Spider-Devouring Wasp Discovered By USU Researchers

Dec 13, 2013

Two new species of wasps have been discovered by a pair of researchers from Utah State University. Professor James Pitts and graduate student Cecilia Waichert found the new species of spider wasps while examining a century-old Brazilian museum collection.

Two new species of spider wasps were discovered by USU researchers in Brazil.
Two new species of spider wasps were discovered by USU researchers in Brazil.
Credit Waichert and Pitts

Named for their method of reproduction, spider wasps lay a single egg on a spider they capture and paralyze. When the egg hatches, the young wasp feeds on the immobile spider.

“We had known these wasps occur in South America, but they had only been known from two species,” said Pitts. “One of them, the specimen was described before 1900, the other one was described around 1950 and both of these things are lost.”

Pitts said nearly 200,000 species in the wasp family—which includes ants—have been described. Scientists suspect there may be over 800,000 species yet to be described by science—making the discovery interesting, but not out of the ordinary.

Spider wasps are commonly found in Africa, but Pitts believes the South American species evolved separately.

“They look like each other because they are preying on the same host, but they are actually unrelated. We have molecular data showing that even though they look very similar, they come out in very different parts of the spider wasp family tree,” Pitts said.

The wasps have been named Abernessia giga and Abernessia capixaba. The team published their findings in the November issue of ZooKeys.