The median wasp (Dolichovespula media) is a species of social wasp of the family Vespidae found throughout Europe and Asia. It builds aerial paper nests often in shrubs or trees, and occasionally under the eaves of buildings. It is most common to see this wasp between May and October during its 3.3 month colony cycle. Behaviours of this wasp include nest defense, curling which is believed to function in brood incubation, and gastral vibration which is involved in larval feeding. The median wasp has a sex determination system that results in a high level of relatedness within the colony. This species is not usually aggressive but will sting if they feel their nest is threatened. Most foraging in the nest is done by the workers once the first ones reach adulthood. These workers forage for insects, nectar, and wood for nest construction in temperatures as low as . The median wasp is known to be occasionally affected by the fungus Cordyceps sphecocephala and the Cricket paralysis virus. Taxonomy and phylogeny The median wasp was first classified by Anders Jahan Retzius in 1783. It is part of the genus Dolichovespula, a small genus of only 18 social wasp species including species such as the tree wasp (D. sylvestris), the Saxon wasp (D. saxonica), and the parasitic hornet (D. adulterina). This wasp is part of the subfamily Vespinae which include social wasps, social hornets, and yellow jackets. Description and identification D. media is a medium to large species of wasp around in length with yellow and black stripes on its abdomen. It can be identified by its yellow clypeus with a thin black central line and large areas of yellow behind the eyes and on the ocular sinus. The median wasp also has a shiny black thorax with four yellow spots that are tinted orange or red. Queens are often mistaken for hornets due to their reddish colouration, but can be distinguished by their thoracic spots and deep black color. Distribution and habitat The median wasp has a Palearctic distribution and is found throughout Europe and temperate regions of Asia all the way east to Japan. It prefers temperate climates and high humidity. This species was identified in the United Kingdom for the first time in 1980 after having spread there from continental Europe. It has also been sighted in New Zealand, but it is not known if the wasp is widespread