Genus: Vespa Linnaeus, 1758
Species: Vespa velutina Lepeletier, 1836
Common names: Asian hornet, yellow-legged hornet, Asian predatory wasp
Vespa velutina is a hornet native to Asia but invasive in Europe. It is a generalist predator of medium- to large-sized insects and will also scavenge vertebrate carrion. It can have significant impacts on flies and social Hymenoptera, such as honey bees. This invasive species threatens honey production and native pollinators. It may be introduced and transported accidentally with soil associated with plants, garden furniture, pots, timber, vegetables, camping equipment, etc. Although Vespa velutina has not been intercepted in North America yet, it is believed to have high invasion potential.
Vespa velutina is widespread in Asia, occurring from northeastern India to Taiwan and as far south as Indonesia (Archer 1994). This species is now established in France and has been found throughout western Europe, including the United Kingdom, the Channel and Balearic Islands, Germany, and Ireland (Monceau et al. 2014).
Distribution map of Vespa velutina by GBIF: https://www.gbif.org/species/1311477
The most recent taxonomic revision of the genus treats all subspecific names in the genus Vespa as synonyms, effectively changing them to informal names for regional color forms. There are 10 recognized color forms (Carpenter and Kojima 1997).
Vespa velutina hunts Apis cerana (the eastern honey bee) in its native range. However, Apis mellifera is preferred because it lacks the defensive behaviors seen in A. cerana (Tan et al. 2007). Vespa velutina also preys on a wide range of large-bodied insects, including dragonflies, flies, and Orthoptera.
After mating in the late fall, new queens find a safe place to hibernate. In the spring the overwintering mated queen emerges and first constructs a paper nest low to the ground. After several months, once there are sufficient workers, they may abandon this nest and build a new one higher in a tree.
Vespa velutina nests are ovoid, with the cell combs enclosed by a paper envelope. They can become enormous, with an average of 6,000 workers. The colony is largest by mid- to late summer, which leads to increased predation on honey bee colonies. This hornet’s nests are annual, with the workers and males dying at the end of the season.
Vespa velutina is invasive in western Europe, South Korea, and Japan. The main color form found in Europe is often referred to as form "nigrithorax," which has been treated as a subspecies in the past.