Tiny European wasp makes U.S. home

RIVERSIDE, Calif., Jan. 24 (UPI) -- A tiny wasp found in upstate New York in 2010 that had never been seen before in the United States has turned up in California, researchers say.

A University of California, Riverside, entomologist who made both discoveries says it strongly suggests the fairyfly wasp, originally from Europe, is well established in the United States.

Called Gonatocerus ater, the wasp lays its eggs inside the eggs of leafhoppers, and the wasp larvae that hatch consume the leafhopper eggs.

"This wasp was accidentally introduced in North America," Serguei Triapitsyn, director of the university's Entomology Research Museum, said in university release Tuesday. "It most likely got here in parasitized eggs of the leafhoppers in twigs of Lombardy poplar seedlings coming from Europe, perhaps long ago."

"I identified the wasp as Gonatocerus ater by comparing it to wasps from upstate New York and also Europe," he said. "It would not surprise me if this wasp is found wherever Lombardy poplars are located because its likely leafhopper host prefers these trees for feeding."

The wasp poses no known ecological risk, he said, other than killing leafhopper eggs.

"It actually helps naturally control leafhopper numbers," he said. "In its absence, leafhopper populations could have skyrocketed. This illustrates how plant pests are sometimes accompanied by their natural enemies across very long distances without our knowledge."