Common Mudpuppy
Encyclopedia
The Mudpuppy is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of salamander that is part of the genus, Necturus. They live an entirely aquatic lifestyle in the eastern part of North America in lakes, rivers, and ponds. Mudpuppies go through paedomorphosis and retain their external gills. Because skin and lung respiration alone is not sufficient for gas exchange, mudpuppies must rely on external gills as their primary means of gas exchange. Mudpuppies are usually a rusty brown color and can grow to an average length of 33 cm (13 inches). Mudpuppies are nocturnal creatures and only come out during the day if the water they live in is murky. Their diet consists of almost anything they can get in their mouths and includes insects, earthworms, mollusks, and annelids. Once a female mudpuppy reaches sexual maturity, at six years of age, she can lay an average of 60 eggs. In the wild, the average life span of a mudpuppy is 11 years. Because of their prevalence and larger size than other salamanders, mudpuppies are good organisms for dissections.

Appearance

Mudpuppies can be a rusty brown color with gray and black and usually have blackish blue spots, however some albino adults have been reported in Arkansas. In clear, light water their skin gets darker, likewise in darker water their skin gets lighter in color. At sexual maturity mudpuppies can be 20 cm (8 inches) long and continue to grow to an average length of 33 cm (13 inches), though specimens up to 43.5 cm (17 inches) have been reported. They have external gills
External gills
External gills are the gills of an animal, most typically an amphibian, that are exposed to the environment, rather than set inside the pharynx and covered by gill slits, as they are in most fishes. Instead, the respiratory organs are set on a frill of stalks protruding from the sides of an animals...

 that 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. The distal portion of the gills are very filamentous and contain many capillaries. Mudpuppies also have small flattened limbs that can be used for slowly walking on the bottoms of streams or ponds, or they can be flattened against the body during short swimming spurts. They have mucus glands which provide a slimy protective coating, and granular glands that secrete poison that is used as defense against predators.

Distribution

Necturus
Necturus
Necturus is a genus of aquatic salamander only found in the eastern United States. They are commonly known as Waterdogs and Mudpuppies...

, which includes mudpuppies, live in streams, lakes, and ponds in the eastern part of North America. They appear in the southern section of Canada, go as far south as Georgia, and range from the midwest of the United States to North Carolina. In the more northern section they are called mudpuppies, and in the southern portion they are called waterdogs. The mudpuppy hides under cover such as rocks and logs during the day and becomes more active at night. However, in muddy waters, the mudpuppy may become active during the day and not just at night. Mudpuppies can even live under the ice when lakes freeze.

Diet

Mudpuppies have two rows of teeth that they use to eat their prey. At both sides of their mouths their lips interlock which allows them to use suction feeding. They are carnivorous creatures and will eat almost anything they can get in their mouths. Typically they prey upon things such as insects, mollusks, annelids, small fish, amphibians, earthworms, and spiders. The mudpuppy has few predators but may include fish, crayfish
Crayfish
Crayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related...

, turtles, and water snakes. Because fisherman frequently catch and discard them, humans are considered to be one of their main predators.

Reproduction

Mudpuppies take six years to reach sexual maturity. Mating typically takes place in autumn, though eggs are not laid till much later. When males are ready to breed, their cloaca
Cloaca
In zoological anatomy, a cloaca is the posterior opening that serves as the only such opening for the intestinal, reproductive, and urinary tracts of certain animal species...

s become swollen. Males deposit their spermatophores in the substratum of the environment. The female will then pick them up with her cloaca and store them in a small specialized gland, a spermatheca
Spermatheca
The spermatheca , also called receptaculum seminis , is an organ of the female reproductive tract in insects, some molluscs, oligochaeta worms and certain other invertebrates and vertebrates...

, until the eggs are fertilized. Females store the sperm until ovulation and internal fertilization take place, usually just prior to deposition in the spring. Before the eggs are deposited, male mudpuppies leave the nest. Once ready, the female will deposit the eggs in a safe location, usually on the underside of a rock or log. They can lay anywhere from 20–190 eggs, usually an average of 60. The eggs are pigmentless and approximately 5–6 mm in diameter. The mother will stay with her eggs during the incubation period (approximately 40 days). Hatchlings are about 2.5 cm and grow to 3.6 cm before the yolk is completely consumed. After six years of maturing, the mudpuppies are able to repeat this reproduction cycle.

See also

  • Axolotl
    Axolotl
    The axolotl , Ambystoma mexicanum, is a neotenic salamander, closely related to the Tiger Salamander. Larvae of this species fail to undergo metamorphosis, so the adults remain aquatic and gilled. It is also called ajolote...

  • Mudpuppy (Necturus maculosus), Natural Resources Canada
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK