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Species Megarhyssa greenei - Greene's Giant Ichneumonid Wasp

Ichneumon Wasps - Megarhyssa greenei - female Wasp ID [Megarhyssa? greenei??] Request - Megarhyssa greenei - female looks like a cross between mosquito and wasp? - Megarhyssa greenei - female insect999640 - Megarhyssa greenei - male Male Megarhyssa greenei? - Megarhyssa greenei - male Megarhyssa greenei - female Giant Ichneumon - Megarhyssa macrurus - Megarhyssa greenei - female Megarhyssa cf. greenei - Megarhyssa greenei - 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 greenei (Greene's Giant Ichneumonid Wasp)
Synonyms and other taxonomic changes
Megarhyssa greenei Viereck, 1911
=Megarhyssa greenei floridana Townes, 1960(1)
=Megarhyssa greenei greenei Viereck, 1911
Explanation of Names
Megarhyssa greenei Viereck, 1911
greenei = named after George M. Greene, an American entomologist and former secretary of the Entomological Section of the Academy of Natural Sciences of Philadelphia
Females are distinguished from those of M. macrurus by having the forewing clear (unpigmented) along the basal vein (such that a single black spot is present) and by the shorter ovipositor length (the shortest in all US species of Megarhyssa). In live specimens, this is only about 1.5x the body length (1.8x forewing length). Those of M. greenei also have a more extensively yellow face, lacking vertical lineations.(2)

Males are noted by their entirely clear wings, red and yellow mesopleuron(2), and red hind femur.(3)
e NA to Great Plains (BG data)
mostly May-Sept (BG data)
Larval host: larvae of Tremex columba (pigeon horntail).
Specimens from the southeastern US are highly variable in terms of yellow markings. Townes described two subspecies, but Carlson found that the extent of geographic variation is not conducive to the recognition of subspecies.(1) BugGuide records have also revealed a third color form from this area that wasn't treated under Townes' subspecies divisions.

widespread eastern US, formerly M. g. greenei: red with minor yellow markings on the thorax, paired lines on the mesoscutum, and narrow chevrons on the abdomen; wings hyaline with a single spot of dark pigmentation

Florida (with intermediates in South Carolina and Alabama, photo #2), formerly M. g. floridana: yellow markings more restricted on the mesoscutum and abdomen; wings almost uniformly dark

Georgia, North Carolina and Maryland, no separate name: yellow markings more extensive on the thorax, abdominal markings developed into spots; wings hyaline with a single spot of dark pigmentation
See Also
Megarhyssa macrurus females have additional pigmentation in the wings, dark vertical lines on the face, and a longer ovipositor of about 2.3x the body length (3x forewing length). Range: e. NA to Rocky Mtns.

Specimens from Florida are highly convergent to the coloration of Labena grallator females. The latter differs in lacking the striations on the mesoscutum distinctive of Rhyssinae, the narrower first abdominal segment, and orange-yellow color of the ovipositor sheath distinctive of our Labeninae. Range: e. NA to Rocky Mtns. and se. CA
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.Giant Ichneumon