Most salamanders breed in water and are gregarious at breeding time, when there is usually a courtship display. In most species fertilization is internal. The male deposits sperm packets, which the female picks up with the cloaca; the sperm is then stored until fertilization takes place. The eggs, surrounded by gelatinous material, are usually laid in ponds or brooks, where they develop into aquatic larvae that can breathe by means of gills. A few salamanders breed on land, laying their eggs under rotting vegetation; the young pass through the gilled stage in the egg, emerging as miniature adults. Such strictly terrestrial forms are the red-backed salamander (Plethodon cinereus) and slimy salamander (P. glutinosus) of E United States and the slender salamander (Batrachoseps attenuatus) of the Pacific coast.
Most salamanders, including most that remain in an aquatic environment, go through a typical amphibian metamorphosis into air-breathing adults. Generally the adults have lungs, but in the large family of lungless salamanders (Plethodontidae) breathing occurs entirely through the skin and the lining of the throat. In a few salamanders growth occurs without metamorphosis, and the gilled, juvenile form is able to reproduce. This phenomenon (called neoteny) is found in the sirens (family Sirenidae) of S United States and N Mexico, in the mud puppies (family Protidae), and in the Mexican axolotl. It may also occur in the Western varieties of the North American tiger salamander (Ambystoma tigrinum) under certain environmental conditions. The newts are a large, widely distributed family of salamanders; North American species include the red-spotted newt, which goes through a terrestrial stage known as the red eft.
The North American blind salamanders (several genera in the family Plethodontidae) live in underground streams, caves, and wells in S United States. As adults they have whitish, translucent skin, which covers their eyes. The olm is a European blind salamander related to the mud puppy. The giant salamander (Dicamptodon ensatus) of the NW United States grows to 12 in. (30 cm) in length. The hellbender (Cryptobranchus alleganiensis) of E United States and the so-called Congo eel (Amphiuma means) are large aquatic species. The former, of the same family as the Japanese giant salamander, grows to 20 in. (50 cm); the latter, slender and eellike in appearance, with tiny legs, may reach 30 in. (75 cm).
There are over 200 salamander species, classified in approximately 60 genera and 8 families of the phylum Chordata, subphylum Vertebrata, class Amphibia, order Urodela.
Salamander (Salamandra terrestris)
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Salamander (orig. from Persian: sām, "fire", and andarūn, "within") is the common name for a group of approximately 500 species of amphibians. Typically characterized by slender bodies, short noses, and long tails. All known fossil and extant species comprise the order Caudata, while sometimes extant are distinctly called Urodela. Salamanders have four front toes and their hind legs have five. Their moist skin usually makes them reliant on habitats in or near water, or under some protection (e.g., moist ground), often in a wetland. Some salamander species are fully aquatic throughout life, some take to the water intermittently, and some are entirely terrestrial as adults. All species lay eggs in water. Uniquely among vertebrates, they are capable of regenerating lost limbs, as well as other body parts.
Respiration differs among the different species of salamanders. In those that lack lungs, respiration is done through gills as water passes over the gill slits. Some salamanders that are terrestrial have lungs that are used in respiration similar to that in mammals. However, some terrestrial species lack both lungs and gills and perform gas exchange through their skin, a process known as valarian respiration in which the capillary beds are spread throughout the epidermis, including inside the mouth.
Hunting is yet another unique aspect of salamanders. Muscles surrounding the hyoid bone contract to create pressure and actually "shoot" the hyoid bone out of the mouth along with the tongue. The tip of the tongue is composed of a mucus which creates a sticky end to which the prey is captured. Muscles in the pelvic region are used in order to reel the tongue and the hyoid back to its original position. To find their prey, salamanders use trichromatic color vision in the ultraviolet range based on three photoreceptor types maximally sensitive around , 500 nm and 570 nm.
Caudates are found on all continents except for most of Africa, Australia and Antarctica. One-third of the known salamanders, are found in North America. The highest concentration of these is found in the Appalachian Mountains region. Species of salamander are numerous and found in most moist or arid habitats in the northern hemisphere. They usually live in or near brooks, creeks, ponds, and other moist locations.
|'''Cryptobranchoidea (Giant salamanders)|
|Family||Common Names||Example Species||Example Photo|
|Cryptobranchidae||Giant salamanders||Hellbender (Cryptobranchus alleganiensis)|
|Hynobiidae||Asiatic salamanders||Hida Salamander (Hynobius kimurae)|
|Salamandroidea (Advanced salamanders)|
|Ambystomatidae||Mole salamanders||Marbled Salamander (Ambystoma opacum)|
|Amphiumidae||Amphiumas or Congo eels||Two-toed Amphiuma (Amphiuma means)|
|Dicamptodontidae||Pacific giant salamanders||Pacific Giant Salamander (Dicamptodon tenebrosus)|
|Plethodontidae||Lungless salamanders||Red Back Salamander (Plethodon cinereus)|
|Proteidae||Mudpuppies and olms||Olm (Proteus anguinus)|
|Rhyacotritonidae||Torrent salamanders||Southern Torrent Salamander (Rhyacotriton variegatus)|
|Salamandridae||Newts and true salamanders||Alpine Newt (Triturus alpestris)|
|Sirenidae||Sirens||Greater Siren (Siren lacertina)|
Numerous legends have developed around the salamander over the centuries, many related to fire. This connection likely originates from the tendency of many salamanders to dwell inside rotting logs. When placed into a fire, the salamander would attempt to escape from the log, lending to the belief that salamanders were created from flames - a belief that gave the creature its name.
Associations of the salamander with fire appear in the Talmud and the Hadith, as well as in the writings of Conrad Lycosthenes, Benvenuto Cellini, Ray Bradbury, David Weber, Paracelsus and Leonardo da Vinci.