What are the Major Groups of Amphibian?

Amphibia is a kind of primitive, newly landed, five-toed type temperature-changing tetrapod with bare skin, numerous secretory glands and mixed blood circulation. The individual development cycle has a metamorphic process, that is, larvae living in the water with gills (new organs) breathing, complete metamorphosis in a short period of time, and become an adult living on the land with lung breathing energy. There are about 4,000 species of about 40 families and 400 genera in 3 orders. Except for Antarctica and marine islands, they are found all over the world. There are more than 270 species in 11 families and 40 genera in China, which are mostly distributed in the south of the Qinling Mountains, western China, and southwest mountainous areas. Amphibians have inherited from fish the characteristics suitable for aquatic life, such as the shape of eggs and larvae, and the way of spawning. They also have new characteristics that are suitable for terrestrial life, such as sensory devices, motor devices, and respiratory and circulatory systems. Metamorphosis is not only a new-born adaptation, but also reflects the change process of major organ systems from water to land ^[1] .

Amphibians have three different body shapes. They have weak defense, proliferation, and migration capabilities.

Except for oceans and deserts, they are found in a variety of habitats on the plains, hills, mountains and plateaus. Vertical distribution can reach 5000 meters. Some species are resistant to brackish water. In tropical and subtropical humid and hot regions, the species are the largest, and the species in the north-south temperate zone are decreasing, and only a few species can reach the southern edge of the Arctic Circle. There are aquatic, terrestrial, arboreal and burrowing. The heat-generating and heat-dissipating functions are not perfect enough. Generally, they are active in the hidden place from dusk to dawn, and spend the summer or hibernation in the hot or cold season. Ingest animal foods (mainly frogs scrape plant foods). Fish, snakes, birds, and beasts can all become their natural enemies.

history

As the first vertebrates to land, amphibians have the longest history of development, but have a history of the origin and evolution of amphibians.

The ancestors of the amphibians were meat fin fish, but

Amphibian

It is unclear exactly what type of meat fin fish originated. In the past, it was generally believed that the fanfish of the total finfish represented by the Devonian true palm fin Eusthenopteron was an ideal ancestor of amphibians, but recent studies have denied this claim, so the ancestors of amphibians were meat. Fan-bone fish, air-spinned fish, or lung fish in fin fish are yet to be discovered.

The earliest amphibians were the ichthys and echidnosaurus that appeared in the late Paleozoic Devonian, and they have more fish characteristics, such as retaining tail fins, and failing to adapt to life on land. Ichthyostomys and Echinochloids represent transition types between fish and amphibians, but recent research shows that they are only a side branch of the early evolution of amphibians, not ancestor types of other amphibians. The most primitive amphibians are still the most primitive. To be discovered. After entering the Carboniferous Period, amphibians rapidly differentiated, and reached the extreme in the last two periods of the Paleozoic Carboniferous and Permian. This era is therefore also called the amphibians era. Amphibians in this period are diverse and adapt to different living environments. Some are quite suitable for land life, and some return to the water. Some large species such as the Carboniferous Eogyrinus can grow to 4-8 meters in length, and their habits are quite modern. Crocodile, there are many strange looking species. Unlike amphibians, these early amphibians mostly had scale armor. After the end of the Paleozoic era, most primitive amphibians went extinct, only a few survived, and new types of amphibians began to appear.

Fish rock sturgeon and spiny rock sturgeon

Amphibian

The teeth have a labyrinth similar to that of the total finfish, and are classified in the class Amphidonia of the amphibians. Ichthyophyllum and Echinochloids form the genus Ichthyodes of the order Mithodontia. The order of the ichthyodons has been extended to the early Carboniferous since the late Devonian period. The project has also appeared. These two orders of the subgenus Myopia represent the main types of amphibians and the types of amphibians that have evolved toward reptiles. Lepidoptera is the main type of amphibians, spreading all over the world during the Carboniferous and Permian periods, and some members of the Lepidoptera still flourished for a period of time at the end of the Paleozoic. It is the only one of the primitive amphibians that continued into the Mesozoic. On behalf of them, some did not become extinct even in the late Mesozoic. These Mesozoic dentitions were widely distributed and huge in size. For example, the Triassic Mastodonsaurus had a skull length of more than one meter and lived mainly in water. The type that evolved toward reptiles is the Carboniferous order, which is mainly found in Europe and North America and has not been very prosperous. The most famous of the Carboniferous order is the Permian lizard Seymouria. The lizard has the characteristics of both amphibians and reptiles. Whether it was an amphibian or a reptile was disputed until it was discovered. It is confirmed that it is an amphibian. Because lizards lived later than the earliest reptiles, they cannot be the ancestors of reptiles, and the ancestors of reptiles have yet to be discovered. Another class of amphibians that are very similar to reptiles is the broad-toothed dragon Diadaectes. They were once placed in the reptilian cuposaurus and later found to be amphibians in the world.

