This little wasp with remarkably hairy eyes, large stigma and long antennae, a new garden species, was clearly looking for something on the Butterfly bush branch hosting small colonies of Stigmus, Spilomena en Passaloecus digger wasps. Expert Paul Hoekstra pointed me to Dendrocerus, and using the Fergusson’s key ^{[Fergusson 1980]} it appears to be D. aphidum ^{[Soortenregister]}.

Dendrocerus is a parasitic group idiobiont hyper-ectoparasitoids on parasitoids of aphids (APHIDIDAE) that they find in aphid mummies ^{[Mackauer & Chow 2016]}. Both Passaloecus as well as Stigmus use aphids for their brood. Caught parasitised aphids can develop into a mummy within the digger wasp nest, so maybe she was looking for those; although she has not been observed entering a digger wasp nest.

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