Courtesy of UC Riverside Newsroom

“Gonatocerus ater,” a wasp native to Europe, was recently found in Southern California by UC Riverside Entomologist Serguei Triapitsyn. This discovery prompted Triapitsyn to form a theory regarding the intercontinental movement of the wasp. “It is of European origin but likely has been present in North America for a long time,” said Triapitsyn in an email correspondence with the Highlander. In 2010, Triapitsyn first discovered the wasp on U.S. soil in upstate New York. The Southern California discovery occurred in Irvine.

“Gonatocerus ater” poses a great threat to leafhopper insects. Female “gonatocerus ater” lay their eggs inside of leafhoppers, eventually killing the insect. Due to the recent nature of the discovery, however, scientists have not yet determined which specific type of leafhopper is targeted by Southern California’s variant of the wasp.

“This species belongs to the large genus Gonatocerus of the wasp family Mymaridae, in the insect order Hymenoptera. Almost all mymarids, or fairyflies, are parasitoids of eggs of other insects. Some other species (but not this one) in the genus have been used in biological control programs against agricultural pests, such as the glassy-winged sharpshooter,” Triapitsyn said.

Triapitsyn noted that his search for the wasp in the Irvine area had started out of curiosity. “I was curious if one, two, or none of the Gonatocerus species I had found earlier on Lombardy poplars (which are non-native trees in North America) in NY would show up in [Irvine], so on one weekend day I took my net and swept over the poplars,” said Triapitisyn. “Then, in my lab back at UCR I recognized one female but it took a while to prepare and identify it properly…I compared it with specimens from NY and also the type specimens borrowed from the European museums (from Austria and Italy) to be sure,” said Triapitsyn.

“Gonatocerus ater” wasps are generally harmless to humans and are used as a natural defense to control the population of leafhoppers. The wasps can also be used as an alternative to chemical pesticides that could harm the environment.