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The species of paper wasps in the tribe Vespini, family Vespidae from America North of Mexico are reviewed, including a new identification key to the genera and species, complete synonymy, distribution and biology. This fauna includes six species of Dolichovespula Rohwer, three species of Vespa Linnaeus and 13 species of Vespula Thomson. No Holarctic species are recognized, with the result that Dolichovespula arctica (Rohwer) and Vespula intermedia (du Buysson) are again recognized as species, while Vespula infernalis (de Saussure) is given new status as a species.
Vespa, Dolichovespula, Vespula
Vespinae, or the yellow jackets and hornets, are among the most recognizable wasps in North America. All of the species are either social or are social parasites of other congeners. They construct their nests out of a mixture of plant fibers and salivary secretions, and the nests can range from baseball-sized, with a few thousand cells, to nests with hundreds of thousands of cells. Nests are generally annual but a few species will develop large perennial nests in warm climates. A number of species, such as Vespula alascensis and Vespula germanica, are considered to be pests because of their willingness to build nests in structures and to scavenge a variety of food materials other than live insects, which brings them into frequent contact with humans and because the majority of sting-caused deaths are attributable to yellow jackets.
There have been a number of changes in the North American social vespine fauna since the widely used key published by
Given these changes, and the difficulty of using many of the existing keys, which rely heavily on coloration, we have developed a new key incorporating these taxonomic changes and attempting to place more emphasis on structural features, such as male genitalia. The key by
North America as construed here is America north of Mexico. Thus two species recently described from central Mexico (Vespula inexspectata Eck;
Specimens used in the development of this key were from the collections of the American Museum of Natural History, New York; Bohart Museum of Entomology, University of California, Davis; California State Collection of Arthropods, California Department of Food & Agriculture, Sacramento, and the U. S. National Museum of Natural History, Washington, D. C.
Type repositories listed in the synonymies include: BUDAPEST – Hungarian Natural History Museum, Budapest; CAMBRIDGE – Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA; COPENHAGEN – Zoologisk Museum, Universitetsparken, Copenhagen, Denmark; DRESDEN – Staatliches Museum für Tierkunde, Dresden, Germany; GAINESVILLE – Florida State Collection of Arthropods, Gainesville, USA; GENEVA – Museum of Natural History, Geneva, Switzerland; GENOA – Museo Civico di Storia Naturale “Giacomo Doria”, Génova, Italy; LEIDEN – Rijksmuseum van Natuurlijke Historie, Leiden, Netherlands; LINNAEAN SOCIETY – Linnaean Society, London, UK; LONDON – The Museum of Natural History, London, UK; OTTAWA – Canadian National Collection of Insects, Agriculture Canada, Ottawa; OXFORD – Hope Entomological Collections, Oxford University, England; PARIS – Muséum National d’Histoire Naturelle, Paris, France; PHILADELPHIA – Academy of Natural Sciences, Philadelphia, Pennsylvania, USA; ST. PETERSBURG – Zoological Institute, St. Petersburg, Russia; STOCKHOLM – Naturhistoriska Riksmuseet, Stockholm, Sweden; TAICHUNG – National Museum of Natural Sciences, Taichung, Taiwan; TURIN – Instituto di Zoologia Sistematica, Universita di Torino, Turin, Italy; UPPSALA – Uppsala University Zoological Museum, Uppsala, Sweden; WASHINGTON - U. S. Museum of Natural History, Washington, D. C., USA.
