The whirligig mite Anystis: An underappreciated source of psyllid biocontrol

In Washington State, potato psyllid (Bactericera cockerelli; Psylloidea) utilizes several weedy Solanaceae as alternate hosts. Consequently, psyllid pressure in commercial potato fields can be governed a great deal by processes occurring outside of the crop field. One such process is biological control. The predatory taxa most important in providing biological control of potato psyllid in these habitats are poorly known. Predators were sampled from weeds and tested using targeted PCR to identify species harboring the DNA of potato psyllids. Predatory mites in the genus Anystis were found to be present throughout the region on multiple plant species and tested positive for potato psyllid DNA in 15.8% of specimens. Lab assays showed that Anystis readily consumed potato psyllid nymphs. Gut content analysis using barcoded universal primers showed that Anystis sp. is a broadly generalized predator and readily preys on several arthropod pests, including leafhoppers, thrips, herbivorous mites, aphids, Lygus sp., caterpillars, and potato psyllids. Our results suggest that Anystis sp. has potential as a biocontrol agent for managing potato psyllids and other pests, including in non-crop habitats.