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Species Megarhyssa atrata - Black Giant Ichneumonid Wasp

Unknown: Giant Ichneumon - Megarhyssa atrata - female Wasp Spp - Megarhyssa atrata - female Giant Ichneumon Wasp - Megarhyssa atrata - male Wasp1 - Megarhyssa atrata - male Megarhyssa atrata - male ichneumonid? - Megarhyssa atrata Ichnuemon - Megarhyssa atrata - female
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon ("Parasitica" - Parasitoid Wasps)
Superfamily Ichneumonoidea (Braconid and Ichneumonid Wasps)
Family Ichneumonidae (Ichneumonid Wasps)
Subfamily Rhyssinae
Genus Megarhyssa (Giant Ichneumonid Wasps)
Species atrata (Black Giant Ichneumonid Wasp)
Other Common Names
La Rhysse noirâtre
Synonyms and other taxonomic changes
Megarhyssa atrata (Fabricius, 1781)
=Megarhyssa atrata lineata Porter, 1957(1)(2)
=Megarhyssa atrata atrata (Fabricius, 1781)
Orig. Comb.: Ichneumon atratus Fabricius, 1781
Explanation of Names
Megarhyssa atrata (Fabricius, 1781)
atrata = from the Latin ātrāta ('clothed in black as for mourning')
Female: body is 38 mm, ovipositor 130 mm, antennae 24 mm.
Male: 35 mm (body), antennae 13 mm
Females of M. atrata are very distinctive with a dark black body and yellow head.(2) No other species is easily confused.

Males are fairly similar to other males of this genus. They may be identified by their clear wings, yellow-lined mesoscutum, and dark or black-and-yellow hind femora. They may, though not always, have a darker abdomen. (See Internet references.)
Eastern North America: widespread, reported from Quebec, Michigan, Ohio, Carolinas, Florida.
Forests, esp. deciduous forests.
May-July (North Carolina)
Adults may not feed.
Life Cycle
Parasitoids of wood-boring insects. From Florida, hosts are listed as: Siricid (woodwasp) larvae (including Tremex, Eriotremex?) in dead deciduous trees.
See Also
Other Megarhyssa
Print References
Brimley, p. 410 (3)
Internet References
North Carolina State University Entomology lists all four species for that state, with number pinned in collection: atrata (32), greeni (16), macrurus (79), nortoni (8).
Insects of Quebec page on M. atrata--shows male and female
Species Insectorum, p.436    Fabricius' original description of the species (in Latin)
Works Cited
1.Carlson R.W. () Ichneumonidae catalog
2.Key to the species of Megarhyssa (Hymenoptera, Ichneumonidae, Rhyssinae) in America, north of Mexico
Victoria Pook, Michael Sharkey, David Wahl. 2016. Deutsche Entomologische Zeitschrift 63(1): 137-148.
3.Insects of North Carolina
C.S. Brimley. 1938. North Carolina Department of Agriculture.