''Necturus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of aquatic salamanders native to the eastern United States and Canada. They are commonly known as waterdogs and mudpuppies. The common mudpuppy ''(N. maculosus)'' is probably the best-known

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

– as an amphibian with gill slits, it is often dissected in comparative anatomy classes.

Taxonomy

The genus is under scrutiny by

herpetologists Herpetology (from Greek ἑρπετόν ''herpetón'', meaning " reptile" or "creeping animal") is the branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts, and caecilians (gymnophiona)) an ...

. The relationship between the species is still being studied. In 1991 Collins elevated ''N. maculosus louisianensis'' to full species status, usually considered a subspecies of the common mudpuppy (''N. maculosus''), but his interpretation was not largely followed.Petranka, J.W. (1998). Salamanders of the United States and Canada. Smithsonian Institution Press . However, a 2018 study confirmed it as a distinct species, with

Amphibian Species of the World ''Amphibian Species of the World 6.1: An Online Reference'' (ASW) is a herpetology database. It lists the names of frogs, salamanders and other amphibians, which scientists first described each species and what year, and the animal's known range. ...

following these results, although other authorities do not.''''

Species

There are seven to eight species: Two known fossil species, '' N. krausei'' and an unnamed species, are respectively known from the

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pala ...

of Saskatchewan and from Florida during the Pleistocene.

Description

''Necturus'' are paedomorphic: adults retain larval-like morphology with external gills, two pairs of gill slits, and no eyelids. They are moderately robust and have two pairs of short but well-developed limbs and a large, laterally compressed tail. Lungs are present but small. Typical adult size is in total length, but ''Necturus punctatus'' is larger and may reach .

Ecology

''Necturus'' occur in surface waters, preferentially with clear water and rocky substrates without silt. They forage during the night and eat a variety of prey, but have preference for crayfish.

References

External links

* {{Taxonbar, from=Q641652 Proteidae Amphibian genera Extant Paleocene first appearances Taxa named by Constantine Samuel Rafinesque