An immature form of a fly of Eristalis or Helophilus spp. that can infest a necrotic wound or carcass. SYN: Eristalis sp.

The rat-tailed maggot is the larval form of certain species of hoverflies, which are insects that belong to the family Syrphidae. The larvae of these flies are called rat-tailed maggots because they have a distinctive, elongated “tail” that resembles a rat’s tail. The tail is actually a breathing tube that allows the maggot to obtain oxygen while it feeds in aquatic environments.

Rat-tailed maggots are typically found in stagnant or polluted water, such as sewage or manure pits. They are often used in bioassays to monitor the pollution levels of water bodies, as their presence in a particular habitat can indicate the presence of organic matter and pollutants in the water.

Despite their unappealing appearance, rat-tailed maggots play an important ecological role by consuming decaying organic matter in aquatic environments, which helps to break down and recycle nutrients. In addition, they are an important food source for many aquatic animals, such as fish and amphibians.

Overall, rat-tailed maggots are a unique and fascinating species that play an important ecological role in aquatic environments, and are useful indicators of water quality and pollution levels.