Insect Identification
Insect Identification

Ichneumon Wasp - (Megarhyssa spp)

Authored By Staff Writer | Last Updated: 8/21/2015

The intimidating female Ichneumon Wasp has a tremendously long ovipositor for egg-laying, not for stinging.

There are several different species of Ichneumon Wasp, each with its own color variations. Some are black and yellow, others reddish and striped. All have the Ichneumon Wasp body shape: a thin waist and an abdomen longer than the rest of the body. Members of the family Ophion have abdomens that are shorter than Megarhyssa, but they are still long in comparison to more familiar wasps.

Females may have a long, needle-like ovipositor which is often mistaken as a stinger. The sturdy ovipositor acts like a syringe, injecting eggs deep into wood (live trees, or logs) where the larvae will feed on any other insect larvae already deposited there. It is not uncommon to see females poking around wood in an attempt to find a good place to deposit her eggs. Males do not have the ovipositor so their abdomen ('tails') are shorter. Both genders are still wasps, however, and capable of stinging if threatened.

See a female in motion here:

Giant Ichneumons tend to live in wooded areas and throughout all of North America, though they do stay away from the arid and hot desert regions and featureless plain states.

Ichneumon adults do not eat at all. Larvae are parasites of Pigeon Horntail larvae, another type of wasp that deposits eggs in wood. The Ichneumon larvae will hatch and feed on the Horntail Wasp larvae.

Variations of the Ichneumon include the Eastern Giant Ichneumon, the Lunar Giant Ichneumon and the Western Giant Ichneumon. These can all be found in their respective habitats consisting of Canada, the United States of America and Mexico. This is truly a North American insect!

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Category: Bee, Ant, Wasp and Similar
Common name: Ichneumon Wasp
Scientific Name: Megarhyssa spp

  Kingdom: Animalia
   Phylum: Arthropoda
    Class: Insecta
     Order: Hymenoptera
      Family: Ichneumonidae
       Genus: Megarhyssa
        Species: spp

Adult Size (Length): 10mm to 19mm (0.39in to 0.75in)

Identifying Colors: brown; yellow; black; orange; red, white

Additional Descriptors: long, tail, stinger, stinging

North American Reach (Though Not Limited To*): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Sasketchewan; Mexico

* Keep in mind that insect reach is not governed by lines on a map and therefore may appear in areas/regions/states beyond those listed above.