30 : Asian Hornet: Mistaken Identity Key differences between the CASES OF MISTAKEN IDENTITY European hornet and Asian hornet are that the latter is smaller, has characteristic yellow legs, a dark velvety thorax and a dark abdomen with a distinctive The Asian Hornet yellow band on the fourth segment. Asian Hornets are Gay Marris (National Bee Unit) and Helen Roy (NERC Centre never active at night whereas for Ecology & Hydrology) European Hornets may be. Their lifecycle is similar to that of the Asian hornet (and other social ith the threat wasps): of the invasive • mated queens emerge WAsian hornet in early spring and form (Vespa velutina; AH) embryo nests arriving in the UK from • large nests are rapidly continental Europe, established and worker the National Bee Unit hornets attend to the needs (NBU) has been working of the growing colony with colleagues in the • workers are extremely active Non-Native Species and predate a variety of Secretariat (NNSS), the insects to obtain the protein- Centre for Ecology & rich diet that the developing Hydrology (CEH) and Bee hornet brood requires Health Policy (BHP) to • mature hornet nests are raise awareness of this hard to spot, but are most potentially damaging likely to be seen from early predator of honey bees summer Richard Ball Richard and other pollinating The European hornet, Vespa crabro • sexual stages emerge later insects (https://secure.fera. and, if necessary, referred to the This article provides a brief and result in the production defra.gov.uk/beebase/ NBU for confi rmatory diagnosis. overview of some of those species of mated queens index.cfm?pageid=208). People from across the country which comprise cases of mistaken • as the colony dies (in late We have been urging have been very concerned by identity reported since 2011. autumn), these foundresses, all members of the public the threat posed by V. velutina which use high energy (beekeepers or otherwise) to and have responded diligently The European Hornet sugar-rich food sources such report suspect sightings to to the request for information (Vespa crabro) fruits and nectar, seek out the GB Non-Native Species and we have received almost 80 This is the number one case suitable sites in which to Information Portal (GB-NNSIP), suspect reports. Thankfully, to of mistaken identity . There are overwinter led by CEH and hosted by date, all of these have proved probably two reasons for this: • foundresses emerge the NNSS, alert e-mail system (alert_ to be other types of insect, but fi rstly, it is the only native hornet following spring to begin the [email protected]) and are each report is taken seriously. species and, superfi cially, bears cycle again. encouraging the use of hanging We work together, not just some resemblance to V. velutina; traps to monitor for arrival. to rule out that any given secondly, given the fearsome When reporting suspect specimen is V. velutina, but also reputation of the Asian hornet, sightings the public are asked to establish its true identity. there may be a perception that it to provide as much detail as We forward the information to must be a large hornet and the they can about the insect experts (coordinators of national queens of V. crabro are, indeed, they have seen/found and, recording schemes or societies impressive. However, in spite Keep your eyes whenever possible, supply digital hosted by the Biological of the impact of Asian hornets photographs – these are a very Records Centre, www.brc. on other insects and the very open for the useful aid to identifi cation. ac.uk) who compile records of painful stings they may infl ict on Asian hornet. Sightings and alert e-mails are the particular species and so people, they are smaller and less picked up by Dr Helen Roy, the information is extremely physically impressive than their To help, we have principal scientist at the CEH valuable in many regards. European counterpart. details of some www.bee-craft.com of its Junelookalikes 2013 Vol 95 No 6 Asian Hornet : 31 Notable differences: thought to feed on nest debris. • Larger than the Asian The striking and large adults (the wingspan can be as much (Below) Sirex hornet species with exit as 45 mm) are typically reported • Abdomen has more yellow hole from timber stripes than AH to us between June and • Legs darker than AH October. Harmless to humans, they can be seen in a variety of Lloyd Harper The Hoverfl y (Volucella habitats (urban, suburban or rural) including parks, gardens, (Above) Female giant woodwasp, zonaria) Urocerus gigas scrubland, heaths and woods, Volucella zonaria is actually where adults visit fl owers. reported to us as a suspect Asian known as the ‘hornet mimic hornet is Urocerus gigas, also hoverfl y’, so we can hardly be Notable differences: known as the Giant Woodwasp, • Species of fl y