Source: http://cjai.biologicalsurvey.ca/bmc_05/key_vespula.html
Timestamp: 2019-04-20 09:09:03+00:00

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This primarily Holarctic and Oriental genus is comprised of 26 species (Carpenter and Kojima 1997, Eck 1998; Dong et al. 2002, 2004; Dong et al. 2005), 13 of which occur in North America (11 in the northeast). Three synanthropic species have been introduced to temperate parts of the southern hemisphere and Hawaii (Carpenter and Kojima 1997) where they are now serious pests.
References. – Eck, 1996 (key to Nearctic species of V. vulgaris-group); Archer, 1989 (key to World species); Akre et al., 1981 (key to Nearctic workers); Jacobson et al., 1978 (key to Nearctic species of V. vulgaris-group); Miller, 1961 (key to Nearctic species excluding V. germanica and V. flavopilosa).
Notes. Species groups according to Carpenter (1987). Extralimital taxon in brackets.
* Note. According to Eck (1996) all three characters mentioned here may be absent in extreme xanthic forms of V. vulgaris. Such specimens appear to occur mostly in the western part of its range and not in the area covered by this key (nevertheless, Eck mentions one aberrant series from Erie, PA). All specimens examined by us key properly through this couplet.
* Note. The difference between the two states is subtle and may prove difficult for the inexperienced user. In worn specimens the original shape of the mandible is difficult to assess.
Note: the socially parasitic V. austriaca has no worker caste.

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