Rhyssa persuasoria

Rhyssa persuasoria, also known as the sabre wasp, is a species belonging to the family Ichneumonidae subfamily Rhyssinae. Members of this subfamily, including those of Rhyssa and the allied Megarhyssa, are also known collectively as giant ichneumonid wasps or giant ichneumons.

Subspecies
There are four described subspecies of Rhyssa persuasoria:
 * Rhyssa persuasoria himalayensis Wilkinson, 1927
 * Rhyssa persuasoria nepalensis Kamath & Gupta, 1972
 * Rhyssa persuasoria nigrofacialis Meyer, 1922
 * Rhyssa persuasoria persuasoria (Linnaeus, 1758)

Distribution and habitat
This species is present in most of Europe (Austria, Belgium, Great Britain, Russia, Czech Republic, European Turkey, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Norway, Poland, Portugal, Romania, Slovakia, Spain, Sweden, Switzerland, The Netherlands and Yugoslavia), in the Australasian realm, in the Near East, in the Nearctic realm, in North Africa, and in the Indomalayan realm. These wasps normally occur in coniferous or mixed woodland.

Description
Rhyssa persuasoria is one of the largest ichneumon wasps in Europe. The length of adults varies from about 10 - 20 mm in males up to 20 - 40 mm in the females, plus about 20 - 40 mm of the ovipositor. These ichneumon wasps have a thin black body, several whitish spots on the head, thorax, and abdomen and reddish legs. The antennae are long and thin. Females have a long ovipositor, which they use when laying eggs. The length of the ovipositor exceeds the body length.

This species is rather similar to Rhyssa amoena Gravenhorst, 1829.

Biology
Adults can mainly be encountered from July through August, especially in paths and clearings of coniferous forests. They feed on carbohydrates such as sugar and starch, which are obtained, for example, by feasting on honeydew or pine needles. Flowers are not visited.

Female of this parasitic species drills deep into wood by its hair thin ovipositor (terebra) and lays its eggs on larvae living deep in timber (up to 40 mm), which become a food supply and an incubator for the progeny, until it is fully grown. This species has one generation a year (univoltine). Larvae overwinter in the wood, pupating the next spring and emerging from the wood as adults.

Main hosts of Rhyssa persuasoria are the larvae of horntails or wood wasps (Urocerus gigas, Siricidae species, a type of xylophagous sawfly), as well as larvae of longhorn beetles (Spondylis buprestoides, Monochamus sutor) and great capricorn beetle (Cerambyx cerdo). In North America, its main hosts are Sirex areolatus and Syntexis libocedrii.