Vespula austriaca

Vespula austriaca is a parasitic wasp, parasitising the nests of other species in the genus Vespula, and with a Holarctic distribution. It is sometimes called the red cuckoo wasp in Europe or cuckoo or boreal yellowjacket in North America.^[2]

Description

A largely black wasp with yellow markings. The underside of its scape is yellow, as opposed to all black. This is the only species in the genus Vespula which has long erect hairs along the hind tibia.^[3]

Biology

Vespula austriaca is a rarely collected species which is an obligatory social parasite of the red wasp V. rufa within the palearctic portion of its distribution. It does not possess a worker caste and is dependent on host workers to rear its brood of new males and queens. In North America V. austriaca is sympatric with a number of potential hosts from the Vespula rufa group;^[4] however, in 1978, two colonies of V. acadica, each containing a V. austriaca queen, were collected near the small town of Harvard in northern Idaho. These represent the first records of V. austriaca being taken from nests of a North American Vespula species.^[5]

V. austriaca usurps the host queen and in experiments it was shown that there was no peaceful coexistence period with the host queen, and the invading queen was immediately aggressive to the host. The host queen was victorious in almost all fights with the invading queen during the queen nest stage. However, after worker emergence the queen's behaviour changed and she no longer vigorously defended the nest. The invading queen killed a third of the workers in the colony and drove the queen from the nest before physically dominating the remaining workers.^[6]

Distribution

Holarctic. In North America from Alaska south to New Mexico, Arizona and California in the west and New Jersey in the east. Widespread in Palaearctic region from Europe to Kamchatka, Japan and northwest China, south to Turkey, northern Pakistan and northern India.^[7]

References

Wikispecies has information related to: Vespula