In the Carboniferous and Permian

Amphibian

Ji also once survived a class of primitive amphibians with no lost teeth, which was classified as the subclass Acanthocephala. The shell vertebrae are relatively small and very specialized, including some strange-looking members, such as the Carboniferous Dolichosoma, which has no limbs at all, and the Permian hoe Diplocaulus has a unique triangular head. All crustaceans were extinct at the end of the Paleozoic, and it is unclear whether the offspring remained.

After entering the Mesozoic, modern types of amphibians began to appear. Modern amphibians have smooth bodies without scales, bare and moist skin, and are covered with mucus glands. This kind of skin can play a role in breathing, and some amphibians do not even have lungs and rely on the skin to breathe. The earliest slippery amphibians were Triassic proto-frogs, such as Triadobatrachus, which are somewhat similar to modern frogs, but have short tails. The order Oculata and Aniptera appear later. The Order Opilata appeared in the Jurassic period, and the Anapoda has a reliable record in the early Cenozoic. However, the Anapoda is more primitive and may have originated earlier. Shell vertebrae, some people think that the three have a lot in common, have a common origin.

Impeccable

There are 162 species of 34 genera in 6 families. It is widely distributed in tropical and subtropical regions between the equator and the North-South Tropic of Cancer on all continents. There are only 2 species in 1 family in China. The body is oblong, like an earthworm or snake, with bare skin, most ring-shaped wrinkles and mucus, without limbs and limb bands. Usually living in wetland camp caves, the eyes are degraded under the skin, and the ears have no eardrum. The olfactory organs are well developed. It has ribs but no sternum. The male body has an adaptor protruding from the cloaca wall at the end. In-vivo fertilization. Oviparous or viviparous. Eggs lay in burrows. The larvae go through a stage with 3 external gills before hatching. The external gills only have the function of absorbing nutrients. When the larvae hatched, the outer gills had disappeared and the larvae moved to water to complete development. The larvae have an outer gill cleft and a caudal fin, swim to the surface and breathe with the lungs (the right lung is developed). Finally, the gill fissure was closed, the caudal fin disappeared, and it moved to land to become an adult in a burrowing cave. It mainly eats insects, worms, and earthworms. ^[1]

Promidae

Rhinatrematids are distributed in the northern regions of South America. There are 9 genera in 2 genera. Ophiophylidae has the most primitive features, such as retaining the tail, opening the mouth in front of the head, a large number of skulls, relatively large eyes, synapses connected to the eyes, many scales and many small folds on the body's ring folds Wait. Oviparidae is ovum-like, with larvae having small outer gills, living in water, returning to the soil after metamorphosis into adults.

Frogidae

Ichthyophiids of the family Frogidae have 36 genera in 2 genera and are distributed in tropical Asia. Fish sturgeons are very similar to wormworms. Some people put them into the same family. Fish worms also have many original characteristics similar to wormworms, but the synapses are located in front of the eyes. They are slightly more advanced than wormworms. Frogidae are ovum-producing, and female maggots coil the eggs around the body until they hatch. In China, there are two types of sturgeon bream and banna fish bream. Among them, Banna fish bream was once considered to be two-band fish bream, and later it was confirmed as an independent species. They are the only representatives of the impefect order in China.

Brachionidae

Uraeoptyphlidae has 1 genera and 4 species, and its distribution is limited to India. Blind-tailed earthworms also have some primitive and progressive features. The original features include more scales, more skulls, and short tails. Progressive features include the mouth below the head, the synapses away from the eyes and the ring folds on the body. Folding and so on. Blind earthworms are oviparous, but the larval stage is short.

Wormworm

There are 2 genera and 5 species of Scolecomorphids in the family Verminidae, and these two genera are distributed in equatorial eastern and western Africa, respectively. Wormworms are progressive earthworms with mouths below the head, reduced skulls, and no scales and tails. The eyes of worms are usually covered by thin bones, but the eyes are exposed when the synapses are extended. Wormworms in East Africa are viviparous and have no aquatic larvae.

