings were published in Biology Letters this week.
A team led by Phil Lester from Victoria University of Wellington discovered the first virus – dubbed Linepithema humile virus 1 (LHUV-1) – after extracting RNA from Argentine ants collected from two nests in New Zealand back in 2013. LHUV-1 belongs to the Dicistroviridae family, which includes viral pathogens known to cause arthropod diseases. It has since been detected in samples from Australia and the ants’ native range of Argentina.
The survey of viruses also revealed that Argentine ants (in New Zealand at least) are a common host for Deformed Wing Virus (DWV), a pathogen implicated in honeybee mortality. And because the DWV strains found in the ants were similar to those from local bee and wasp populations, the researchers think that the ants, wasps, and bees are sharing pathogen strains. A direct transmission of the virus can occur when Argentine ants raid beehives.
Until now, no viruses have been described from Argentine ants or other invasive ants, with the exception of red imported fire ants (Solenopsis invicta), which are pests in multiple countries outside of South America. So far, six dicistroviruses have been described from red imported fire ants, and some are being considered as potential biocontrol agents. Both LHUV-1 and the DWV appear to be actively replicating in Argentine ants – which suggests that the viruses are parasitizing the ants, making them a good candidate for the control of these global invaders.