THE XERCES SOCIETY FOR INVERTEBRATE CONSERVATION

Aquatic Invertebrates in Pacific Northwest Freshwater Wetlands
An Identification Guide and Educational Resource

Noteridae are closely related to predaceous water beetles (Dytiscidae), and adults of the two families may be mistaken for one another. Adult burrowing water beetles have streamlined oval bodies and modified back legs with swimming hairs. In adult Noteridae, the tibia of the front leg is extended into a large projecting hook; this structure is not present in adult Dytisicidae. In addition, a scutellum is never visible, as it is in some Dytiscidae.

The larvae have elongate, smooth sclerotized bodies that are generally broad and taper to a narrow tip; the legs are very thick and short. There are no gills, lobes, or filaments on the abdomenal segments. . The larvae obtain oxygen by coming to the water surface or tapping into plant tissues with the tip of their abdomen and using the plant's intercellular gases. Their common name is based on a genus from Eurasia and doesn't apply to our native taxa, which are mostly climbers as larvae and swimmers as adults.