Eulogidae

There are 88 genera of 23 genera in the family Eucaeidae. They are distributed in tropical America, equatorial Africa, India, and the Seychelles Islands in the Indian Ocean. Eulogidae is a progressive earthworm with many progressive characteristics, but there are also a few species with some primitive characteristics. The members of the family Eulogidae have a variety of body types, habits, and life histories, ranging in size from small to large, with oviparous and viviparous births. The largest and smallest earthworms belong to the family Euceridae, and the largest earthworm Caecilia thomsoni in South America is more than one and a half meters long. The smallest short earthworm, Grandisonia brevis, is only 11 cm in length.

Brachidae

Typhlonectidae has 12 genera in 4 genera, distributed in tropical and subtropical regions of South America. Blindworms are the only aquatic vermiformes. The more primitive members are semi-aquatic, while the progressive members such as Typhlonectes natans are completely aquatic. Blind vermiforms have no tails, no lungs, and no scales. The aquatic members have skin-folded fins on the back, and the back of the body is flat and looks like a tail.

Tail order

There are more than 350 species of 60 genera in 10 families. It is mainly distributed in the northern region, namely Eurasia and North America. There are 37 species in 3 families in China. Adults are slender, with weak limbs. A few species have only forelimbs (eel). They have a well-developed tail throughout life, and the tail folds are thick. The skin is smooth and scale-free, the cuticles of the epidermis are thin and the skin is molted regularly. Eyes are small or subcutaneous (cave), aquatic species often lack active eyelids; no tympanic and tympanic membranes; tongues are round or oval, tongue ends are not completely free, and food cannot be turned out; fine teeth on the periphery of both jaw Have coccyx teeth. Vertebral body biconcave (lower type) or retroconcave (higher type). Males have no mating devices and are fertilized in vitro or in vivo. The skin glands or cloaca glands secrete special gases that can identify similar species when courting. Most are oviparous, and a few oviparous are born to adapt to the rapids environment. The larvae are aquatic and have three pairs of feathery outer gills. The metamorphosis is not obvious from the age of 2 to 3 years. The outer gills disappear, the gills are closed, and the neck folds are formed. Adults inhabit moist environments, mostly aquatic, and a few aquatic or terrestrial. Feeds on arthropods, snails, small fish, tadpoles and young frogs. Poor vision, predation mainly depends on smell or sidelines. Regenerate after damage to limbs and tail. ^[1]

Cryptobranchidae and Berberidae are very different in appearance and habits, but they share some primitive traits, such as in vitro fertilization and many juvenile traits, so they are also classified into the Cryptobranchia suborder, as The most primitive representative of the tail. The members of the Cryptobranchia suborder are basically limited to Asia, especially East Asia, but the Cryptobranchidae of the Cryptobranchidae family is distributed in North America and the northern borer is also distributed in northern Europe, in addition to northern Asia.

Cryptobranchidae

Cryptobrachidae has 2 genera and 3 species, namely, Cryptobrachidae (American pupae) in northeastern America, and Chinese and Japanese pupae each. Cryptobranchidae members live in living water throughout their lives. Adults still have gill fissures and skin folds on the side to increase the skin area for breathing in the water. Forelimbs have 4 toes and 5 hind toes. The three members of the Cryptobranchidae are the three largest amphibians in existence. Among them, the Chinese pupae are up to 1.8 meters in length, the Japanese pupae are 1.5 meters in length, and the pupae are 0.75 meters in length. The Chinese cockroach is also the most famous representative of China's crowtail. It is also called a baby fish because it cries like a baby crying. In Asia, the salamander's fossils were found in Europe before it was discovered by the scientific community. When the fossil of Daxun was first discovered in 1726, it was thought to be the remains of a human who died in the flood during the Noah period. Daxun was also known as a witness to the flood.

Berberidae

There are 9 genera and 35 species of Berberidae, and there are 15 genera of 7 genera in China. The members of the Berberidae family are very small and do not exceed 25 cm in length. The differences in the lifestyles of the berberidae can be divided into two major groups, one is terrestrial habitat, including berberis, northern borer, claws, etc., living on the wet ground between the forests, only returning to the stream in breeding habitats; The other is aquatic, including Beibei, mountain stream, etc., mostly live in cold mountain streams, not far from the water source. The distribution of Berberidae is basically confined to East Asia, but the polar borer is distributed in the northern part of Eurasia from the north to the Arctic Circle and west to the European part of Russia. The polar borer is also the most northern amphibian, and another species is limited to Iran.

