Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broad sense, it is paraphyletic group encompassing all tetrapods excluding the amniotes. 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. Their life cycle typically starts out as aquatic larvae with gills known as tadpoles, but some species have developed behavioural adaptations to bypass this.
A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura. The oldest fossil "proto-frog" Triadobatrachus is known from the Early Triassic of Madagascar, but molecular clock dating suggests their split from other amphibians may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforest. Frogs account for around 88% of extant amphibian species. They are also one of the five most diverse vertebrate orders. Warty frog species tend to be called toads, but the distinction between frogs and toads is informal, not from taxonomy or evolutionary history.
A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found in adult amphibians such as a lateral line, gills and swimming tails. As they undergo metamorphosis, they start to develop functional lungs for breathing air, and the diet of tadpoles changes drastically.
The Alytidae are a family of primitive frogs. Their common name is painted frogs or midwife toads. Most are endemic to Europe, but three species occur in northwest Africa, and a species formerly thought to be extinct is found in Israel.
The common toad, European toad, or in Anglophone parts of Europe, simply the toad, is a frog found throughout most of Europe, in the western part of North Asia, and in a small portion of Northwest Africa. It is one of a group of closely related animals that are descended from a common ancestral line of toads and which form a species complex. The toad is an inconspicuous animal as it usually lies hidden during the day. It becomes active at dusk and spends the night hunting for the invertebrates on which it feeds. It moves with a slow, ungainly walk or short jumps, and has greyish-brown skin covered with wart-like lumps.
The common frog or grass frog, also known as the European common frog, European common brown frog, European grass frog, European Holarctic true frog, European pond frog or European brown frog, is a semi-aquatic amphibian of the family Ranidae, found throughout much of Europe as far north as Scandinavia and as far east as the Urals, except for most of the Iberian Peninsula, southern Italy, and the southern Balkans. The farthest west it can be found is Ireland. It is also found in Asia, and eastward to Japan. The nominative, and most common, subspecies Rana temporaria temporaria is a largely terrestrial frog native to Europe. It is distributed throughout northern Europe and can be found in Ireland, the Isle of Lewis and as far east as Japan.
Midwife toads are a genus (Alytes) of frogs in the family Alytidae, and are found in most of Europe and northwestern Africa. Characteristic of these toad-like frogs is their parental care; the males carry a string of fertilised eggs on their backs, hence the name "midwife". The female expels a strand of eggs, which the male fertilizes externally. He then wraps them around his legs to protect them from predators in the water. When they are ready to hatch, the male wades into shallow water, where he allows the tadpoles to leap out of their eggs. Five separate species of midwife toads are found across western Europe, northern Africa, and Majorca.
The American toad is a common species of toad found throughout Canada and the eastern United States. It is divided into three subspecies: the eastern American toad, the dwarf American toad and the rare Hudson Bay toad. Recent taxonomic treatments place this species in the genus Anaxyrus instead of Bufo.
The southern toad is a true toad native to the southeastern United States, from eastern Louisiana and southeastern Virginia south to Florida. It often lives in areas with sandy soils. It is nocturnal and spends the day in a burrow. Its coloring is usually brown but can be red, gray, or black. It is approximately 8 cm (3 inches) long.
The Majorcan midwife toad is a frog in the family Alytidae. It is endemic to the Balearic Island of Majorca in the Mediterranean Sea. An example of Lazarus taxon, the species was first described from fossil remains in 1977, but living animals were discovered in 1979.
The Yosemite toad is a species of true toad in the family Bufonidae. Endemic to the Sierra Nevada of California, the species ranges from the Alpine County to Fresno County. Yosemite toads are only found in the montane to subalpine elevational zone of 1,950–3,445 m (6,398–11,302 ft) asl. The Yosemite toad is similar to the nearby western toad, but in many ways adapted to a high elevation lifestyle. It was initially described during the Grinnell Survey of California, by an undergraduate student of Joseph Grinnell named Charles Camp.
The Arizona toad is a species of toad in the family Bufonidae. It is endemic to the south-western United States, where its natural habitats are temperate lowland forests, rivers and streams, swamps, freshwater marshes, freshwater springs, ponds, open excavations, irrigated land, and seasonally flooded agricultural land.
The Iberian midwife toad or brown midwife toad, in Portuguese sapo-parteiro-ibérico, is a species of frog in the family Alytidae found in Portugal and western Spain. It is typically found in open habitats such as meadows and open oak forests. Habitat loss is one of the threats to its survival.
The Betic midwife toad or Sapo Partero Bético is a species of frog in the family Alytidae. It is endemic to mountainous in south eastern Spain. Its natural habitats are temperate forests, freshwater marshes, intermittent freshwater marshes, pastureland, ponds, and aquaculture ponds. It is threatened by habitat loss.
Alytes maurus is a species of frog in the family Alytidae . It is endemic to Morocco. Its natural habitats are temperate forests, Mediterranean-type shrubby vegetation, rivers, freshwater marshes, freshwater springs, rocky areas, and rural gardens. Phenomena such as habitat fragmentation, water pollution, climate change, and the introduction of chytrid fungus into ecosystems all pose threats to the well-being of these organisms.
The Iberian painted frog is a species of frog in the family Alytidae. It is found in Portugal and Spain, where its natural habitats are temperate forests, temperate shrubland, Mediterranean-type shrubby vegetation, rivers, intermittent rivers, swamps, freshwater marshes, intermittent freshwater marshes, sandy shores, arable land, and grassland. It is threatened by habitat loss.
Discoglossus pictus, the Mediterranean painted frog or simply painted frog, is a species of frog in the family Alytidae.
Bufotes, the Eurasian green toads or Palearctic green toads, is a genus of true toads. They are native to Europe, western and central Asia and northern Africa; a region roughly equalling the western and central Palearctic. Historically they were included in the genus Bufo and then for a few years placed in Pseudepidalea, which is a synonym of the currently accepted name Bufotes.
