I have to admit when I heard this species common name, I knew it had to be included as my third and final species in the "Salamanders & Newts" base set. Doing a "lives under underwater" species is always a little bit of a challenge to make the render interesting and believable, but I think I did a reasonable job here. For its environment, I used a rocky ultrascenery creek. The Common Mudpuppy is a species of salamander that lives an entirely aquatic lifestyle in parts of the Great Lakes region and surrounding states in lakes, rivers, and ponds, in North America. Adult mudpuppies can be 8 to 13 inches (20-33 cm) long. They are usually a rusty brown color with gray and black and often has blackish-blue spots. In clear, light water, their skin gets darker, likewise in darker water, their skin gets lighter in color. Their external gills resemble ostrich plumes and their size depends on the oxygen levels present in the water. In stagnant water, mudpuppies have larger gills, whereas in running streams where oxygen is more prevalent, they have smaller gills. Typically they prey upon animals such as insects and their larvae, mollusks, annelids, crayfish, small fish, amphibians, earthworms, and spiders. Mudpuppies are generally docile and rarely bite humans, but they do possess mild toxins in their skin secretions, acting as a defense mechanism against potential predators.