Our warm weather also started bringing out an assortment of insects including this Ichneumon Wasp that joined me in my basement shop. According to BugGuide, the Ichneumon Wasp family (Ichneumonidae) is one of the largest families of insects, with over 60,000 species worldwide and over 3100 in North America. A few of the Ichneumons are distinctive, but most are difficult to identify even to the genus level.
According to the University of Illinois site:
Ichneumons are parasitoid: The larva feeds and develops on or in a single host that it eventually kills. Some attack a wide variety of hosts, others are highly specific to one or a small group of host species. A female wasp locates an appropriate host, and she
lays an egg on or near it. After hatching, the larva feeds either from the outside of the host (external parasite) or within the body cavity (internal parasite).
The hosts are often caterpillars, but can be anything from aphids to spiders. The essay by Stephen Jay Gould listed below has a more detailed description of the larvae feeding process.
One characteristic shared by most Ichneumons are long, slender antennae made up of many (at least 16) small segments. If you click on the photo above and enlarge, you can see the numerous tiny segments in this Ichneumon's antennae.
Sources and additional material:
