At first glance, a rat-tailed maggot can look like something from a horror movie. Its pale, plump body and extremely long “tail” make it easy to mistake for a parasite, but it is actually the larval stage of a hoverfly, commonly the drone fly.
That unusual tail is really a breathing tube called a siphon. The larva lives in stagnant, low-oxygen water containing decaying organic material and extends the tube to the surface like a snorkel while feeding underwater.
Rat-tailed maggots are generally harmless to people and pets. Finding one indoors usually does not indicate an infestation. They may accidentally enter from clogged drains, rain barrels, gutters, compost areas, or other places where standing water has collected.
Eventually, the larva leaves the water and moves to a dry location to pupate. It later emerges as an adult hoverfly, an insect that resembles a bee and visits flowers for nectar and pollen.
If you discover one indoors, simply remove it and check nearby drains or areas of standing water. Cleaning clogged drains and eliminating stagnant water can help prevent another appearance.
Despite their unsettling appearance, these strange larvae are simply another fascinating example of how unusual nature can sometimes look.
