From time to time we spot this rather unusual looking fly sitting in a sunny position somewhere in the Garden.
According to most online sources the adults, both male and female are likely to simply be looking for nectar to feed on. Here seen in May 2021 feeding at a Herb Robert…
…and later that same day visiting a Green Alkenet flower. Whether they act as pollinators themselves is unclear, but accidental pollination is likely to occur from time to time.
However as the English name suggests, there is another aspect to the life cycle of this species, which belongs to the family Conopidae. Although we have not witnessed this ourselves, the female of this species will quickly take a firm grip on a passing bumblebee (it seems the species isn’t that important) and using specialised apparatus located on its abdomen, proceed to inject an egg into the body of the bee before letting it go.
The larvae then develop and eventually pupate within the bee, resulting in the bee’s death.
There are several species of Conopidae represented in Great Britain, most are wasp mimics and often resemble hoverflies, which according to some sources are a closely related family.
So as long as we are providing both adult food by way of nectar and attracting larval food in the form of bombus species, then we will likely continue to record these guys, and hopefully other Conopidae in the future.