Key to the Yellow Jackets and Hornets of North America1 | Head in dorsal view greatly expanded behind eyes, postocular distance more than twice as broad as distance between hindocelli (as in Fig. 5); Vespa Linnaeus | 2 |
– | Head in dorsal view not expanded behind eyes, postocular distance subequal to distance between hindocelli (as in Figs 6, 7) | 4 |
2 | Metasomal segments I and II orange or red, posterior segments black, without sublateral free or connected blackish spots (Fig. 26); metapleural punctures ventrally well-defined, nearly contiguous; southern California? | Vespa affinis (Linnaeus) |
– | Metasomal segments basally blackish to brown and apically yellow; metapleural punctures ventrally shallow, separated by 1 puncture diameter or more | 3 |
3 | Female clypeal punctures clearly defined, contiguous or nearly so; male metasomal sterna VI-VII apicomedial margin straight or shallowly indented; metasomal terga III–VI transverse basal black band with sublateral free or connected black spot (Fig. 27); eastern United States | Vespa crabro Linnaeus |
– | Female clypeal punctures medially, shallow, separated by 1 puncture diameter or more; male metasomal sterna VI-VII apicomedial margin deeply emarginate; metasomal terga III transverse basal black band simple, barely undulating (Fig. 28); British Columbia? | Vespa simillima (Smith) |
4 | Malar space long, one fifth eye height or longer (Figs 2, 9); pronotum with transverse anterodorsal carina; Dolichovespula Rohwer | 5 |
– | Malar space short, one-tenth eye height (Figs 4, 10); pronotum without transverse anterodorsal carina; Vespula Thomson | 10 |
5 | Metasomal terga I-III entirely black (Fig. 33); pronotal lateral angle finely rugose; widespread | Dolichovespula maculata (Linnaeus) |
– | Metasomal terga I-III with pale markings; pronotal lateral angle not rugose | 6 |
6 | Occipital carina absent; female clypeal apical margin acutely angulate; male apical flagellomeres without tyloids; Alaska to Newfoundland, south to Arizona, North Carolina, Georgia | Dolichovespula arctica (Rohwer) |
– | Occipital carina present; female clypeal apical margin with obtuse to right angles; male apical flagellomeres with tyloids | 7 |
7 | Body, particularly face, with whitish markings, metasomal terga I-II often with lateral red spots (Fig. 29); Alaska, Maine and northern Canada | Dolichovespula albida (Sladen) |
– | Body, particularly face, with yellow markings, usually without red metasomal spots; more southern distribution | 8 |
8 | Metasomal terga I and II broad yellow bands expanded medially into sharp, triangular projection (Fig. 32); genal band continuous, less commonly medially broken; widespread species | Dolichovespula arenaria (Fabricius) |
– | Metasomal terga I and II with narrow, parallel-sided yellow bands, sometimes slightly narrowed medially; genal band integrity variable | 9 |
9 | Malar space length one-fourth eye height; clypeal apex width 1.5–1.6× malar space length; male apical flagellomeres with two tyloids; Alaska to Newfoundland, south to Colorado, Georgia | Dolichovespula norvegicoides (Sladen) |
– | Malar space length one-fifth eye height; clypeal apex width 1.9–2.0× malar space length; male apical flagellomeres with one or two tyloids; western North America, Alaska and Alberta south to Arizona | Dolichovespula alpicola Eck |
10 | Female; six metasomal segments; 10 flagellomeres | 11 |
– | Male, seven metasomal segments; 11 flagellomeres | 23 |
11 | Scutum with two fully developed longitudinal yellow stripes (as in Fig. 11); metasomal sterna I-V with few if any black markings | 12 |
– | Scutum without stripes, if stripes present only partly developed; metasomal sterna with extensive black markings | 13 |
12 | Metasomal terga II-IV with small oval sublateral black spots (Fig. 46); supraantennal black mark as broad or broader than antennal socket (Fig. 24); primarily from California, with small populations in Arizona, Nevada, Oregon and Baja California, Mexico | Vespula sulphurea (de Saussure) |
– | Metasomal terga II-IV without small oval sublateral black spots (Fig. 45); supraantennal black mark narrower thanantennal socket (Fig. 25); mostly east of 100th meridian but extending through Texas to Guatemala | Vespula squamosa (Drury) |
