Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. They are a paraphyletic group encompassing all tetrapods excluding the amniotes, and all extant amphibians belong to the subclass Lissamphibia. Evolved to be mostly semiaquatic, amphibians have adapted to inhabit a wide variety of habitats, with most species living in freshwater, wetland or terrestrial ecosystems. Their life cycle typically starts out as aquatic larvae with gills known as tadpoles, but some species have developed behavioural adaptations to bypass this.
Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All ten extant salamander families are grouped together under the order Urodela from the group Caudata. Salamander diversity is highest in eastern North America, especially in the Appalachian Mountains; most species are found in the Holarctic realm, with some species present in the Neotropical realm.
Ambystomatidae is a family of salamanders belonging to the order Caudata in the class Amphibia. It contains two genera, Ambystoma and Dicamptodon. Ambystoma contains 32 species and are distributed widely across North America, while Dicamptodon contains four species restricted to the Pacific Northwest. These salamanders are mostly terrestrial and eat invertebrates, although some species are known to eat smaller salamanders. They can be found throughout the US and some areas of Canada in damp forests or plains. This family contains some of the largest terrestrial salamanders in the world, the tiger salamander and the coastal giant salamander. Some species are toxic and can secrete poison from their bodies as protection against predators or infraspecific competition. Neoteny has been observed in several species in Ambystomatidae, and some of them like the axolotl live all of their lives under water in their larval stage.
The Pacific giant salamanders are members of the genus Dicamptodon. They are large salamanders endemic to the Pacific Northwest in North America. They are included in the family Ambystomatidae, or alternatively, in their own monogeneric family Dicamptodontidae.
The California tiger salamander is a vulnerable amphibian native to California. It is a mole salamander. Previously considered to be a subspecies of the tiger salamander, the California tiger salamander was recently designated a separate species again. The California tiger salamander distinct population segment (DPS) in Sonoma County and the Santa Barbara County DPS are listed as federally endangered, while the Central California DPS is listed as federally threatened. The Sonoma County, south San Joaquin, and the Santa Barbara County DPS have diverged from the rest of the California tiger salamander populations for over one million years, since the Pleistocene and they may warrant status as separate species.
The long-toed salamander is a mole salamander in the family Ambystomatidae. This species, typically 4.1–8.9 cm (1.6–3.5 in) long when mature, is characterized by its mottled black, brown, and yellow pigmentation, and its long outer fourth toe on the hind limbs. Analysis of fossil records, genetics, and biogeography suggest A. macrodactylum and A. laterale are descended from a common ancestor that gained access to the western Cordillera with the loss of the mid-continental seaway toward the Paleocene.
The four-toed salamander is a lungless salamander native to eastern North America. It is the only species of the monotypic genus Hemidactylium.
The Ezo salamander, also known as the Hokkaido salamander, Noboribetsu salamander, or Ezo Sanshouo in Japanese is a species of salamander in the family Hynobiidae. Prior to 1923 the species was also classified by the binomial scientific name Satobius retardatus. H. retardatus is endemic to Japan's northernmost prefecture, the island of Hokkaido. The species is a pond-type salamander, and its natural habitats are temperate forests, temperate shrubland, swamps, freshwater marshes, intermittent freshwater marshes, freshwater springs, irrigated land, canals, and ditches.
Desmognathus fuscus is a species of amphibian in the family Plethodontidae. The species is commonly called the dusky salamander or northern dusky salamander to distinguish it from populations in the southern United States which form several distinct species, the southern dusky salamanders. The northern dusky salamander is the most widespread representative of its genus in Canada. It can be found in eastern North America from extreme eastern Canada in New Brunswick south to South Carolina. The size of the species' total population is unknown, but is assumed to easily exceed 100,000. The species' habitat differs somewhat geographically; dusky salamanders in the northern part of the range prefer rocky woodland streams, seepages, and springs, while those in the south favor floodplains, sloughs, and muddy places along upland streams. They are most common where water is running or trickling. They hide under various objects, such as leaves or rocks, either in or near water. Alternatively, they may enter burrows for protection. The dusky salamander lays its eggs close to water under moss or rocks, in logs, or in stream-bank cavities. The larval stage which follows is normally aquatic.
The ocoee salamander is a species of salamander in the family Plethodontidae. This salamander has a variety of colors and patterns, and got its name from Tennessee state wildflower. Its natural habitats are temperate forests, rivers, intermittent rivers, freshwater springs and wet rocks in mountainous areas of the Southeastern United States. It was first described by Nicholls in 1949. They are territorial and feed on small invertebrates. It is widely distributed in the southeastern United States and is listed as "Least Concern" by the International Union for Conservation of Nature.
The blackbelly salamander is a species of salamander in the family Plethodontidae. It is endemic to the United States. Its natural habitats are rivers, intermittent rivers, and freshwater springs. It is threatened by habitat loss.
The Blue Ridge two-lined salamander is a species of salamander in the family Plethodontidae, endemic to the United States. This species is found in the southern Appalachian Mountains, mostly south of Virginia. To the north is a similar salamander, Eurycea bislineata, or the northern two-lined salamander. Its genus, Eurycea contains 33 species and includes taxa that have either a metamorphic life cycle or larval-form paedomorphosis. In species that metamorphose, there can be within-and among-population variation in larval life-history characteristics, e.g., duration of the larval period and size at metamorphosis. Intraspecific geographic variation in species of Eurycea has been attributed to several factors: temperature, stream order and productivity of the larval habitat.
The red salamander is a species of salamander in the family Plethodontidae endemic to the eastern United States. Its skin is orange/red with random black spots. Its habitats are temperate forests, small creeks, ponds, forests, temperate shrubland, rivers, intermittent rivers, freshwater, trees springs. Overall this species is common and widespread, but locally it has declined because of habitat loss and it is considered threatened in Indiana. Red salamanders eat insects, earthworms, spiders, small crustaceans, snails, and smaller salamanders. To eat, they extend their tongue to capture prey on the tip of it and retract it back into their mouths. The red salamander, as a member of the family Plethodontidae, lacks lungs and respires through its skin.
Cope's giant salamander is a species of salamander in the family Dicamptodontidae, the Pacific giant salamanders. It is native to Washington and Oregon in the Pacific Northwest region of the United States.
The California giant salamander is a species of salamander in the family Ambystomatidae. Dicamptodon ensatus is endemic to California, in the western United States. The species once additionally included individuals now belonging to the species D. aterrimus and D. tenebrosus, under the common name Pacific giant salamander, which now refers to the genus and family.
The coastal giant salamander is a species of salamander in the family Dicamptodontidae. It is endemic to the Pacific Northwest of North America. There are three closely related species to this taxon: D. ensatus, D. copei, and D. aterrimus.
