Hellbender
Cryptobranchus alleganiensis
Crayfish, fish, tadpoles, insects, smaller salamanders including their own young
Pollution
The frills along its body
Hellbender salamander, lasagna lizard, Allegheny alligator, mud dog, mud devil, devil dog, water dog, leverian water newt, snot otter
Clean, cold freshwater streams
Hellbender
Appalachian Mountains from New York to Alabama
Hellbender
12 to 30 inches
Large fish, larger conspecifics, humans