Bee flies might be mistaken for large, fuzzy mosquitoes because of the long stinger-like mouthpart (its called proboscis) but there are for sipping nectar, not blood. Most bee fly species such as our large bee fly (Bombylius major) are covered in long hairs. Other species have silvery scales that wear off rapidly as the insect ages. Many species have dark ornament patterns on their wings.
These flies are very good at hovering which helps to reinforce their resemblance to bees. They may be seen out and about from April through to June. They forage on a range of flowers such as lilac and plum blossoms.
The eggs are flicked by the adult female toward the entrance of the underground nests of solitary bees and wasps. After hatching, the larvae find their way into the nests to feed on the other larvae.
Here a video that shows a large bee fly hovering and flying from flower to flower: