Pacific giant salamanders Temporal range: Paleocene to recent, | |
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Dicamptodon tenebrosus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Amphibia |
Order: | Urodela |
Family: | Ambystomatidae |
Genus: | Dicamptodon Strauch, 1870 |
Synonyms [1] | |
ChondrotusCope, 1887 |
The Pacific giant salamanders are members of the genus Dicamptodon. They are large salamanders endemic to the Pacific Northwest in North America. [1] [2] [3] They are included in the family Ambystomatidae, [1] [4] [5] or alternatively, in their own monogeneric family Dicamptodontidae. [2] [3]
Pacific giant salamanders are defined by their wide protruding eyes, costal grooves, thick arms, and dark background coloring. Dicamptodon have a snout-vent-length (SVL) of 350 mm, a broad head, laterally flexible flattened tails, paired premaxillae that are separate from the nasals, and the aquatic larvae have gills. Dicamptodon have lacrimals and pterygoids that are present, but quadratojugal are absent. [3]
While most salamanders are silent, the Pacific giant salamander is one of several salamanders that have vocal abilities. When startled, these salamanders may respond with a croaky-sounding cry similar to that of a barking dog.
Pacific giant salamanders are semi-aquatic animals [6] that occupy both aquatic and terrestrial habitats. They are commonly found in various lotic environments in altitudes ranging from 0 to 7000 feet above sea level in the Pacific Northwest and Northern California. Aquatic salamander abundance has been shown to increase with increasing rock coverage, and decrease with increasing water velocity, and tend to prefer cold mountain streams and lakes. [7] Pacific giant salamanders also utilize terrestrial refuge sites such as decaying wood, burrows, or under rocks. [8]
The genus Dicamptodon was formerly thought to contain two species, Cope's giant salamander (D. copei) on the Olympic Peninsula, Washington, and the Pacific giant salamander (D. ensatus) which consisted of three geographic populations, an Idaho isolate, a group in northern California, and a group in Oregon and Washington. [9] In 1989, genetic studies showed D. copei to be a distinct species, and the D. ensatus populations to consist of three species: the Idaho giant salamander (D. aterrimus) in Idaho, and two highly divergent species with a narrow hybrid zone in California, the coastal giant salamander (D. tenebrosus) (ranging from northern California to Washington), and the California giant salamander (D. ensatus) (limited only from Santa Cruz County to Mendocino County in California). [10] The earliest known member of this genus and family is D. antiquus from the Paleocene of Alberta. [11]
There are four extant Dicamptodon species. [1] [2]
Image | Scientific name | Common Name | Distribution |
---|---|---|---|
Dicamptodon aterrimus | Idaho giant salamander | forested watersheds from lake Coeur d’Alene to the Salmon River, and in two locations in Montana around Mineral County, Idaho | |
Dicamptodon copei | Cope's giant salamander | Olympic Peninsula to northern Oregon | |
Dicamptodon ensatus | California giant salamander | Northern California | |
Dicamptodon tenebrosus | Coastal giant salamander | Northern California, Oregon, Washington, and southern British Columbia. | |
The Cryptobranchidae are a family of fully aquatic salamanders commonly known as the giant salamanders. They include the largest living amphibians. The family is native to China, Japan, and the eastern United States. They constitute one of two living families—the other being the Asiatic salamanders belonging to the family Hynobiidae—within the Cryptobranchoidea, one of two main divisions of living salamanders.
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 torrent salamanders or Cascade salamanders are a family of salamanders (Rhyacotritonidae) with only one genus, Rhyacotriton. The torrent salamanders are endemic to the United States in the Pacific Northwest.
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 genus Taricha consists of four species of highly toxic newts in the family Salamandridae. Their common name is Pacific newts, sometimes also western newts or roughskin newts. The four species within this genus are the California newt, the rough-skinned newt, the red-bellied newt, and the sierra newt, all of which are found on the Pacific coastal region from southern Alaska to southern California, with one species possibly ranging into northern Baja California, Mexico.
Necturus is a genus of aquatic salamanders in the family Proteidae. Species of the genus are 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 – as an amphibian with gill slits, it is often dissected in comparative anatomy classes. The common mudpuppy has the largest distribution of any fully aquatic salamander in North America.
The speckledblack salamander, previously known as just the black salamander, is a species of salamander in the family Plethodontidae. It is endemic to the U.S. state of California. Its natural habitats are temperate forests and temperate grassland. It is threatened by habitat loss.
The Idaho giant salamander is a species of salamander. There are three closely related species to this taxon: D. ensatus,, D. copei and D. tenebrosus also known as the.
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 southern torrent salamander is a member of the salamander family Rhyacotritonidae. This species of torrent salamander is found the farthest south in the Pacific Northwest region. It is a small salamander endemic to the region from Northern California to Northern Oregon. It is one of four species of Rhyacotriton, along with R. cascadae, R. kezeri and R. olympicus. All species of Rhyacotriton are small, with their body lengths being less than 5 inches. The species reproduces annually, with an extended courtship and egg-laying period. The time it takes from oviposition to reach sexual maturity ranges from five to eight years, making the generation interval rather long. The larval stage, from hatching to metamorphosis, lasts 2.0-2.5 yr, with females requiring another 1.5–2.0 yr until they can first breed. They reach sexual maturity 1.0-1.5 yr after metamorphosis which occurs between 4.5 and 5.0 yr. This species feeds on small insects and spiders. Although it is found over a large area, it is not a migratory creature. It is preyed on by Pacific giant salamanders and garter snakes.
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.
There are 14 species of amphibians and 5 species of reptiles known to occur in Mount Rainier National Park.