Portal:Amphibians

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The Amphibian Portal

Anaschisma

Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all tetrapods, excluding the amniotes (tetrapods with an amniotic membrane, such as modern reptiles, birds, and mammals). All extant (living) amphibians belong to the monophyletic subclass Lissamphibia, with three living orders: Anura (frogs), Urodela (salamanders), and Gymnophiona (caecilians). 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 (such as riparian woodland, fossorial and even arboreal habitats). Their life cycle typically starts out as aquatic larvae with gills known as tadpoles, but some species have developed behavioural adaptations to bypass this.

The young generally undergo metamorphosis from larva with gills to an adult air-breathing form with lungs. Amphibians use their skin as a secondary respiratory surface and some small terrestrial salamanders and frogs lack lungs and rely entirely on their skin. They are superficially similar to reptiles like lizards, but unlike reptiles and other amniotes, require water bodies in which to breed. With their complex reproductive needs and permeable skins, amphibians are often ecological indicators; in recent decades there has been a dramatic decline in amphibian populations for many species around the globe.

The earliest amphibians evolved in the Devonian period from sarcopterygian fish with lungs and bony-limbed fins, features that were helpful in adapting to dry land. They diversified and became ecologically dominant during the Carboniferous and Permian periods, but were later displaced in terrestrial environments by early reptiles and basal synapsids (mammal predecessors). The origin of modern amphibians belonging to Lissamphibia, which first appeared during the Early Triassic, around 250 million years ago, has long been contentious. However the emerging consensus is that they likely originated from temnospondyls, the most diverse group of prehistoric amphibians, during the Permian period. (Full article...)

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Selected frog article

European tree frog Hyla arborea

Hylidae is a wide-ranging family of frogs commonly referred to as "tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semiaquatic. (Full article...)

List of selected frog articles

Selected salamander article

The greater siren (Siren lacertina) is an amphibian and one of the three members of the genus Siren. The largest of the sirens and one of the largest amphibians in North America, the greater siren resides in the coastal plains of the southeastern United States. (Full article...)

List of selected salamander articles
Caudata Ambystomatidae Cryptobranchoidea Salamanders in folklore Salamandroidea Sexual selection in amphibians Sirenidae Urodela

Did you know? – show different entries

...that the Cheat Mountain salamander of West Virginia is the only vertebrate known to be unique to that state?
... that the Permian amphibian Trimerorhachis either brooded young in its mouth or ate them?
... that the Cumberland Dusky Salamander is believed to hybridize with the Ocoee Salamander?
... that female European cave salamanders do not normally eat while they guard their eggs for six months or more?
... that in hot weather, the eastern spadefoot toad (pictured) may aestivate in the deep burrow it has dug?

Selected amphibian type

European fire-bellied toad (Bombina bombina), a member of the family Bombinatoridae

Toad is a common name for certain frogs, especially of the family Bufonidae, that are characterized by dry, leathery skin, short legs, and large bumps covering the parotoid glands.

A distinction between frogs and toads is not made in scientific taxonomy, but is common in popular culture (folk taxonomy), in which toads are associated with drier, rougher skin and more terrestrial habitats. (Full article...)

