Click here to see an image of a RATTAILED MAGGOT

The larvae of the Syrphid flies are known as rattailed maggots. These maggots live in highly polluted water such as livestock lagoons, abandoned fish pools, foul pools and streams associated with barnyards. Rattailed maggots are able to live in the pools if sufficient solid food is available. The adult flies resemble honey bees in appearance and are often seen "hovering" near the ground in the barnyard vicinity. The adult flies do not bite or sting humans, and are considered beneficial because they are predaceous on aphids.

Source: http://ohioline.osu.edu