“Predacious Diving Beetles”
Family Overview
Dytiscidae
Predacious Diving Beetles
This is the largest North American family of aquatic beetles, including over 400 species in about 35 genera. Both adults and larvae can be found in almost any aquatic habitat, even in brackish water; however, they are most often found in lentic freshwater systems. The larvae tend to be climbers on rooted plants and swimmers; adults are swimmers and divers. Both larvae and adults are engulfing predators of small invertebrates and fish, and are sometimes cannibalistic. Some larvae have a channel along the inner margin of each mandible to help them ingest fluids from their prey. Their bite is quite painful. Despite living in the water, adults and larvae of most species must regularly resurface for air.
Characteristics
POLLUTION TOLERANCE
Mid-Atlantic: up to 5
Midwest: 4.1 - 7.9
Southeast: 1.8 - 10
0 = least tolerant, 10 = most tolerant
FEEDING HABITS
Engulfer / Predator
MOVEMENT
Diver
Swimmer
Swimmer
Diagnostic Characters
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