13 | Pale body markings whitish; metasomal tergum II pale apical band narrow and parallel-sided (as in Figs 38, 42) | 14 |
– | Body markings yellow; metasomal tergum II pale apical band usually broad and sinuous or emarginated medially (as in Figs 41, 43) | 15 |
14 | Metasomal terga I and II with reddish markings, tergum I extensively red, with posterior whitish band along apical margin, usually with partial transverse whitish band at apex of anterior face (Fig. 42); Alaska to Newfoundland, south to Vermont | Vespula intermedia (du Buysson) |
– | Metasomal terga I and II without reddish markings; tergum I black, with partial white band along posterior margin and often partial white band at apex of anterior face (Fig. 38); Canada and northern United States, south to Colorado and Georgia | Vespula consobrina (de Saussure) |
15 | Eye dorsally margined by continuous yellow band (Figs 10, 23), sometimes narrowly broken; metasomal tergum I with diamond-shaped medial black mark | Vespula pensylvanica (de Saussure) |
– | Eye not dorsally margined by yellow band on (as in Figs 15, 16), metasomal tergum I with or without diamond-shaped medial black mark | 16 |
16 | Hindtibia with long black setae; clypeal apical angles acute in females (Fig. 20); northern North America, south to Arizona, New Jersey | Vespula infernalis (de Saussure) stat. n. |
– | Hindtibia without long black setae; clypeal apical angles blunt in females (as in Fig. 16) | 17 |
17 | Scape yellow ventrally | 18 |
– | Scape without yellow ventrally, although may be dark brown ventrally | 20 |
18 | Metasomal tergum II largely black, irregularly parallel-sided, with narrow apical yellow band and without sublateral yellow spot or spot faint (Fig. 47); northeastern North America south to Georgia and Alabama, west to Iowa | Vespula vidua (de Saussure) |
– | Metasomal tergum II black band apically lobate, with broad apical yellow band as broad or broader than apical bands on III-V, and usually with sublateral yellow spot (as in Figs 35, 37) | 19 |
19 | Metasomal tergum II black band angulate medially; gena with continuous yellow band in side view, sometimes interrupted by black spot or narrow medial interruption (Fig. 37) | Vespula atropilosa (Sladen) |
– | Metasomal tergum II black band broadly rounded medially, often having free lateral yellow spots; gena with yellow band broadly interrupted by black spot, rarely continuous (Fig. 35) | Vespula acadica (Sladen) |
20 | Supraantennal black band as broad or broader than antennal socket; gena with yellow band broadly interrupted by black spot in side view | Vespula alascensis (Packard) |
– | Supraantennal black band much narrower than antennal socket; gena with yellow band uninterrupted or narrowly broken in side view | 21 |
21 | Metasomal tergum I with diamond-shaped or somewhat broader medial black mark, attachment to anterior black band no narrower than one-third of width (Fig. 40) | Vespula germanica (Fabricius) |
– | Metasomal tergum I with nearly free broadly diamond-shaped or triangular black mark or black mark broadly attached to anterior band | 22 |
22 | Metasomal tergum I with anchor-shaped medial black mark, narrowly connected to anterior black band, if melanistic with at least pair of transverse yellow spots present (Fig. 43) | Vespula maculifrons (Buysson) |
– | Metasomal tergum I with triangular medial black mark, broadly connected to anterior black band (Fig. 39) | Vespula flavopilosa Jacobson |
23 | Paramere dorsomedial margin evenly convex, without well-developed acute tooth or angle (as in Fig. 78A); volsella without large, densely setose digitus (as in Fig. 78) | 24 |
– | Paramere dorsomedial margin with well-developed tooth or angle (as in Fig. 80A); volsella with large, densely setose digitus extending nearly as long as aedeagus, visible as dense brush of long setae at apex of genital capsule (as in Fig. 80) | 31 |
24 | Scutum with two longitudinal yellow stripes (as in Fig. 11) | 25 |
– | Scutum without longitudinal yellow stripes | 26 |
25 | Aedeagus elongate, strongly exserted beyond apex of paramere by one-half of paramere length or longer (as in Figs 71, 78) | Vespula sulphurea (Saussure) |
– | Aedeagus short, broad, exserted beyond apex of paramere by one-third of paramere length or less (Figs 70, 77) | Vespula squamosa (Drury) |