Tadonia

Most of the members of the caudal order belong to the suborder Amaranth. This suborder represents the more advanced members of the caudal order. They are all fertilized in vivo. Some members are viviparous or oviparous, and some members maintain their larval form throughout their lives. The Tadpoles are widely distributed, but mainly concentrated in North America.

Eelidae

There are 2 genera and 3 species in the eel family, which are distributed in the southeastern United States and northeastern Mexico. The large eel, Siren lacertina, is nearly one meter in length, the small eel, Siren intermedia, is about 70 cm long, and the pseudobranch Pseudobranchus stratus is only 25 cm. The eel is the most peculiar species in the order Cerapods. It has a slender body without hind legs, looks like an eel, has external gills throughout its life, and may be in vitro fertilization. Among them, the eel and the eel have three pairs of gill fissures, four fingers However, the pseudo-eel has only one pair of gill fissures and three fingers. An eel lives aquatic life, living in shallow slow-flowing water, sometimes ashore, and when dry, secretes mucus to form hard cocoons similar to African lung fish. It is unclear whether the eel is of advanced or primitive type, and is sometimes listed separately as a suborder.

Amphibianidae

The amphibian Amphiumidae is a large mesophyllous aquatic life with gills or gill fissures throughout its life. Its body is slender like an eel and is also called a Congo eel. Its limbs are small and difficult to notice. Specially produced in North America, the body is slender and eel-like, with small limbs. The amphibian family is only distributed in the southeastern United States. There are three genera in one genus. These three species have different toe counts. Among them, the one-toed amphibian Amphiuma pholeter is only 30 cm in length, while the amphibian Amphiuma means and the amphibian amphiuma tridactylum is over one meter long.

Burrowidae

Proteidae are aquatic salamanders that maintain their larval form throughout their lives and have external gills. There are 2 genera and 6 species in the cave family, including the cave species in the European Balkan Peninsula and 5 loach species in the eastern and central United States. The cave salamander Proteus anguinus is less than 30 cm in length. Because it lives in a cave, its body is pink, and its eyes are hidden under the skin. If it leaves the cave and is exposed to the sun, the body will be black and return to the cave, it will return to a light color. The loach, Necturus maculosus, can exceed 40 cm in length and the other 4 loachs are less than 28 cm in length.

Obtusidae

Ambystomatidae has 34 genera in 2 genera and is distributed almost throughout North America from Alaska to Mexico. The adult burrowing burrowing burrows underground and returns to the water only during the breeding period. Some species in the blunt-mouthed pheasant live in water while maintaining their larval characteristics throughout life. The most famous of these species is the Mexican blister-headed owl Ambystoma mexicanum, or mexican magpie, which is only found in a lake in Mexico. Very few complete metamorphosis, and Ambystoma tigrinum mainly distributed in the United States completed metamorphosis in a short time in the eastern lowlands and maintained larval morphology in the high mountainous regions of the west. , The maximum length can reach 40 cm.

Luluidae

Dicamptonidae has 2 genera and 4 species, and is native to the northwestern United States. Similar to the blunt-mouthed pheasant, Lu Juyu also burrows underground and only returns to the water during the breeding period, and sometimes maintains the larval form for life. Both Lu Juyu and Tiger-streak blizzard belong to the largest terrestrial lynx.

Pulmonary

The members of the Plethodontidae family are completely lungless and breathe through the skin. There are about 27 genera and 220 species in the family Aphylococcus, which is the largest family in the order Auroidea. It is mainly distributed in the southern region of North America, but it can also be found in the vast areas of northern Alaska and south of Brazil and Bolivia. The species that reached Central and South America are also the only representatives of the cercaria in Central and South America. There is also a genus Speleomantes in the Anacillidae family in southern Europe. The members of the Anophelesidae family adapt to a variety of living environments, including terrestrial, aquatic, arboreal and burrowing. They have large differences in shape, such as Pseudoeurycea belli, which is more than 30 cm in length, and small such as Thorius sp. Is less than 3 cm in length.

