Ichneumon Wasps

Depending on the source, possibly ten thousand different Ichneumon species inhabit North America, making identification of any one species difficult.

Ichneumon wasps (Ichneumonidae) sharing some physical and behavioral traits.

Physically, many are long, thin-waisted wasps, often having a red and black or yellow and black color combination on the thorax and abdomen.

Unlike other wasp species, the abdomen tends to be on the long and thin side, and the antennae is longer, often containing at least sixteen segments.

Females are further differentiated by the presence of an extended ovipositor (not show in the picture), whose utility is derived from the wasp's parasitic reproductive strategy.

Like many wasp families, Ichneumon attack potential insect hosts such as caterpillars, and paralyse them prior to depositing their eggs. When the young are born they feed on the host.

While they may look menacing, most ichneumon wasps are not known to sting, and males have no stinger.

Braconid Wasps (Family Braconidae), the other large Ichneumonoidea wasp family generally get identified by size.

Most of the 1,700 different North American species measure between 1/8 to 5/8 inches long.

Like Ichneumon wasps, their thin bodies come accompanied by long antennae. In females a long oviposter can also be seen.

A close up view of Braconid wings also helps distinguish them from Ichneumon wasps. Usually Broconid wings have less venation, or less veins, and a smaller number of segments, than the Ichneumon wasps.

Organic gardeners as well as larger scale farmers rely on braconid species to provide natural biological controls against pests such as aphids, cabbage and tomato worms in check.

Brightly colored Ichneumon species ranks among the more easily identified.

The dusty, darkly marked wings and bright orange body of the Compsocryptus species in the picture make it stand out against its green grass background.

They are primarily a southern species.

The picture crops the antennae. However, some other pictures show both the presence and absence of white bands on the antennae.

The existence of so many red abdomen Ichneumon wasps makes finding a brown and yellow species fun.

Grotea californica is one of two identified Grotea species and it can be found flying in California and Oregon.

The picture shows a specimen enlarged by a factor of two.

The Xoridinae group of ichneumon wasps consists of four native genera, often considered rare.

Physically they are described as medium sized, about two inches in length, with females having long ovipositors.

A close up picture shows an epomia with what looks to be a tooth-like projection.

They inhabit older groth forests and use beetles as their larval hosts.

Like other parasitoids of wood-boring insects female, xoridines possess a long conspicuous ovipositor.

Species in the Xorides genus can be found through most of the United States in areas with older growth forests.

In southern areas, Xorides species are usually the only Xoridinae representatives.

© 2006-2011 Patricia A. Michaels.