26 | Body with pale markings whitish | 27 |
– | Body with pale markings yellow | 28 |
27 | Basal metasomal segments without red markings (Fig. 38) | Vespula consobrina (de Saussure) |
– | Basal metasomal segments with red markings (Fig. 42) | Vespula intermedia (du Buysson) |
28 | Metasomal tergum I with diamond-shaped medial black mark, tergum II with broad irregularly lobate posterior yellow band (Fig. 37) | Vespula atropilosa (Sladen) |
– | Metasomal terga I and II with narrow subparallel-sided posterior yellow band (as in Fig. 35) | 29 |
29 | Clypeus with large medial black spot or stripe (Fig. 14) | Vespula acadica (Sladen) |
– | Clypeus without single medial black spot or black spot small irregular (as in Fig. 20) | 30 |
30 | Hindtibia without long black setae; clypeal apical angle obtusely angulate | Vespula vidua (de Saussure) |
– | Hindtibia with long black setae (even rubbed specimens have a few); clypeal apical angle blunt but well-developed (Fig. 20) | Vespula infernalis (de Saussure) |
31 | Metasomal tergum I with diamond shaped medial black mark narrowly connected to black band (as in Figs 40, 44) | 32 |
– | Metasomal tergum I with parallel-sided black band, black band with triangular medial projection, broadly attached to rest of band (as in Figs 36, 39) | 34 |
32 | Aedeagus without lobe or process behind apex (Fig. 69, 80); eye usually margined by continuous yellow band (as in Fig. 10) or yellow band broken by narrow black line dorsally (may be more broadly interrupted in some males) | Vespula pensylvanica (Saussure) |
– | Aedeagus with short rounded (germanica, Fig. 67) or pointed (maculifrons, Fig. 68) process behind apex; eye with yellow marginal band always broadly broken dorsally | 3 |
33 | Metasomal tergum VII undulate, rounded dorsally in lateral view (Fig. 13); metasomal terga II-IV with free sublateral black spot or spot narrowly connected to black band (Fig. 40) | Vespula germanica (Fabricius) |
– | Metasomal tergum VII step-like in lateral view, angulate dorsally in lateral view (Fig. 12); metasomal terga II-IV without free or narrowly connected sublateral black spots (Fig. 43), if melanistic with at least pair of transverse yellow spots present | Vespula maculifrons (du Buysson) |
34 | Supraantennal black band much narrower than antennal socket at least medially; metasomal terga II-V with strongly trilobate black band (Fig. 39) | Vespula flavopilosa Jacobson |
– | Supraantennal black band as wide or wider than antennal socket; metasomal terga II-V with black band parallel-sided or weakly lobate (Fig. 36) | Vespula alascensis (Packard) |
Vespula (Dolichovespula)
Pseudovespa (Pseudovespula)
Dolichovespula (Boreovespula)
Dolichovespula (Metavespula)
http://species-id.net/wiki/Dolichovespula_albida
Figs 29, 48This species occurs in the Hudsonian Zone of North America from Alaska to Maine.
Dolichovespula albida was split again from Dolichovespula norwegica (Fabricius) by Carpenter et al. (2012). The nests are generally small and may be subterranean (
http://species-id.net/wiki/Dolichovespula_alpicola
Figs 30, 49, 54This is a northern boreal species found in western North America from Alaska to Alberta, and extending as far south as Arizona and New Mexico along the Rocky Mountains (R. Jacobson personal communication).
Dolichovespula alpicola is generally found in mixed hardwood-conifer forests in mountainous regions. There is little information on the nesting biology in this species.
http://species-id.net/wiki/Dolichovespula_arctica
Figs 31, 50, 55It occurs as far south as California, Arizona and Georgia in North America. Pale markings can be yellow or whitish in Dolichovespula arctica.
This species is an obligatory social parasite of Dolichovespula arenaria (
http://species-id.net/wiki/Dolichovespula_arenaria
Figs 32, 51, 56This species is abundant throughout boreal North America.
Dolichovespula arenaria feeds on live prey but will occasionally visit carrion. It builds aerial nests, like Dolichovespula maculata, but its nests are usually built in more sheltered sites, such as within bushes, trees, on houses and outbuildings, and rarely even under rocks.
http://species-id.net/wiki/Dolichovespula_maculata
Figs 2, 6, 9, 33, 52, 57The species occurs throughout North America.