Polygonaceae

Salamandridae is a progressive member of the genus Silia, with more than 60 genera in 14 genera. Four genera in the family Polygonum are terrestrial, and they are distributed in Europe, North Africa, and the Middle East. The remaining ten genera are mainly aquatic and widely distributed in temperate regions of the northern hemisphere. Among them, a few species in Asia enter tropical and subtropical regions. It is the most widely distributed species in the order Oculata. Most members of the family Polygonidae spawn in water, but a few are viviparous or viviparous. Polygonaceae are mostly distributed in the south of China, and many of them are endemic to China. There are many species of Polygonaceae with toxins, such as Tylototriton verrucosus, which is distributed in southwest China and neighboring Southeast Asia. Red wart wart worms are the only tailed species in northern Thailand, and some types of wart worms are endemic to China.

Ophelia

There are about 3,500 species of 303 genera in 20 families. Widely distributed on five continents, the most tropical and subtropical, some species enter the Arctic Circle and the ocean. There are 240 species in our country. Adults are short and wide, without tails. The head is slightly triangular, the neck is not obvious, the forelimbs are short, and the hind limbs are particularly developed. They have webs and are suitable for jumping or swimming. There are eyelids and tympanic membranes. The cleft palate is large, and most kinds of tongues can be turned out to eat. The ribs are underdeveloped or completely degraded; the frontal and parietal bones, ulna and radial bones, tibia and fibula all heal individually. No adapter. Multiple in vitro fertilization. Eggs lay in water and hatched larvae have tails called tadpoles. Breathing with gills, the larvae first grow hind legs, then the forelimbs, the tail gradually shortens, and finally disappears. The gills also gradually shrink and disappear, and the lungs gradually form. After metamorphosis into adults, the lungs are used for breathing. Because the structure of the lungs is relatively simple, the skin plays an important role in assisting breathing, and the skin breathing mainly emits carbon dioxide. Many frogs and toads live in farmland. Pests eat live pests, which are good for agriculture; toad cake is a traditional Chinese medicine ^[1] .

Oculoptera includes most species in modern amphibians and is the only widely distributed amphibians. The tailless members are roughly similar in shape, but far from other animals, and will not be confused with other animals in appearance alone. There is a big difference between larvae and adults. The larvae have tails and no feet, adults have no tails and have limbs. The hind limbs are longer than the forelimbs. Many species are good at jumping. The members of the caudal order are collectively called frogs and toads. The words frog and toad are not scientific divisions. In the narrow sense, they refer to members of the frog family and toad family, but the caudal order is far more than these two families. Its members are called frogs and toads. Generally speaking, those with smooth skin and relatively thin bodies are good at jumping, while those with rough skin and bloated bodies are not good at jumping. They are actually toads. The family has both types of members. Most of them can be collectively referred to as frogs when describing tailless members. Omiptera has a long history, and the Triassic has appeared. It is still prosperous until modern times. It can be seen everywhere except the polar, ocean and extremely arid deserts, but it is most abundant in tropical regions and the southern hemisphere, especially in Latin America. It's Africa. The caudal order can be divided into primitive frogs and progressive new frogs, or the frogs can be further divided into frogs, subtoads, and toads. There are also many different views on the division of sections.

The members of the Echinodermata (or further divided into the Echinodermata, Aconoptera, and Xenopus) have ribs that have not healed with the spine, which is considered to be a more primitive feature, which represents a comparison in the Apomorpha Primitive types, in which the toads are considered to be the most primitive auropoda, while the toads are considered to be a transitional type between the primitive and progressive types. The beginning frog suborder is far less abundant than the new frog suborder.

Slugidae

Leiopelmatidae, the most primitive species of cercariae, includes 1 species of 3 species in New Zealand and 1 species of caudal toad in the northwestern United States. Both are small in size, and the two are sometimes classified as separate families. Slippery toad is the only amphibian in New Zealand. It inhabits moist areas near the water and lays eggs on wet ground. When the eggs hatch, it is almost complete with metamorphosis. It is shaped like a tailed frog attached to the back of an adult frog. on. The tail-toad male has a short-tailed adapter behind him, living in the cold mountain rapids, with a suction cup on his mouth, which can be attached to the rocks of the stream without being washed away by the rapids.

Cotonidae

Discoglossidae has 15 genera in 4 genera, and its tongue is disc-shaped and cannot protrude. Discoglossus is a semi-aquatic species in Europe, North Africa, and the Middle East, with relatively bright colors. Bombina is located in the region from Europe to East Asia. It is the most primitive auropoda in China. It is poisonous and has a bright color on the abdomen. The midwifery Alytes is distributed in Europe and North Africa and lives mainly on land. It is named for its habit of carrying eggs behind its back. There are two types of Barbourina, which are distributed in the southern Philippines and Borneo. The discotonidae is sometimes divided into two separate families, the discomodidae and the bombyidae.

