During a walk last fall at the Severson Dells Forest Preserve, Nature Center volunteer Francie Barnes found a giant wasp-like insect in the process of laying her eggs. Fortunately, she was close enough to her car to retrieve a video camera and captured the insect — probably a Megarhyssa macrurus, a non-stinging relative of wasps — through the lens.


This female is doing what a scientist would call ovipositing.

The long stingerlike “tail” is called an ovipositor. it is looped near the back of her abdomen and then it extends under her legs, then into the bark of the tree. The ovipositor is like a drill that allows the insect to drill into the wood.

She then uses the it to lay eggs deep int wood infested with bark beetles and other borers. When the eggs hatch, they will feed on the larva of these beetles.