Necturus

Meet the waterdog.

These animals live in water. They live in Canada and the United States. They like clear water with rocks.

Waterdogs have red gills on their necks. They use these to breathe. They do not have eyelids. They also have a wide tail.

They like to stay in cold water. They hide under rocks or logs. At night, they hunt for food. They like to eat crayfish.

These creatures are very interesting to see.

Meet the waterdogs. Some people call them mudpuppies. These animals are a type of salamander. They live in water in Canada and the United States.

Waterdogs have a special way of growing. They are paedomorphic. This means the adults still look like babies. They keep their red gills to breathe. They also have no eyelids. They have two pairs of short limbs. They also have a wide tail.

The common mudpuppy is a well-known species. It can grow quite large. It is often brown or gray. It may have dark spots on its back.

These animals like clear water with rocks. They like cold water, too. They are most active when it is cool. During the day, they hide under logs or rocks. At night, they hunt for food. They like to eat crayfish. They may also eat fish in the winter.

Females lay eggs under rocks in the spring. They stay to guard the nest. They may even eat their eggs if they need power.

The Necturus are a special group of water salamanders. Many people call them waterdogs or mudpuppies. These animals live in the water in Canada and the eastern United States.

One famous type is the common mudpuppy. It lives in many places like lakes and rivers. Scientists often study them in classes to learn about how bodies work. They are very important for knowing if a river is healthy.

These salamanders have a unique way of growing. They are paedomorphic, which means the adults still look like babies. They keep their bushy red gills to help them breathe underwater. They also have two pairs of gill slits and no eyelids. Their bodies are sturdy with two pairs of short limbs. They also have a large tail that is flattened on the sides. Even though they have small lungs, they mostly live in the water.

Scientists have spent a long time naming these species. Viosca described the Alabama waterdog in 1937. He also worked on the Red River mudpuppy in 1938. Other researchers like Brimley named the Neuse River waterdog in 1924. In 1991, a scientist named Collins suggested a new name for one type. He thought the Red River mudpuppy should be its own species. However, most people did not follow that idea.

There are seven or eight different species in this group. The common mudpuppy is the largest and lives in many areas. It can be brown or gray with dark spots. It may even have spots on its belly too.

Other types live in specific places like Alabama or Texas. For example, the dwarf waterdog lives from Virginia to Georgia. Some old fossils of these animals have even been found. One was found in Saskatchewan and another in Florida.

Living in the water requires a specific way of life. These animals like clear water with rocks and no mud. They like it when the water is cool. They are most active between 9.1 and 20.2 degrees Celsius. During the day, they hide under logs or rocks. At night, they come out to hunt for food. They love to eat crayfish and sometimes fish. In the spring, females lay eggs under rocks and guard them.

The genus *Necturus* consists of a group of aquatic salamanders. These animals belong to the family Proteidae. They are native to the eastern United States and Canada.

Many people call them waterdogs or mudpuppies. The most famous member is the common mudpuppy, or *Necturus maculosus*. This species has the largest distribution of any fully aquatic salamander in North America. Because they have visible gill slits, they are often used in comparative anatomy classes.

Scientists study them to understand how different animal bodies are built.

These salamanders are unique because they are paedomorphic. This means the adults keep physical features that look like larval or baby stages. For example, they retain external gills to breathe underwater. They also have two pairs of gill slits and lack eyelids.

Their bodies are moderately robust with two pairs of short limbs. They also possess a large, laterally compressed tail that helps them move. While they do have lungs, these organs are quite small.

This combination of traits allows them to live their entire lives in the water.

There are currently seven or eight recognized species within the genus. The common mudpuppy, *N. maculosus*, lives from the southern section of Canada down to Georgia.

Other species have much smaller ranges. The Alabama waterdog, *N. alabamensis*, is found in Alabama. The Neuse River waterdog, *N. lewisi*, lives in North Carolina.

The dwarf waterdog, *N. punctatus*, ranges from southeastern Virginia to southcentral Georgia. Other species include the western waterdog, *N. beyeri*, and the Apalachicola waterdog, *N. moleri*. There is also the Escambia waterdog, *N. mounti*. Some species, like the Red River mudpuppy, are currently considered subspecies of the common mudpuppy.

Taxonomy, or the science of naming and classifying organisms, is still being debated for *Necturus*. Herpetologists are still studying the exact relationships between these species. In 1991, a researcher named Collins suggested that the Red River mudpuppy should be its own species, *N. louisianensis*. However, most scientists did not follow this recommendation. A 2018 study identified two different lineages: the Great Lakes lineage and the Mississippi River lineage. Even so, the study did not conclude if these should be called separate species or subspecies.

The Society for the Study of Reptiles and Amphibians currently views the Red River mudpuppy as a subspecies.

Life for a mudpuppy follows specific seasonal patterns. Females lay their eggs under rocks or large objects in late spring or early summer. The females stay to guard the nests until the eggs hatch. While guarding, they must forage for food. If they cannot find enough food, they may eat some of their own eggs to get energy.

The larvae are believed to stay protected under rocks as late as November. This careful guarding helps ensure the next generation survives in their watery homes.

These animals prefer specific environments to thrive. They live in surface waters that are clear and have rocky bottoms without much silt. *N. maculosus* can be found in lakes, rivers, streams, and creeks. They prefer shallow waters that stay cool. They are most active when temperatures are between 9.1 and 20.2 degrees Celsius. During the day, they hide under logs, rocks, or plant debris. At night, they come out to forage. They prefer to eat crayfish, but they will also eat fish during the winter and spring.

*Necturus* species are very important for understanding the health of an ecosystem. Because they are sensitive to their environment, they act as indicators of water quality. However, they face several modern threats. They have been harmed by chemical pollutants and siltation, which is when fine mud covers the rocky bottom. They can also be caught by accident during passive ice fishing, which is known as bycatch.

Additionally, a fungus called chytrid (Bd) has affected mudpuppies in captivity, though scientists do not yet know if it affects them in the wild. Protecting their clear, rocky habitats is essential for their survival.