''Megarhyssa macrurus'', also known as the long-tailed giant ichneumonid wasp or long-tailed giant ichneumon wasp, is a species of large

ichneumon wasp The Ichneumonidae, also known as the ichneumon wasps, Darwin wasps, or ichneumonids, are a family of parasitoid wasps of the insect order Hymenoptera. They are one of the most diverse groups within the Hymenoptera with roughly 25,000 species cu ...

. It is a parasitoid, notable for its extremely long ovipositor which it uses to deposit an egg into a tunnel in dead wood bored by its host, the larva of a similarly large species of

horntail Horntail or wood wasp are any of the 150 non-social species of the hymenopteran family Siricidae, a type of wood-eating sawfly. The common name "horntail" derives from the stout, spine-like structure at the end of the adult's abdomen, which is u ...

Etymology

The specific epithet of ''macrurus'' is from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

words ' () meaning "long", and ' () meaning tail.

Description

''Megarhyssa macrurus'' has a reddish-brown body of up to long. It has black and yellow-orange stripes.Pigeon Tremex Horntail and the Giant Ichneumon Wasp
Ext.colostate.edu (2010-05-12). Retrieved on 2010-12-17. Its wings are transparent and the body elongated. The body and ovipositor together can be more than long in the female. Males are smaller and have no ovipositor.

The ovipositor

The ovipositor looks like a single filament, but it comprises three filaments, the middle one of which is the actual ovipositor, which is capable of drilling into wood. This central filament also appears to be a single filament, but is made of two parts, with a cutting edge at the tip. The two parts interlock and slide against each other. Although very thin, the ovipositor is a tube and the egg being laid moves down a minute channel in its center. The outer two filaments are sheaths which protect the ovipositor; they arc out to the sides during egg-laying.

Distribution

''M. macrurus'' is found across the eastern half of the United States, reaching into the extreme south of Canada near the

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lak ...

Behaviour

Pigeon tremex Tremex columba 5284079-PPT

''M. macrurus'' is harmless to humans; they are parasitoids on the larvae of the pigeon horntail (''

Tremex columba ''Tremex columba'', also known as the pigeon tremex or pigeon horntail, is a species of horntail that is native to eastern and western North America. Appearance and behavior The females are larger than the males, with females growing to 25- ...

'', Symphyta), which bore tunnels in decaying wood.Ichneumon wasp
. Insects.tamu.edu. Retrieved on 2010-12-17. Female ''Megarhyssa macrurus'' are able to detect these larvae through the bark; they paralyse them and lay their eggs on the living but paralysed larva; within a couple of weeks the Megarhyssa larvae will have consumed their host and pupate, emerging as an adult the following summer.

Subspecies

Subspecies include:Essig Museum of Entomology Collections
Essigdb.berkeley.edu. Retrieved on 2010-12-17. *'' M. m. icterosticta'' Michener, 1939 *'' M. m. lunator'' (Fabricius, 1781) - considered a synonym of ''M. m. macrurus'' by Carlson (1979) *'' M. m. macrurus'' (Linnaeus, 1771)

References

External links

High quality images of ''Megarhyssa macrurus''Videos of ''Megarhyssa macrurus'' Ovipositing
{{Taxonbar, from=Q6808833 Ichneumonidae Hymenoptera of North America Insects described in 1771 Taxa named by Carl Linnaeus