Dytiscidae

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Common Name Predaceous Diving Beetle
Phylum Arthropoda
Class Insecta
Order Coleoptera
Family Dytiscidae
Description 3-25mm but range from 1-40mm. Their middle and hind legs are flattened and have dense hairs. Laterally, the body curves outwards on the top and bottom. They have non-clubbed antennae and a pair of finger-like structures that project forward from their mouth and are usually visible only ventrally. For more photos, refer to our online gallery: tinyurl.com/urmy5zf
Habitat Primarily lentic-littoral but also lotic-depositional. They can be found in every type of aquatic habitat, but most commonly along the margins of ponds and slow streams. They can also be found in temporary puddles, ditches, and brackish waters.
Feeding Information Voracious predators. Larvae catch their prey with sickle-shaped jaws and inject fluid that dissolves the prey's insides. Adult Dytiscidae have chewing mouthparts and will consume anything they can catch and subdue, including larger vertebrates such as tadpoles and fish.
Water Quality Tolerance Mostly facultative, some are somewhat sensitive.
References Voshell & Wright. 2002.