It’s estimated that there are 60,000 to 100,000 species of Ichneumon wasps worldwide, with approximately 5,000 to 8,000 inhabiting North America. They make up what may be the largest family of animals on the planet, and as a result they’re abundant in many areas. One of the more common North American species (Hymenoptera: Ichneumonidae: Vulgichneumon brevicinctor) can be seen here, resting on a fern in a forested area of northwest Ohio. These wasps can be found across most of the United States and southern Canada.
Ichneumon wasps are endoparasitic. Adult females use their sharp, slender ovipositors to insert eggs into living host insects. Their eggs hatch and devour the hosts from the inside, eventually killing them before emerging. Many of these wasps prey upon hosts that also happen to be crop pests, and likely provide an invaluable service to agriculture. The species shown here, in particular, is known to attack cabbage looper moths (Lepidoptera: Noctuidae: Trichoplusia ni), European corn borers (Lepidoptera: Crambidae: Ostrinia nubilalis), and fall webworm moths (Lepidoptera: Erebidae: Hyphantria cunea).