Ancistrocerus catskill

Taxonomy 

Ancistrocerus catskill 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. Specifically, A. catskill has been shown to prey upon leafroller moth larvae in the families Oecophoridae, Pterophoridae, Pyralidae, Tortricidae and Gelechiidae (though these observations may be outdated and therefore need to be revised). Many of the arthropods that A. catskill preys upon can be detrimental to food and ornamental crops. As such, they can be helpful to gardeners. There are many species of Ancistrocerus in North America.

Description

Ancistrocerus catskill are medium-sized black and yellow wasps that are about 5.5-10mm long. Their bodies can be yellow to ivory in color, with different markings on their heads and bodies. The farther north this species is found, the more likely their markings are going to appear as ivory/creamy yellow rather than egg yolk yellow. One of the ways to tell this species from other species of Ancistrocerus is the presence of a light marking within the eye margins of male wasps. Otherwise, it is sometimes difficult to identify A. catskill from other species as both male and female wasps have many variations in the presence and size of markings on their bodies.

Nest Structure 

Ancistrocerus catskill 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. catskill 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. In the wild, A. catskill are known to build their nests in existing holes in wood and sticks, in old mud-dauber nests and empty burrows of ground-nesting bees.

Hole Sizes

No information at this time 

Voltinism

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

Activity

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

References 

Buck, M., Marshall, S. A., & Cheung, D. K. B. 2008. Ancistrocerus catskill. Canadian Journal of Arthropod Identification. Retrieved from https://cjai.biologicalsurvey.ca/bmc_05/06a_catskill.html