It’s time for an interruption for Gasteruption!
That’s the genus of this wasp. Gasteruption. What a crazy name, right? This time of year, they’re somewhat easy to find. The common name for this thin, delicate insect is Carrot Wasp, because it likes to feed on flowers in the carrot family, like Queen Anne’s lace, aka wild carrot.
Teasing apart the bizarre scientific name, “gaster” is Latin for stomach (think of gastronomy, etc), and describes the long abdomen, ballooned at the end. I’ve not found a satisfactory reason for the “-uption” part of the name, but you can see a link below for one unlikely explanation. I wonder if Pierre Latreille (who coined it) was having a bit of fun.
To accompany the odd name, Carrot Wasps have a distinctive, odd look. They have swollen back tibias, a stretched-out neck, and the abdomen connects to the thorax in an unusual spot, a bit closer to the head than on a typical wasp.
These are gentle, pollinating creatures as adults. If you see one with something that looks like a stinger, you should know that this is an ovipositor, or egg-layer. It won’t be used for stinging.
As juveniles, Gasteruption are not so well behaved. Females lay their eggs in the nests of solitary bees (mostly) and wasps (sometimes). There, the Carrot Wasp larvae consume the other larvae in the nest, using the other young insects as their infant formula.
I’ve seen at least two species of these wasps at Mount Pisgah, although I’ve only seen the one with the longer ovipositor once, on the July Insect Walk (apologies for the poor image quality). Next time you’re out, keep your eyes on the wild carrots, and see if you can find a wild Carrot Wasp!
See more of Karen’s work here.
Academic paper on Gasteruption host species: https://academic.oup.com/zoolinnean/article/189/4/1105/5802323. Accessed 7/20/23.
Article from England with an iffy explanation of the name: https://www.gwct.org.uk/wildlife/species-of-the-month/2017/gasteruption-jaculator/. Accessed 7/20/23.
BugLady with a more likely etymology: https://uwm.edu/field-station/carrot-wasp/. Accessed 7/20/23.