The common mudpuppy (Necturus maculosus) is a species of salamander in the family Proteidae. It lives an entirely aquatic lifestyle in parts of North America in lakes, rivers, and ponds. It goes through paedomorphosis and retains its external gills. Because skin and lung respiration alone is not sufficient for gas exchange, the common mudpuppy must rely on external gills as its primary means of gas exchange. It is usually a rusty brown color and can grow to an average total length (including tail) of 13 in (330 mm). It is a nocturnal creature, and is active during the day only if the water in which it lives is murky. Its diet consists of almost anything it can get into its mouth, including insects, mollusks, and earthworms (as well as other annelids). Once a female common mudpuppy reaches sexual maturity at six years of age, she can lay an average of 60 eggs. In the wild, the average lifespan of a common mudpuppy is 11 years.

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