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Giant Ichneumon Wasp (Megarhyssa nortoni)

Detailing the identifying qualities of the Giant Ichneumon Wasp, including physical features and territorial reach.

 Updated: 8/15/2017; Authored By Staff Writer; Content ¬©

  Giant Ichneumon Wasp  
Picture of Giant-Ichneumon-Wasp-Megarhyssa-Nortoni
Picture of Giant-Ichneumon-Wasp-Megarhyssa-Nortoni Picture of Giant-Ichneumon-Wasp-Megarhyssa-Nortoni

The long, syringe-like ovipositor on female Ichneumon Wasps looks like a mean stinger, but it's really all about the babies.

The size of M. nortoni alone creates anxiety among people who don't know about this wasp. It has a long, slender abdomen, dotted with red and yellow ovals or hexagons on each segment. The mainly black body sports yellow legs. Females have long needle-like ovipositors that are mistaken for flexible stingers. This ovipositor doubles the length of the insect, but it is not a stinger. It is a thin tube that females inject into tree bark where they suspect Horntail larvae have been implanted. She lays a fertilized egg on or near a Horntail larva inside the bark where the Horntail will serve as food for her own offspring once it hatches. M. nortoni seems to specifically parasitize Horntails.

Look for this species of Ichneumon Wasp on trees in deciduous forests and parks.

Picture of the Giant Ichneumon Wasp
Picture of the Giant Ichneumon Wasp

Giant Ichneumon Wasp Information

Category: Bee, Ant, Wasp and Similar
Common Name: Giant Ichneumon Wasp
Scientific Name: Megarhyssa nortoni

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Hymenoptera
     Arrow graphic Family: Ichneumonidae
      Arrow graphic Genus: Megarhyssa
       Arrow graphic Species: nortoni

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 25 mm to 38 mm (0.975 inches to 1.482 inches)
Identifying Colors: black, yellow, red
Additional Descriptors: needle, sting, thread, poke, tree, wasp, flying, multicolored

North American Territorial 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; Saskatchewan; Mexico

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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