This is the only Dolichovespula in North America with the anterior part of the metasoma completely black, and the pale markings are always whitish. It builds aerial nests, which are usually found in exposed places such as hanging from tree branches. These wasps usually feed on live prey, particularly spiders and flies.
http://species-id.net/wiki/Dolichovespula_norvegicoides
Figs 34, 53, 58Dolichovespula norvegicoides is relatively rarely collected, although it occurs widely throughout northern North America and further south along mountain ranges.
This species builds small, aerial nests.
Vespula germanica worker a side view b dorsal view; Vespula pensylvanica worker c side view d dorsal view.
11–12 Front view of face 5–7 Dorsal view of head 8–10 Lateral view of head 11 Dorsal view of thorax 12, 13 Lateral view of male metasomal tergum VII.
Front view of face, antennae removed. Vpl. = Vespula.
Vespa Linnaeus, 1758:343, 572. Type species: “Vespa crabro Fabricius” (=Vespa crabro
Macrovespa
Vespa (Nyctovespa)
http://species-id.net/wiki/Vespa_affinis
Figs 5, 26There is a single report of a colony of this Asian species in North America, from San Pedro, in Los Angeles Co., California in 2010 (LSK, personal observation). It is not clear if the species has become established in California. It has also been introduced into New Zealand. Its native range is from India to the Bismarck Islands.
In Asia, Vespa affinis builds large aerial nests of up to several thousand workers (
http://species-id.net/wiki/Vespa_crabro
Fig. 27The central European color form of this Palearctic species was introduced into the New York area in the mid-1800’s (de
Nests are generally built in above-ground cavities, wall voids, hollow trees, and even in abandoned honey bee hives. Nests are large in size because of the size of the wasps but generally contain only a few thousand cells. These wasps feed on live insects, including honey bees near hives (
http://species-id.net/wiki/Vespa_simillima
Figs 3, 8, 28This East Asian species was introduced into British Columbia, Canada but has apparently not become established. We have included it in this review because of the potential for a reintroduction.
Nests are built in a wide variety of situations including in bushes, underground cavities, hollow trees, under eaves, in attics, on rock walls, and in wall voids. As with the other Vespa species affinis is predatory on other insects, including honey bees.
Dorsal view of worker metasoma.
Dorsal view of worker metasoma.
Lateral view of genital capsule in Dolichovespula (Dolichovespula) 54–58 Ventral view of genital capsule.
Vespa (Vespula)
Vespa (Pseudovespa)
Dolichovespula (Paravespula)
Paravespula (Allovespula)
Vespula (Rugovespula)
http://species-id.net/wiki/Vespula_acadica
Figs 14, 35, 59, 72This is primarily a boreal species, occurring across subArctic Canada and southern Alaska. Its range extends further south in the Rocky, Sierra, Cascade, Siskiyou and Appalachian mountains.
Vespula acadica feeds on live insects and builds small subterranean nests.
http://species-id.net/wiki/Vespula_alascensis
Figs 15, 36, 65, 81Widespread in North America
Vespula alascensis nests are usually built in subterranean cavities or in structures. The nests can be huge and may become perennial in warmer climates. This species feeds on live prey but will scavenge any source of protein or sugar. It has been introduced into Hawaii, but is not now established (
This North American species was usually known as Vespula vulgaris (Linnaeus), based on the similarity between the American and European populations.
http://species-id.net/wiki/Vespula_atropilosa
Figs 16, 37, 60, 73Vespula atropilosa occurs in mountain regions from the Rocky Mountains west.
This species builds subterranean nests, preferring open areas, including pastures and golf courses. It is predatory on other insects.
http://species-id.net/wiki/Vespula_consobrina
Figs 17, 38, 61, 74Vespula consobrina occurs in the Canadian and Transition Zones of northern and central North America.
This predatory species preys on live insects and usually nests in cavities, using sites in logs, wall voids and rodent burrows.
http://species-id.net/wiki/Vespula_flavopilosa
Figs 18, 39, 66, 82Vespula flavopilosa occurs in the eastern United States as far south as Georgia (R. Jacobson, personal communication).