Posaeidae

There are 4 genera and 27 species in the family Pipidae, including the pupae of South America and the three genera of Xenopus of Africa. The members of the Pisidae family are completely aquatic, with strong and well-developed webbed hind legs, slender forelimbs without webbed, and no tongue. The pupae hatch their eggs in small sacs on their backs and leave the mother when they are metamorphosed or near completion. The genus Xenopus has claw-like horny structures and is sometimes listed as Xenopus.

Xenopusidae

Rhinophrynidae is only represented by Rhynophrynus dorsalis, which is distributed from Texas to Costa Rica. The different status of the different-tongued toads is sometimes merged into the family Poparidae, and others are listed separately as a suborder. Heterodactyla bufo burrows in the ground and swells into a sphere when in danger.

Lameidae

Pelobatidae is divided into two different subfamilies of the subfamily Lamepodidae and Ceratopodidae, which are sometimes listed as separate families. There are 2 genera and 10 species in the subfamily Laevis subfamily, and their salamander bursts are suitable for burrowing burrowing, including 4 species of laevis toads in Europe, West Asia and northwestern Africa, and 6 species of toads in North America. There are more than 70 species of 7-8 genera in the subfamily Ceratophyllidae, which are distributed in eastern, southern, and southeastern Asia. They mostly live in mountainous areas, and some of them can appear in high altitude areas. They often live near waters without burrowing. There are many species of Ceratophyllaceae in China, especially in the Hengduan Mountains. Among them, there are many species endemic to China and belong to the genera endemic to China. Among the endemic genera of the horned toad family, the genus Vibrissaphora is famous, with protrusions on its mouth, such as Chong'an moustache toad called V. liui and moose toad V. boringii called beard frog. .

Anadidae

There are 1 genus and 2 species in the family Pelodytidae, which are distributed in Western Europe and the Caucasus, respectively, and are sometimes incorporated into the subfamily of the toadidae family of the toadidae. The toad is a terrestrial frog, which looks like a typical frog and does not burrow.

New Rana

New frogs include 96% of species in the ceratops, which are distributed all over the world, and even some remote islands, but they do not appear in New Zealand. In New Zealand there are only frogs and no new frogs. The members of the New Frog suborder are mainly distributed in tropical regions and the southern hemisphere, with Latin America being the most abundant species. This page describes some members whose main distribution areas are tropical and southern hemisphere.

Toadidae

The largest family of amphibians in the family Leptodactylidae, as many as 52 genera and nearly 800 species, is distributed from the southernmost part of the Americas to Mexico and the Caribbean islands, and five species reach the southern United States. There are more than 450 species of the genus Eleutherodactylus in the family Toadidae only. The members of this genus have peculiar reproduction methods. One species is viviparous, and the other species completes metamorphosis in eggs. The hatched is a small frog Not alas. Many members of the toadidae family adapt to a variety of different lifestyles, and their appearances are different, some are like frogs, some are toads, some are arboreal like tree frogs, and some are burrowing. The other famous species of the toadidae is the Leptodactylus pentadactylus, a South American bullfrog. Its appearance and habits are similar to those of the North American bullfrog. They are large and fierce, but they are not related to each other. Belongs to the family Toadidae. Another famous large toad is Ceratophrys ornata, which is 20 cm in length and is strong and fierce. It even dares to attack animals that are many times larger than itself.

Turtles

Myobatrachidae is distributed in Oceania, and is the corresponding member of Oceania toads. Some people have also classified it into the Oceania family. There are about 20 genera and about 100 species in the family Toadidae. Like the toadidae, they include both frog-like members and some toad-like members. There are also many cave-dwelling species to adapt to the dry climate of Australia, but they are lacking. Arboreal member. The most bizarre member of the family Toadidae is Rheobatrchus silus, a new species discovered only in the twentieth century that hatched eggs in the stomach of female toads, and finally spawned small toads from the mouth. Even more strangely, Weiyuxi toad suddenly disappeared in the 1980s, just over ten years after its discovery.

Gynaecidae

Sooglossidae has only 2 genera and 3 species and is distributed in the Seychelles Islands in the Indian Ocean. Glossy frogs are small terrestrial frogs. The eggs are laid on land instead of water. The eggs hatch directly into small frogs or carry their tadpoles until they become metamorphosis. None of these attached to their backs have mouths. Do not eat. The taxonomic status of the tongue frog is uncertain, and it may be related to the turtle toad.

