A Pellucid Hoverfly

This is the striking, and relatively common hoverfly, Volucella pellucens. Yesterday afternoon I watched this female feeding on dogwood blossom. It is a very large fly, mostly black, with a translucent, pale first abdominal segment. Males are very obvious this time of year, as they hover, a few meters high, near trees. Even in flight, their colour pattern and size makes them easy to identify. They live in woodland and park glades, although I have also seen it a few times in my garden.
The adults feed on umbellifers, buddleia and bramble flowers, amongst others. An interesting aspect of this hoverfly life cycle, although still relatively poorly known, is that its larvae are found inside the nests of social bees and wasps. Adult hoverflies are apparently able to enter unnoticed the well guarded nests, and lay their eggs in the nest. The larvae feed at the bottom of the nest, scavenging on dead adult bees or wasps or grubs, pollen and dropped food and other debris. In the autumn, when the nest is vacated, the larvae might move into the combs, when they finish off any late grubs.

More information
Stubbs, A. E., & Falk, S. J. (1983). British hoverflies. An illustrated identification guide. British Entomological and Natural History Society.