Riffle Beetles

Benthic Macroinvertebrates

Sensitive Benthos

Moderately Tolerant Benthos

Pollution Tolerant Benthos

Riffle beetle larvae

Metamorphosis:

complete (see our life cycle page for more information)

Larvae:

resemble small "torpedoes" with circular stripes or rings around body; pointed at both ends with a "fuzzy" mass at one end; color usually grayish; length less than 1/2 inch.

Reproduction:

females deposit eggs on plant materials under water.

Adults:

unique in that they are also aquatic and are found more often than the larvae; adults are beetle-like, tiny, and usually black.

Food:

primarily plant material such as diatoms and algae.

Scientific Name:

Class: Insecta
Order: Coleoptera
Family: Elmidae

Indicator Role:

found in fast-moving waters, indicates ample oxygen supply

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.

Riffle beetle larvae and adults