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Species guide - species detail

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Chrysura pacifica or kyrae (Cuckoo wasp)



Chrysura is a genus of cuckoo wasps in the family Chrysididae. Chrysura pacifica and Chrysura kyrae are very similar, and we have not distinguished between these species.


Chrysura pacifica and Chrysura kyrae are bright green-blue iridescent wasps. These species are closely related and have strong morphological similarities. DNA analysis may be required in order to confidently determine the difference between them. There are no teeth at the end of their last abdominal segment, and the area located below the three ocelli and between the two compound eyes is smooth and lacks features.

Nest Structure

Chrysura pacifica is one of the most abundant cuckoo wasp species in North America. Chrysura kyrae is less common, but can also be found in Minnesota. Cuckoo wasps are known to be nest parasites (kleptoparasites) of various hymenoptera species. Since cuckoo wasps do not make nests or provide food provisions for their young, they rely on their hosts to provide that for them instead. During nest provisioning, the cells of the host’s nest are open and vulnerable to parasitism. The Chrysura wasp takes advantage of this opportunity and will enter the host’s nest (once the host has left). The female Chrysura will then lay their egg inside the host’s cell alongside the host’s egg. The host will then return to the nest. Unaware of the intruder, the host will seal up the cell encasing the host and cuckoo wasp egg. The Chrysura larva will then consume the young megachilid host. In most cases, this leads to the death of the host and the successful emergence of the cuckoo wasp. The known hosts for Chrysura pacifica and Chrysura kyrae are species of megachilid bees (Megachile, Osmia, etc). In order to confidently determine host associations for Minnesota Bee Atlas specimens, we will need to separate these two Chrysura species through DNA analysis. Osmia lignaria, Osmia tersula, and Osmia albiventris are all possible hosts for either Chrysura pacifica or Chrysura kyrae in the MN Bee Atlas project.

Hole Sizes

No information at this time.


No information at this time.

Activity Period

No information at this time.


No information at this time.

Minnesota Record Map

These data are from the Minnesota Bee Atlas project.

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