Alderflies

Benthic Macroinvertebrates

Sensitive Benthos

Moderately Tolerant Benthos

Pollution Tolerant Benthos

Alderfly larvae

Metamorphosis:

complete (see our life cycle page for more information)

Larvae:

possess a single tail filament with distinct hairs; body is thick-skinned with 6 to 8 filaments on each side of the abdomen; gills are located near the base of each filament; color brownish.

Reproduction:

female deposits eggs on vegetation that overhangs water, larvae hatch and fall directly into water.

Adults:

dark with long wings folded back over the body.

Food:

larvae are aggressive predators, feeding on other adult aquatic macroinvertebrates; as secondary consumers, they are eaten by other larger predators.

Scientific Name:

Class: Insecta
Order: Megaloptera
Family: Sialidae

Indicator Role:

Alderflies are generally intolerant of pollution.

Information Source:

McDonald, B., W. Borden, J. Lathrop.1990. Citizen Stream Monitoring: A Manual for Illinois. Illinois Department of Energy and Natural Resources, ILENR/RE-WR-90/18. Springfield, Illinois.

Alderfly larvae and adult