These hairy, bumbling flies are aptly named, and are often observed hovering and feeding around flowers. Some species possess a slender proboscis with which to reach deep into floral nectaries, but other remarkable variations exist as well. For example, the strikingly elongate Systropus macer is a convincing mimic of Ammophila wasps both in terms of morphology and behaviour. Bombyliid larvae develop as parasitoids of other insects.