• 1 genus and 24 species in North America


Identification Tips:

• Body length 10-25 mm
• 7 pair of stout, flexible, segmented, pointed filaments protrude from abdominal segments
• Single long tapering filament fringed with fine hairs extends from tip of abdomen like a tail
• Sturdy, toothed jaws at front of head
• Head and thorax (segments with legs) are hardened, but abdomen is soft

Life History:

• Burrowers that occur in all types and sizes of freshwater habitats
• Rarely found in flowing water, in rivers they will be limited to pools or eddies
• Most are found in areas soft bottom where there is a lot of organic matter, but some species live in sand
• Predatory on smaller invertebrates

Flying insects
Females lay eggs on undersides of leaves or twigs overhanging water

Very SensitiveSomewhat SensitiveFacultativeSomewhat TolerantVery Tolerant

Primary Information Source:
Voshell, J. Reese. 2002. A Guide to Common Freshwater Invertebrates of North America. McDonald and Woodward Publishing Company. Blacksburg, Virginia.