(ssp pictured: Ozark Hellbender - C. alleganiensis bishopi)
A North American species of giant salamander (family Cryptobranchidae) and is the third largest salamander in the world - reaching up to 74cm (28in) with an adult weighing anywhere from 3.5-5.5lb. They are found in rivers and streams in the northeastern US, with C.a. bishopi found primarily in the rivers of the Ozark plateau.
Recently (especially the Ozark subspecies) has shown a decline in populations. It has been proposed to be added to the list of endangered species (see http://www.fws.gov/midwest/endangered/amphibians/ozhe/index.html).
These giant salamanders have a very unique ecological niche that requires their specific habitat to remain undisturbed. They require a special balance of dissolved oxygen and temperature of fast moving water to survive and breed successfully, limiting them to specific ponds and streams with the proper requirements. What does that mean? It means that if this species goes extinct, most other organisms that rely on them within that ecological niche will also go extinct.
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