Hey, what is that insect on the sunflower leaf?
The one amongst all those aphids.
Look at those stripy back legs!
This is a parasitic wasp, or more technically a parasitoid wasp. Parasitoid wasps lay their eggs in other insects. The wasp larvae feed and complete their life cycle inside their host.
I think this wasp is rather large to have completed its development within an aphid, don't you? It is more likely to use something larger, such as caterpillars, as hosts.
After a bit of research I found out it is Diplazon laetatorius, a parasite of hover flies. Why is it hanging around aphids?
The larvae of hover or flower flies feed on aphids (see this previous post). So, this parasitoid of hover flies is sitting in the food of its host. Talk about sly!
Have you ever seen parasitoid wasps on plants?