Today my wife and editor found this creature crawling on the inside of the patio door while moving her house plants outside. Like the trained naturalist she is, she captured it in a bug box and delivered it to me. Here is her story.
"My plants were in a sorry shape. Some of them had scale insects and mealybugs. Sweet sticky juice was on the floor under them. Just the sort of thing other insects might love. I'm used to seeing spiders but this was a flying insect with a thread waist. Having no bug box with me, but very curious about what it was, I pinched it between my thumb and pointer finger until I could find a box. I was surprised that it had very hard body."
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| Barb's wasp |
Measuring 11mm, I didn't expect to have much luck identifying it beyond a wasp. Inaturalist suggested it was an aphid wasp in the tribe Psenini. These are typically black wasps characterized by an exceedingly slender petiole connecting the thorax and abdomen. In frontal views it had a square silvery pattern that looked like the grill on a Rolls Royce.
Searching for Psenini in Bugguide I came up with photographs of a
Pseneo sp. with the identical facial features. This was closer to an identification that I had dared to hope for. Marci Hess has this photograph on Bugguide which shows it much better. It appears to be frowning, probably from the bright light. Her photograph below has a much better view of the slender petiole.
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| Barb's wasp |
Aphid wasps are members of the subfamily
Pemphredoninae. They capture aphids and take them back to their nest cells. There they will lay paralyzed, waiting for the wasp larva to emerge and consume it, staying fresh without refrigeration. In another wasp family, the
Aphidius sp. lays a single egg in an aphid. Its venom stuns the aphid's ovaries, saving its energy for the emerging wasp larva.
Quite a story from catching a little insect on the glass. I married the right woman.
