Gasteruption assectator (Linnaeus, 1758) (Parasitic Wasp)
Commonly known as the Wild Carrot Wasp.
Family: Gasteruptiidae.
Length: 8 to 12mm
Season: May to September.
Gasteruption assectator is a common parasitic wasp and found over most of Europe, as far north as Sweden. They are kleptoparasites of stem-nesting aculeate. In the images below shows the female having a very long ovipositor. The length being an advantage as sometimes the host will be positioned deep in a semi hardened plant stem, or in wooden crevasses; so making it possible for her to deposit her egg onto a host. Will also visit various nests of various solitary bees and wasps, depositing her egg, on or near to the hosts eggs. When her eggs hatch, they will immediately feed on the grubs of the host and will also feed on the stored provisions, intended for the hosts young.
Habitat: Woodlands, woodland edges, meadows and often seen feeding on flowers or investigating around rotting wood and around nests of solitary bees and wasps.