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Species guide - species detail

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Kocourekia debilis (Tiny parasitic wasps)



Kocourekia debilis is a tiny parasitic wasp in the family Eulophidae, believed to be most closely related to Melittobia spp. There is only one Kocourekia species known in North America, Kocourekia debilis, and three known species in the world. They were uncommon in Bee Atlas blocks, but we had a few nests that were parasitized by them each year. We believe that this is the first time K. debilis has been recorded in Minnesota or the upper Midwest region.


Kocourekia debilis are tiny dark brown wasps that emerge in groups from host nests. Kocourekia look like Melittobia, and are distinguished by dense hairs on the head and numerous scattered hairs on the scutellum. K. debilis are entirely dark brown, except for brownish-yellow tarsomeres (lower part of the legs). Male Kocourekia have not been described for any of the three known species.

Nest Structure

Kokourekia debilis hosts are largely unknown, but are thought to include small sphecid wasps. In Bee Atlas blocks, they emerged from column 3 holes with resin plugs, which would have been made by either small crabronid wasps or Heriades spp. bees (resin bees). Unfortunately, no hosts emerged from the nests, so we were not able to identify the hosts with certainty. From our limited data, it seems like Kocourekia debilis has a relatively specialized host/parasite relationship in comparison with Melittobia, which are generalist parasites of bees and wasps.

Hole Sizes

Kokourekia debilis emerged from column 3 (1/8 - 3/16") holes in Bee Atlas blocks. Each Kocourekia "specimen" includes many individuals which emerged as a group from the nest.


No information at this time.

Activity Period

No information at this time.


Cao, H. et al. 2017. Notes on Kocourekia Bouček (Hymenoptera: Eulophidae: Tetrastichinae) with description of a new species from China. Zootaxa 4317(2): 391-400. Gibson, G.A.P., J.T. Huber, and J.B. Woolley, eds. 1997. Annotated Keys to the Genera of Nearctic Chalcidoidea (Hymenoptera). NRC Research Press. Ottowa, Ontario, Canada. LaSalle, J. 1994. North American genera of Tetrastichinae (Hymenoptera: Eulophidae). Journal of Natural History 28(1): 109-236. Thank you to John Luhmen for help identifying parasitic wasps

Minnesota Record Map

These data are from the Minnesota Bee Atlas project.

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