Parasitic Wasp Identification: How To Find Parasitic Wasp Larvae And Eggs

Image by Daiju Azuma

By Mary H. Dyer, Master Naturalist and Master Gardener

If you’re like most people, the idea of any type of wasp can set your nerves on edge. However, not all wasps are the scary, stinging type. In fact, we should all encourage the presence of parasitic wasps in gardens. Parasitic wasps, which aren’t the least bit interested in bothering humans, spend much of their lives working hard, either within or outside the body of a host insect.

Parasitic wasps parasitize different garden pests depending on species. These garden good guys can help control:

Read on to learn more about these beneficial insects.

Parasitic Wasp Identification


Parasitic wasps belong to the family Hymenoptera, which includes friendly honeybees and those angry, stinging wasps. Size of parasitic wasps varies greatly. Larger species can be nearly an inch in length, while species that develop within the egg of a host insect tend to be miniscule.

When it comes to parasitic wasp identification, things get complicated. However, like other wasps, parasitic wasps have the appearance of a “waist,” which is actually the constriction between the insect’s abdomen and thorax. Most adults have two sets of wings, although some may be wingless in the adult stage.

Their antennae may vary as well and can be either short or long. Color? Again, there is no single answer, as parasitic wasps may be brown, black, or metallic green or blue. Some are marked with bright orange or yellow stripes.

Life Cycle of Parasitic Wasps

There are many types of parasitic wasps in gardens and some have extremely complex and interesting life cycles. For example, some species are able to reproduce without help of male wasps, which apparently don’t even exist; the female is able to do it all by herself without mating.

Some species produce several generations of offspring in a single season, while others take more than a year to develop a single adult.

So, the life cycle of parasitic wasps is something you may want to research on your own, as the topic is beyond the scope of this article. However, we can say that, in general, parasitic wasps advance through a complete life cycle – egg, larvae, pupae and adult.

Parasitic Wasp Eggs

All female parasitic wasps possess an organ called an ovipositor, located at the tip of the abdomen. This long structure allows the wasps to deposit parasitic wasp eggs inside host insects, even when the hosts are hidden within tree bark or cocoons.

Most eggs contain a single larva, but some species produce multiple parasitic wasp larvae within a single egg.

Parasitic Wasp Larvae

Parasitic wasp larvae are garden heroes. Some species spend their entire development within the body of the host insect, while others may be embedded on the exterior of the host (which may be in various stages of development from egg to adult). Some parasitic wasps may start out on the exterior of the host, gradually working their way into the body.

The host pests may become inactive very quickly, or may continue to live normally for a short while with the parasitic wasp larva growing inside its body. Once the larva is nearly mature, however, the host is a goner for sure. The larva may exit the host before pupating or it may pupate inside the body of the deceased host.

Print This Article
This article was last updated on
Did you find this helpful?
Share it with your friends!

Additional Help & Information

Didn't find the answer to your question? Ask one of our friendly gardening experts.

Do you know anything about gardening? Help answer someone's gardening question.

Read more articles about Beneficial Garden Friends.

Search for more information

Use the search box below to find more gardening information on Gardening Know How: