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Species guide - species detail

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Ancistrocerus waldenii (Potter wasp)



Ancistrocerus waldenii is a species of wasp is in the family Vespidae, in the subfamily Eumeninae. Eumenids are solitary nest building wasps that stock their nests with many individuals of some species of leaf-eating arthropod prey (like caterpillars). There are many species of Ancistrocerus in North America.


Ancistrocerus waldenii are medium-sized black and yellow wasps that are about 10mm long. One of the best ways to distinguish A. waldenii from other species is by the deeply emarginate clypeus of the male wasps. Some key differences to look for are: a light spot between the eye and where the antenna starts, markings on the front of the head that are usually not close together and rarely join in the middle, with small markings underneath if they are present; the top part of the antenna is all black; a marking at the end of the fifth segment of its body, which may be missing in some wasps from the west; and a spot in the middle at the end of its sixth body segment, which is usually there but not in one of the other wasp species. The markings on A. waldenii range from bright yellow to creamy white.

Nest Structure

Ancistrocerus waldenii are solitary nesters, each female builds her own nests. They typically use mud or agglutinated sand to build their nest cells and nest plugs. Frequently, plugs have a smooth outer surface. A. waldenii stock their nests with paralyzed prey, as is typical of solitary nesting wasps. Prey choices include caterpillars, beetle and moth larvae, including leaf mining beetles and moths and garden or crop pests. Specifically, A. waldenii has been shown to prey upon leaf roller moth larvae in the family Tortricidae. Many of the arthropods that A. waldenii preys upon can be detrimental to food and ornamental crops. As such, they can be helpful to gardeners. In the wild, A. waldenii are known to build their nests in rock crevices or even the mortar between bricks in house walls.

Hole Sizes

No information at this time.


In Minnesota, Ancistrocerus waldenii can possibly be bivoltine, as each individual can produce up to two generations per year.

Activity Period

Ancistrocerus waldenii are most active in Minnesota from June to August but has been spotted as early as April and as late as September.


Buck, M., Marshall, S. A., & Cheung, D. K. B. 2008. Ancistrocerus waldenii. Identification Atlas of the Vespidae (Hymenoptera, Aculeata) of the northeastern Nearctic region. Retrieved from Coville, R. E. 1983. A note on the biology of Ancistrocerus waldenii flavidulus Bequaert (Hymenoptera: Eumenidae). Pan-Pacific Entomologist 58(3): 259.

Minnesota Record Map

These data are from the Minnesota Bee Atlas project.

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