Rhyssa persuasoria, the
Giant Ichneumon, is a species belonging to the family
IchneumonidaeIchneumonidae is a family within the insect order Hymenoptera. Insects in this family are commonly called ichneumon wasps. Less exact terms are ichneumon flies , or scorpion wasps due to the extreme lengthening and curving of the abdomen...
subfamily Rhyssinae.
It is found in most of
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, in the Australasian ecozone, in the
Near EastThe Near East is a geographical term that covers different countries for geographers, archeologists, and historians, on the one hand, and for political scientists, economists, and journalists, on the other...
, in the Nearctic ecozone, in
North AfricaNorth Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
and in the Oriental ecozone.
Rhyssa persuasoria (meaning
persuasive burglar) is one of the largest ichneumon wasp in Europe. The length of adults varies from about 10–20 mm (0.393700787401575–0.78740157480315 ) in males up to 20–40 mm (0.78740157480315–1.6 ) in the females, plus about 20–40 mm (0.78740157480315–1.6 ) of the ovipositor. They have a thin black body, several whitish spots on the head, thorax, and abdomen and reddish legs. The antennae are long and thin. The long stinger on the abdomen of the females is just an egg laying instrument (
ovipositorThe ovipositor is an organ used by some animals for oviposition, i.e., the laying of eggs. It consists of a maximum of three pairs of appendages formed to transmit the egg, to prepare a place for it, and to place it properly...
), therefore these wasps are harmless to humans.
They can mainly be encountered from July through August, especially in paths and clearings of coniferous forests.
Female of this parasitic species drills deep into wood by its hair thin ovipositor (terebra) and lays its grubs on larvae living in timber, which become a food supply and an incubator for the progeny, until it is fully grown. Larvae overwinter, pupating in the next Spring, when they emerge from the wood.
Main hosts of
Rhyssa persuasoria are the larvae of
HorntailHorntail or wood wasp is the common name for any of the 100 non-social species of the family Siricidae, of the order Hymenoptera, a type of xylophagous sawfly...
or Wood Wasps (
Urocerus gigasThe Giant Woodwasp, Banded Horntail, or Greater Horntail is a species of Sawfly, native to the Holarctic and North Africa. Adults are usually between 10 to 40mm in length.Subspecies include:...
, Siricidae species, a type of xylophagous
sawflySawfly is the common name for insects belonging to suborder Symphyta of the order Hymenoptera. Sawflies are distinguishable from most other Hymenoptera by the broad connection between the abdomen and the thorax, and by their caterpillar-like larvae...
), as well as larvae of
Longhorn BeetleThe longhorn beetles are a cosmopolitan family of beetles, typically characterized by extremely long antennae, which are often as long as or longer than the beetle's body...
(
Spondylis buprestoides,
Monochamus sutor) and Great Capricorn Beetle (
Cerambyx cerdo).
Subspecies
- Rhyssa persuasoria var. himalayensis Wilkinson, 1927
- Rhyssa persuasoria var. nepalensis Kamath & Gupta, 1972
- Rhyssa persuasoria var. nigrofacialis Meyer, 1922
External links