List of selected amphibian type articles
Frog Salamander Caecilian

Selected images

Image 1
White-lipped tree frog
Photo: JJ Harrison
The white-lipped tree frog (Litoria infrafrenata) is the world's largest tree frog. This species is native to the rainforests of Northern Queensland, New Guinea, the Bismarck Islands and the Admiralty Islands. It can reach a length of over 13 cm (5 in), with females growing larger than males. The lower lip has a distinctive white stripe, giving this species its common name.
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Image 2
Phantasmal poison frog
Photograph: H. Krisp
The phantasmal poison frog (Epipedobates tricolor) is a species of poison dart frog endemic to Ecuador. First described by George Albert Boulenger in 1899, this endangered species is found only in rainforests on the slopes of the Andes.
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Image 3
Common toads in amplexus
Photo: Bernie Kohl
Two common toads (Bufo bufo) in amplexus, a form of pseudocopulation found in amphibians and limulids. A male common toad grasps a female with his front legs as part of the mating process. Common toads stay in amplexus for several days. As the female lays a long, double string of small black eggs, the male fertilises them with his sperm; the gelatinous egg strings, which may contain 3000 to 6000 eggs and be 3 to 4.5 metres (10 to 15 ft) in length, are later tangled in plant stalks.
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Image 4
Eastern Banjo Frog
Photo credit: Fir0002
The Eastern Banjo Frog (Limnodynastes dumerilli) is native to eastern Australia and has been introduced to New Zealand. The frog is also commonly called the pobblebonk after its distinctive "bonk" call, which is likened to a banjo string being plucked. Adults are roughly seven to eight cm long.
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Image 5
Blue Mountains Tree Frog
Photo: Benjamint444
The Blue Mountains Tree Frog (Litoria citropa) is a moderate-sized species of tree frog, up to about 60 mm (2.4 in) in length. It is native to coastal and highland areas of eastern Australia, especially in the Blue Mountains, hence its name.
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Image 6
New England Tree Frog
Photo credit: LiquidGhoul
The New England Tree Frog (Litoria subglandulosa) is a species of frog native to the streams of the New England Tablelands, New South Wales, Australia.
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Image 7
Iberian midwife toad
Photograph: Benny Trapp
The Iberian midwife toad (Alytes cisternasii) is a species of frog in the family Alytidae found in Portugal and western Spain. Its natural habitats are temperate forests and shrubland, Mediterranean-type shrubby vegetation, intermittent rivers and freshwater marshes, pastureland, and aquaculture ponds. The species is affected by habitat loss, and the IUCN lists it as being "Near Threatened".
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Image 8
Dendropsophus microcephalus
Photo: Brian Gratwicke
A male Dendropsophus microcephalus frog, displaying its vocal sac—membranes of skin under the throat or on the corner of the mouth that distend to amplify its call. The species lives in moist areas in most of Central America and northern South America.
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Image 9
Marsh frog
Photo: Marie-Lan Nguyen
The marsh frog (Pelophylax ridibundus) is a species of true frog and the largest frog native to Europe; females of this sexually dimorphic species may be up to 17 centimetres (6.7 in) long. The marsh frog feeds mainly on insects, but it also eats smaller amphibians, fish, and rodents.
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Image 10
Epirus water frog
Photograph: Benny Trapp
The Epirus water frog (Pelophylax epeiroticus) is a species of frog in the family Ranidae. It is found in western Greece, including Corfu, and the southern areas of Albania. The species is collected from the wild for human consumption.
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Image 11
Common frog
Photo: Richard Bartz
The common frog (Rana temporaria) is found throughout much of Europe. Adults have a body length of 6 to 9 cm (2.4 to 3.5 in) and vary in colour, with the ability to lighten and darken their skin to match their surroundings. They will feed on any invertebrate of a suitable size and, apart from the breeding season, live solitary lives.
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Image 12
Marsh frog
Photograph credit: Charles James Sharp
The marsh frog (Pelophylax ridibundus) is a species of amphibian native to Europe and parts of Asia. It is the largest type of frog in most of its range, growing to a snout-to-vent length of around 100 mm (4 in); tadpoles can reach up to 190 mm (7.5 in) in length, but this usually occurs in places with long winters where the tadpole has time to grow. Marsh frogs hibernate during the winter, either underwater or in burrows, and are able to use the Earth's magnetic field to locate breeding ponds. This marsh frog was photographed in Kampinos National Park, Poland.
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Image 13
Southern brown tree frog
Photograph: JJ Harrison
The southern brown tree frog (Litoria ewingii) is a species of tree frog native to Australia found in a wide range of habitats. Reaching 45 millimetres (1.8 in), this species is generally brown, but green and green-striped morphs are also recorded.
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Image 14
Atelopus limosus
Photograph: Brian Gratwicke
A female limosa harlequin frog (Atelopus limosus) in Panama. This endangered species of toad in the family Bufonidae inhabits stream banks in tropical moist lowland forests and rivers of the Chagres watershed. It is found in two colour forms, one in lowlands and one in uplands.
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Image 15
Panamanian golden frog
Photograph: Brian Gratwicke
The Panamanian golden frog (Atelopus zeteki) is a rare species of toad endemic to Panama. First described by Emmett Reid Dunn in 1933, this species was found close to mountain streams on the eastern side of the Tabasará mountain range in Coclé and Panamá Provinces, but is now critically endangered and possibly extinct in the wild.
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Selected toad article

Frostius pernambucensis males

Frostius – known as Frost's toads – is a small genus of true toads consisting of only two species endemic to Brazil. The genus was proposed by David C. Cannatella in 1986 based on an analysis of a species previously classified as Atelopus. Various morphological and life-history information first suggested that it is sister taxon to Atelopus or Atelopus + Osornophryne, but later molecular evidence suggests that it is sister taxon to Oreophrynella. It was named for Darrel Frost in recognition of his work on anuran systematics. (Full article...)

List of selected toad articles

Selected caecilian article

Chikila fulleri, also known as the Kuttal caecilian, Fuller's caecilian, and Fuller's chikila, is a species of caecilian from South Asia. In 2012 it was reassigned to a newly erected family, Chikilidae. (Full article...)

List of selected caecilian articles