The Bee flies consist of several hundred genera and over 4,500 species worldwide, and there are 9 resident species in the UK.
These insects resemble a furry bee with a long proboscis. The adults can be seen hovering before flowers and using their proboscis to feed on nectar and pollen. The larvae are parasitoids of solitary bee and beetle eggs and larvae. Eggs are deposited near to suitable nesting burrows of the host bees. After hatching the larvae crawls into the burrows in search of a host larvae cell, it then becomes inactive until the host larvae is nearly fully grown, at which point the bee-fly larvae attaches itself to the host larvae as an ectoparasitoid.