• 22 species in North America


Identification Tips:

• Huge; up to 75 mm (!)
• Wide, flattened, oval shaped body
• Narrow head with protruding eyes
• Large front legs, tipped with claw, held in front of body
• Veins visible in tips of wings
• Middle and hind legs fringed with hairs (for swimming)
• Pair of retractable appendages at end of abdomen

Life History:

• Found in still or slow moving water with abundant vegetation, or plant debris
• Often at surface,positioned head down breathing through appendages at tip of abdomen
• Able do dive for long periods breathing air trapped under wings
• Voracious predators; kill and consume invertebrates, tadpoles and small fish
• Prey is grabbed with front legs and mixture of poison and digestive juice is injected via the mouth beak
• Prey is digested inside its own skin and solution sucked out
• Strong fliers
• One generation per year
• Adults overwinter buried in mud

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.