These mating hoverflies were perfectly still, allowing me to focus accurately on them.
Note that the lower hoverfly, presumably the female, is not using her wings. Amazing that one set of wings can support the two individuals.
Many of these tiny "split-horn" sawflies flitting around my vegetable garden. Common Purslane (Portulaca oleracea) is a weed in my vege garden which may be attracting them. I believe the larvae feed in the inside of the purslane leaves. I think only the males have the split/bifid antennae, so the photos would be of a male. (The photos may not all be of the one individual).