It builds subterranean nests. This species feeds on live insects, as well as other sources of sugar and protein, and is a scavenger much like Vespula germanica, Vespula pensylvanica and Vespula alascensis.
http://species-id.net/wiki/Vespula_germanica
Figs 1a, b, 13, 19, 40, 67, 83Vespula germanica has been unintentionally introduced into temperate regions worldwide. It apparently first appeared in Montreal in the 1960’s and other parts of eastern North America in the 1970’s, although there is a record of the species collected in Ithaca, New York in 1891 (
The nests are usually built in structures or less commonly in the ground. Nests can be huge and may become perennial in warmer climates. These wasps feed on live prey or scavenge any source of protein or sugar.
http://species-id.net/wiki/Vespula_infernalis
Figs 4, 7, 20, 41, 62, 75The distribution of Vespula austriaca closely resembles that of acadica, occurring in subarctic Alaska and Canada, and southward in the western mountain ranges.
This is an obligatory social parasite of Vespula acadica (
http://species-id.net/wiki/Vespula_intermedia
Figs 21, 42, 63, 76These wasps occur in the far northern Nearctic Region.
The biology of North American intermedia has not been studied. Vespula rufa in the Palearctic usually nests below ground, in cavities or under eaves. They prey on live insects.
Although treated as a synonym of Vespula rufa (Linnaeus), which is thus a Holarctic species, the North American population is probably distinct and should be treated as a separate species, Vespula intermedia (du Buysson). It differs in coloration from Vespula rufa, with the pale markings being whitish and the metasomal terga I-II with reddish markings. The pale markings are either yellow in Vespula rufa (European specimens), or the terga lack reddish markings (Eastern Palearctic), or there are whitish spots in addition to reddish markings (Eastern Palearctic).
http://species-id.net/wiki/Vespula_maculifrons
Figs 12, 22, 43, 68, 84This species is the most common Vespula occurring east of the 100th meridian.
It builds subterranean nests in a wide variety of situations, even in abandoned vehicles. These yellow jackets prey on live insects and are also scavengers of sources of protein and sugar.
http://species-id.net/wiki/Vespula_pensylvanica
Figs 1c, d, 10, 23, 44, 69, 80This is the most abundant pest species of Vespula on the West Coast and much of the interior west of North America.
Nests are usually built in cavities, which may be in the ground or in structures, such as attics, wall voids and even basements. The nests can become huge and often become perennial in warmer climates. These wasps are general scavengers, and will feed on live prey or any other source of protein or sugar including garbage. It is adventive in Hawaii.
http://species-id.net/wiki/Vespula_squamosa
Figs 25, 45, 70, 77This is an eastern species, occurring east of the 100th meridian and south to Honduras.
It is a facultative social parasite of Vespula maculifrons. The two striped scutum is a distinctive feature of both Vespula squamosa and Vespula sulphurea. Queens of squamosa are quite different in color from workers and males, with their extensive orange-brown coloration, particularly on the metasoma.
http://species-id.net/wiki/Vespula_sulphurea
Figs 11, 24, 46, 71, 78Vespula sulphurea is abundant in mid elevation and wildland areas in western North America.
This is the yellowest of the North American species, with a two yellow-striped scutum much like that seen in Vespula squamosa, but sulphurea occurs west of the 100th meridian. They build small, subterranean nests, generally feed on live prey; in unusual circumstances they might scavenge food.
http://species-id.net/wiki/Vespula_vidua
Figs 47, 64, 79Vespula vidua occurs in the Transition and Upper Austral Zones of eastern North America.
Most nests are subterranean but Vespa vidua will also build nests in hollow logs.
Lateral view of genital capsule in Vespula (Vpl). Abbreviations: ae = aedeagus p = paramere.
Ventral view of genital capsule in Vespula (Vpl). Abbreviations: A. = dorsal view of paramere ae = aedeagus p = paramere v = volsella Vpl. = Vespula.
JMC acknowledges the support of National Science Foundation Grant DEB-0843505. The manuscript was greatly improved by comments and suggestions from Michael Archer and Bob Jacobson.