Iowa biologists unspool wild world of parasitic wasps

The hidden diversity of parasitic wasps

Parasitic wasps are one file card in Hymenoptera, the taxonomic order that includes ants, bees, and wasps. In that assemblage of insects, there are 150,000 described species, second only to Coleoptera, the order comprising beetles, which has 350,000 known species.

But that gap is narrowing, and discoveries of new parasitic wasp species is a big reason why. In the past few decades, scientists have found and detailed a dizzying array of parasitic wasps, many of them with fantastical tales of how they procreate, survive, and thrive.

There's the crypt-keeper wasp, so named because it entombs another wasp and then eats it whole as it gnaws its way out to freedom. There are other parasitic wasps that seduce, or manipulate, insects, from caterpillars to spiders, into bizarre, trancelike states that seal their demise but allow the wasps to feed and live on. And, in these parasite-host transactions, there can be additional layers of parasitism - parasitic wasps that are preying on the original parasitic wasp, using it as a host to deliver its progeny.

Start to add it all up, and Forbes' group is convinced there are a lot more species awaiting their moment of discovery.

"There are probably many hundreds more in the collections we have that need to be described, and we just haven't had a taxonomist here to do that," Forbes says.