Necturus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of aquatic salamander

Salamander

Salamander is a common name of approximately 500 species of amphibians. They are typically characterized by a superficially lizard-like appearance, with their slender bodies, short noses, and long tails. All known fossils and extinct species fall under the order Caudata, while sometimes the extant...

 only found in the eastern United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. They are commonly known as Waterdogs and Mudpuppies. The Common Mudpuppy

Common Mudpuppy

The Mudpuppy is a species 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...

 (Necturus maculosus) is likely the most well known 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...

 in this group.

Species

• Common Mudpuppy
  Common Mudpuppy
  The Mudpuppy is a species 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...
  
   (Necturus maculosus) (Rafinesque
  Constantine Samuel Rafinesque-Schmaltz
  Constantine Samuel Rafinesque-Schmaltz, as he is known in Europe, was a nineteenth-century polymath who made notable contributions to botany, zoology, the study of prehistoric earthworks in North America and Mesoamerican ancient linguistics.Rafinesque was eccentric, and is often portrayed as an...
  
  , 1818)
  • Red River Mudpuppy
    Red River Mudpuppy
    The Red River mudpuppy , also called Louisiana waterdog, is a subspecies of mudpuppy. Some herpetologists consider this salamander to be a full species .-Geographic range:...
    
     (Necturus maculosus louisianensis) Viosca, 1938
• Alabama (Black Warrior) Waterdog (Necturus alabamensis) Viosca, 1937
• Gulf Coast Waterdog (Necturus beyeri) Viosca, 1937
• Neuse River Waterdog (Necturus lewisi) Brimley, 1924
• Dwarf Waterdog
  Dwarf Waterdog
  The Dwarf Waterdog is the smallest member of the family Proteidae, and is endemic to the United States.-Description:...
  
   (Necturus punctatus) (Gibbes, 1850)

Taxonomy

The genus Necturus is under scrutiny by herpetologists

Herpetology

Herpetology is the branch of zoology concerned with the study of amphibians and reptiles...

. The relationship between the species is still being studied, and more changes are sure to come. Most recently, the Red River Mudpuppy (N. louisianensis) was elevated to full species status, after being considered only a subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

of the Common Mudpuppy (N. maculosus). However, not all herpetologists agree on this change.