surprised that it accounts for a Banded Horntail or Greater • One pair of wings (AH and fair number of cases of mistaken Horntail. This relatively common Fera, Crown Copyright other hornets and wasps identity. Seventy years ago it species is usually seen on the have two pairs) was considered to be very rare wing between May to October, UK alone) includes some quite • Associated with wasps in the UK, with only a couple in or near coniferous forests. large and conspicuous insects, in nests but doesn’t form of specimens recorded prior to We have also received sightings particular members of the family paper nests of its own the 1940s (fi rst report 1901). of Sirex (most probable species Ichneumonidae. • Larger than the Asian However, its range has since noctilio). Native to Europe, Some species of ichneumon hornet spread and sightings in southern northern Africa and Asia, adults wasps lay their eggs in the • Abdomen has more yellow England are not uncommon. vary in length from 9 mm to ground, but the majority are stripes than AH 36 mm, the females being parasitic on other insect species. • Legs darker than AH. especially long. These exclusively The female lays one or more use pine trees as their hosts. eggs (the number depends on Woodwasps the species in question) into Notable differences: or onto the body of her host, We have been sent several Urocerus gigas which is typically a larva or a photographs of ‘woodwasps’ or • Horn-like protrusion on pupa (again, the life stage and ‘horntails’, the names commonly fi nal abdominal segment host species used depends on Alvesgaspar used to collectively identify the • Females have long, the ichneumon). non-social xylophagous (ie, conspicuous ovipositor In the UK, large examples wood boring/feeding) sawfl ies. • Lay eggs into wood/timber Adult hornet mimic hoverfl y, include the genera Megarhyssa A typical adult woodwasp is • Larger than the Asian Volucella zonaria (which parasitises larvae of the brown, blue or black with yellow hornet wood-boring horntails [see It has been suggested that parts and may often reach up to • Abdomen has more yellow above]) and Pimpla, which V. zonaria, rather than being 4 cm long. Being so large in size, stripes than AH lays eggs into the pupae of permanently established in they are certainly impressive. Sirex species butterfl ies and moths. The the UK, only becomes resident They are related to ‘true’ wasps • Horn-like protrusion on the body of a female Megarhyssa, when particular weather but are harmless to humans. fi nal abdominal segment including her ovipositor, can be conditions result in ‘substantial The female’s long ovipositor at • Females have long, 40 mm long. Female Pimpla are infl uxes’ from continental the rear is used for laying eggs conspicuous ovipositor shorter (20–30 mm in length), Europe; this would explain the into timber/tree trunks, etc, in • Lay eggs into wood/timber markedly fl uctuating numbers which the immature stages of • Larger than the Asian Adult female Pimpla found in the UK from year to the woodwasp complete their hornet hypochondriaca year and the periodic, large development. They typically • Abdomen has more yellow accumulations sometimes migrate to just under the bark stripes than AH. found in coastal areas (in the before pupation. Depending on Netherlands). the species in question, this can Regarding its biology, the take as long as fi ve years and Ichneumon Wasps immature stages of V. zonaria sometimes results in the adult Apart from the woodwasps, develop inside colonies of emerging from timber that has parasitic wasps are another European social wasp species, been used in construction or type of related insect. This very Vespula vulgaris and V. even to build furniture! diverse insect group (comprising germanica, where they are The species most frequently several thousand species in the Fera), Crown Copyright) Fera), Crown June 2013 Vol 95 No 6 www.bee-craft.com 32 : Asian Hornet: Mistaken Identity The Median wasp, chances of eradication before please contact Bee Health at Dolichovespula media it can establish and spread. [email protected] This is making a signifi cant BWARS contribution to the security, not The Bees, Wasps and Ants just of our honey bee stocks, Recording Society (BWARS) is but to other unmanaged the national society dedicated insect pollinators predated by to studying and recording these Nigel Jones V. velutina. species (aculeate Hymenoptera) Please continue to be vigilant in Britain and Ireland. You can The Median Wasp and please do forward all fi nd additional information Claire Waring sightings of concern, esven about species mentioned in Although not reported as a if you are in doubt about this article on their website The Common wasp, Vespula case of mistaken identity, the vulgaris, feeding on grapes the identifi cation.