Biopsidae

There are only 1 genus and 4 species in the family Toadidae, which are distributed in the mountain rapids in Cape Town, the southernmost part of Africa. There are suction cups on the toe end, and suction cups on the pouting mouth. They can be attached to rocks without being washed away by the rapids. The classification status of marsh toads is uncertain and may be related to turtle toads.

Hyla

Hylidae, the second largest family of amphibians, has more than 40 genera and more than 700 species. Most members of the tree frog family are distributed in the Americas, especially in the tropical regions of the Americas. However, the few members of the largest genus Tree frogs are distributed in Eurasian continent and northwestern Africa in addition to the Americas. There are 9 species in China, and 4 Nearly 150 species of the genus are distributed in Oceania, and these members distributed in Oceania are sometimes listed separately as the frog family. The tree frog family is mainly arboreal frogs that swollen toes into suction cups. It is the main arboreal frog in the Americas and Australia. It is replaced by tree frogs and African tree frogs in Asia and Africa. As a large family, members of the tree frog family also adapt to different lifestyles. In addition to the typical arboreal frogs, there are some cave-dwelling members and land-dwelling members who live underground in both America and Oceania, but there are no members who are completely aquatic. Many members of the tree frog family have good protective colors, blending with the environment, and there are some colorful, the most peculiar is the American red-eyed frog, which only shows green when it is stationary, it is difficult to find, and it reveals its side when it moves. Bright colors to confuse the enemy.

Epidae

Centrolenidae includes 2 species of Centrolene and more than 70 species of Centrolenella, which are distributed in Latin America from southern Mexico to northeast Argentina. The frog body is 7.5 cm long and lives in a rocky waterfall, where it also lays eggs, and the eggs attach to the rocks. Small attached frogs are very small, most of them are only 3 cm, and they are mostly arboreal frogs that lay their eggs on the leaves. The abdomen skin of members of the frog family is translucent, and the internal organs can be seen faintly.

Colobidae

Colobidae Allophrynidae Allophryne ruthveni, a small arboreal frog, distributed in northern South America. The taxonomic status of the colobidae is unclear, and may be related to the toadidae, toadidae, or tree frog family.

Bufoidae

Brachycephalidae has 2 genera and 2-3 species and is distributed in coastal forests in southeastern Brazil. The cephalopods are the smallest amphibians, the smallest of which is less than a centimeter, and the others are just over a centimeter. The body of the short-headed toad is bright golden yellow, with small limbs and only three functional toes on each limb. The short-headed toad lives in the deciduous layer of the forest floor, lays eggs on land, and the eggs hatch directly into small frogs.

Toadidae

There are 2 genera and 7 species in the family Pseudidae, which are distributed in the lowland waters from Colombia to Argentina in northern and eastern South America. The most famous species of the phalaenopsis family is the singular phalaenopsis Pseudis paradoxa, which is an irrational frog. The adult frog is 7 cm long, but the tadpole is 25 cm long. Multi-fingered toads are aquatic frogs, and are buried in mud holes to survive drought.

Poisonidae

Dendrobatidae has 6 to 8 genera and 130 to 170 species, and is distributed in Latin America from Nicaragua to southeastern Brazil and Bolivia. Poison dart frogs are undoubtedly the most famous frogs in Latin America and the world. This is because they are among the most toxic animals in the world. On the other hand, because they have very bright alert colors, they are the most famous among frogs. Beautiful member. Not all members of the Poisonidae family are poisonous and colorful. Poisonous members also have different toxicities among them. One of the most toxic species is enough to kill 20,000 mice. Most poison dart frogs are small, the smallest being only 1.5 cm, but there are a few members that can reach 6 cm.

