Archive for August 5th, 2009

Science at home: the Pelecinid wasp

by Katie Bowell, Curator of Cultural Interpretation

This afternoon I spotted a type of wasp in the museum’s courtyard that I’d never seen before. I grabbed my camera and took some pictures, knowing that I could compare the images to insect books and websites to help me in my identification. After some careful research I think that what I saw was … drum roll please … a pelecinid wasp!

“Why the excitement?,” you might ask. Well, let me tell you, these are some pretty nifty wasps. For example:

Worldwide, there’s only one extant (living) genus, Pelecinus, and three species, only one (Pelecinus polyturator) of which lives in North America.

The earliest fossil record of Pelecinid wasps was just found in Easter Inner Mongolia, China, dating to the Middle Jurassic (176-161 million years ago!).

Pelecinids are parasitoids. Parasitoids are organisms that spend a significant part of their life attached to or within a host organism that they eventually kill and usually consume. In the case of Pelecinid wasps, the female takes her ovipositor (the last segment of her abdomen, which she uses to lay eggs) and sticks it into the soil looking for beetle larvae. When she finds a larva, she lays an egg on it. The Pelecinid larva that hatches out of the egg will use the beetle larvae as its host and food source, ultimately killing the beetle.

In North America, male Pelecinid wasps are rare. As a result, most females reproduce by parthenogensis. Parthenogensis is basically a natural cloning process in which a female can lay unfertilized eggs that will hatch into replicas of the mother.

Where there’s one insect there’s always another, so keep your eyes out – you might just spot a Pelecinid wasp. Here’s how to identify it if you do:

August 2009

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 48 other followers

Flickr Photos