|Wikispecies has information related to: Amphizoa|
Amphizoa is a genus of beetles, placed in its own family, Amphizoidae. It comprises six species, three from western North America and three from China. The vernacular name "trout-stream beetle" comes from the original finding of A. insolens and A. lecontei in high mountain streams, although other species occur at lower elevation. They are notable as a possible intermediate stage between terrestrial and aquatic beetles; while living in the water, they are not good swimmers and physically resemble ground beetles more than other types of water beetle.
The larvae also live underwater, but breathe through the eighth abdominal segment and must therefore stay close to the surface. They cling to rocks or floating debris. Both adults and larvae are predators, but will also scavenge dead insects.
- T. Keith Philips and Weiping Xie, "Amphizoidae", in Ross H. Arnett, Jr. and Michael C. Thomas, American Beetles (CRC Press, 2001), vol. 1