Toadidae

Bufonidae has 24 to 31 genera and 340 to 360 species, which are widely distributed throughout the world outside Oceania and Madagascar. Toads are highly adaptable animals and can live in dense forests, mountains, grasslands, and even deserts. The most common amphibians in China are probably toads. More than half of the species in the family Toadidae belong to the same genus, Bufo. The members of this genus cover almost all distribution areas of the undergraduate, and in the north it is the only representative of the undergraduate. The members of the genus Toads vary widely. The largest American sea toad reaches 25 cm in length, while some small African toads are only 1/10 the length. Although the size of toads is very different, their appearance and habits are similar. They are road animals that are slow to move and are not good at jumping. The skin is rough and highly keratinized, which makes the toad have a strong drought tolerance. Toads can secrete toxins. Can be made into toad cakes. Toads are very gluttonous, and people use them to destroy pests, but they also bring some ecological disasters. Australia has introduced sea toads to control pests in the sugar cane field, but sea toads have brought many negative impacts on local ecology. Sea toads crowd out native toads and prey on local small animals. The toxins they secrete are also important for predators. Thousands of local predators pose a threat, and sea toads have also been introduced to many other tropical areas where sugar cane is grown, mostly with some negative effects. Most of the other genera of the toadidae family have only a few members, and some appearances and habits are somewhat different from the toads. For example, Pedostibes in Southeast Asia is an arboreal toad with a light and slender body.

Frog family

Ranidae Ranidae is the third largest family of ceratoides, with more than 50 genera and 650 species. The frog family is more widespread than any other amphibian, and it is found on almost all continents, and it also appears on some islands, reaching the Arctic Circle in the north. The frog family is most prosperous in Africa. There are 18 endemic genera alone, of which there are more than 3 endemic genera on Madagascar. The frog family is also the largest member of the tailless giant frog Conrua goliath (pictured right). Africa. Frogidae are also abundant in eastern, southern, and southeastern Asia, such as the black-spotted frogs and various forest frogs common in China. However, the frogs of Europe and America only have members of the genus Rana, and they are only found in the north in South America. Frogs are only found in the extreme north of Australia, but can be seen on some Oceania islands near Australia. There are few other amphibians in these places. Frog members occupy different ecological positions here. There are two types of flat-handed frog Platymantis on the island of Fiji, which are road dwelling and arboreal. The arboreal flat-handed frogs look very similar to members of the tree frog family or tree frog family. The arboreal flat-handed frogs come in many colors Looks like different species. Other species of flat-handed frogs are also confined to islands in the Asia-Pacific region, including many arboreal members. The flat-handed frog completes metamorphosis in the egg, and the baby frog hatches out.

Tree frog family

There are 10 ~ 12 genera and 200 ~ 300 species of Rhacophoridaae. The tree frog family is very similar in appearance to the tree frog, but it has no close relationship with the tree frog and is closer to the frog family. This similarity is an adaptation to the arboreal life. The arboreal members of the other families also have similar appearances. . Tree frogs are found in tropical and subtropical regions of Asia and Africa and are also found on the island of Madagascar. The most famous tree frogs are several types of flying frogs in Asia, such as the black palm tree frog Rhacophorus nigropalmatus and the black web frog R. reiwardti. They have large feet and well developed fins, which can be used to glide in the air.

African tree frog family

The African tree frog family Hyperoliidae has 16 to 19 genera and 200 to 300 species, and is distributed on the African continent and Madagascar. There is one endemic species in the Seychelles. African tree frogs are very small, with both arboreal and road dwellings, as well as burrowing members. Many of them like to live in swamp areas and climb on reeds and other plants.

Arthropodidae

There are more than 70 species of 8 genera in the family Frogidae, which are distributed in sub-Saharan Africa and are sometimes incorporated into the family Frogidae. Some frog eggs hatch out to be metamorphosed frogs, while others still have tails. The most interesting species of the Arthropodidae is the strong frog Trichobatrachus robustus, which is distributed in the tropical rain forests from Cameroon to the Congo. Male frogs have hair-like skin derivatives on their sides and legs during the breeding season.

Frog family

There are more than 300 species of 65 genera in the family Frogidae, with the largest number of amphibians. It is found in most temperate tropical regions of the world, and in some regions, such as Madagascar and New Guinea, it has become the main local frog species, including nearly half of the local members of the Oculoptera, but in other areas Frogs are not the main frogs. Most of the Frogidae are small frogs, the smallest body length is less than 1.5 cm, but there are a few body lengths up to 8-9 cm. Many Ji Frogs live in relatively dry areas, such as the African short-headed frog, which is hard to see at ordinary times, and only becomes active during a short rainfall period. Frogs live in the leaves of tropical forests, and some are arboreal members. Arboreal members are particularly common in Madagascar and New Guinea. There are also many frogs that lay eggs on plants. Among them, all of the more than 100 species of frogs that live in Australia and New Guinea have hatched directly without hatchlings.

development

Metamorphosis of most amphibians