Amphibians
| Amphibians | ||||||||||||
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Golden toad ( Bufo periglenes ) † |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Lissamphibia | ||||||||||||
| Haeckel , 1866 | ||||||||||||
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Under the terms amphibians (amphibia) or amphibians all land vertebrates are summarized, which, in contrast to the amniotes ("umbilical animals"), can only reproduce in water. In zoology , these terms apply primarily to ( recent ) species living today . Because the term "Amphibia" in the vertebrate paleontology is less exclusive and ( "Ur-amphibians") includes traditionally always extinct, early forms of land vertebrates, the three recent major groups of amphibians (be Anura , salamanders and caecilians ) for better differentiation occupied with the name Lissamphibia . Whenever "amphibians" are mentioned in the following, this usually refers to the Lissamphibia.
In amphibians, individual development generally takes place via an egg deposited in the water, from which an aquatile , gill-breathing larva hatches. This larva goes through a metamorphosis , at the end of which there is usually a lung-breathing adult individual who is capable of a life outside of water. The scientific name “Amphibia” (from the ancient Greek adjective ἀμφίβιος amphíbios 'double life'; formed from ἀμφί amphí , German 'on both sides' and βίος bíos , German 'life' ) refers to the two phases of life before and after the completion of the metamorphosis. Due to their physiology, all amphibian species are at least bound to habitats with high humidity, even in the adult stage . Many amphibians are nocturnal in order to protect themselves from predators and to keep water loss through the skin low.
evolution
The recent amphibians with their three large subgroups, frog amphibians (Anura, Salientia), tail amphibians (Urodela, Caudata) and crawling amphibians (Gymnophiona, Caecilia) are also known as modern amphibians (Lissamphibia) together with their immediate fossil relatives . Like modern reptiles , birds and mammals , they are evolutionary descendants of a certain group of bony fish that began in the Upper Devonian from around 380 million years ago to expand their habitat to the land areas in the immediate vicinity of inland waters (see shore leave ) . Therefore the amphibians are classified together with reptiles, birds and mammals in the group of terrestrial vertebrates (Tetrapoda).
Among the terrestrial vertebrates, the amphibians are considered to be the most primitive (“primitive”) group, among other things because they depend on water for reproduction, because some parts of their skeleton do not ossify and because of the relatively low efficiency of their lungs and their cardiovascular system. This is where they differ from the "higher" terrestrial vertebrates, the sauropsids (including birds) and mammals, collectively known as amniotes .
In their originality, the modern amphibians actually resemble to a certain extent the long extinct early terrestrial vertebrates, which are also often referred to as "amphibians" (cf. Labyrinthodontia ). However, the idea that modern amphibians are direct descendants of the first terrestrial vertebrates is outdated. Instead, it is a question of forms that have retained the mode of reproduction and the way of life of the first terrestrial vertebrates and therefore still have similarities with them, but which, especially with the frogs and sneaking amphibians, produced strongly derived representatives that are found in many Aspects differentiate from the early terrestrial vertebrates.
The origin of modern amphibians is one of the most controversial issues in vertebrate paleontology . They do not appear in fossil records until the early Triassic , more than 100 million years after the first terrestrial vertebrates and more than 50 million years after the first amniotes. The origin of modern amphibians could be narrowed down to two large groups of early terrestrial vertebrates, the temnospondyles ("cut vertebrae ") and the lepospondyles ("sleeve vertebrae"). However, it is not clear from which of the two groups the modern amphibians emerged and whether their ancestors can actually be found in only one of the two groups.
Morphological features
anatomy
Amphibians have a wide range of sizes. With a body length of barely eight millimeters, they represent the smallest known vertebrate in an adult individual of the New Guinea frog genus Paedophryne . Giant salamanders , the largest of the recent amphibians, can reach up to one and a half meters in length, but most species do not exceed 20 centimeters. The three large groups of amphibians differ relatively greatly from one another in terms of their habitus . Last but not least, this is associated with different modes of locomotion: While tailed amphibians stride or crawl on land, frog amphibians specialize in jumping. In addition, some tail and some frog species climb trees. A few species of frogs can even glide short distances. Many sneaking amphibians, however, move digging in the ground. In the water, tailed amphibians swim and dive with the help of their oar tails and frogs with the help of their long, powerful hind legs.
Frog and tail amphibians have a flat and relatively open skull , while crawling amphibians have a relatively high, compact and wedge-shaped skull . One of the most important common features of modern amphibians, which also distinguishes them from the early amphibians, the "primal amphibians", is the special structure of their teeth: a crown, usually covered with enamel , sits on a dentine base anchored in the jawbone , the so-called pedicle, with a weakly mineralized zone between the crown and the pedicle. This type of tooth structure is called pedicellate . The change of teeth occurs, as is common in the more primitive land vertebrates (including modern reptiles), several times in the course of life (polyphyodontics). Compared to the basic plan of the terrestrial vertebrates, numerous bones have been lost in the skull of modern amphibians, including those that are usually still present in modern reptiles. This applies to elements of the roof of the skull (jugals, postorbital ), the roof of the mouth ( ectopterygoid ) and the cranium ( supraoccipital, basioccipital, basic phenoid) as well as the epipterygoid.
In tailed amphibians, the two pairs of limbs tend to be of the same length; in frogs, they are clearly of different lengths. There are usually four fingers on each hand and five toes on each foot. The limbs of the sneak amphibians are completely regressed. Also within the tail amphibians there is a partial or complete reduction of limbs in the arm newts and eel newts . The bony trunk skeleton is partially reduced compared to the amniotes. The ribs are generally short, do not form a proper rib cage and there is no sternum. The frogs, whose habitus is generally strongly derived, often have no ribs at all. In addition, frog amphibians only have five to nine cervical and dorsal vertebrae, while the caudal amphibians with their rather conservative habitus have between 10 and 60. The articulation between the cervical spine and the skull is via a pair of occipital condyles - the original condition in terrestrial vertebrates is a single median condyle. The pelvis - if not receded - is attached to the transverse processes of a single pelvic vertebra.
Skin and internal organs
The skin (see also amphibian skin ) is thin, bare and barely cornified, moist and smooth or dry "warty", the subcutis is rich in mucous and poison glands - as well as pigment cells . It plays an important role in breathing , in protection against infections and enemies, and in the water balance. Amphibians do not drink, but rather absorb water through their skin and store it in lymph sacs under the skin and in the urinary bladder . It can later be returned to the organism through the urinary bladder wall.
As larvae, amphibians have gills , as adults they have simple lungs (compare swallowing breathing ), which, like skin breathing (including the special form of oral cavity breathing ), serve to exchange gases.
Amphibians are cold-blooded ; this means that they do not have a constant body temperature, but that it depends on the ambient temperature. Your heart consists of two separate antechambers and a single main chamber without a septum, which means that the lungs and body blood circulation are only partially separated.
The anus , the excretory and internal genital organs all flow into a single abdominal opening, the cloaca .
Sense organs
The eyes are important sensory organs for many species and are accordingly well developed. However, motionless objects are only inadequately perceived, whereas movements generate strong stimuli - both when searching for food and recognizing enemies as well as when finding a sexual partner.
The middle ear of the frog and tail amphibian has two potentially sound-conducting bone elements: the stapes (columella) and the operculum. The operculum is fitted into the foramen oval of the inner ear and the stapes, a simple bone rod, touches the operculum with its “rear” end (footplate) and can be fused with it. The stapes is only actually responsible for sound conduction in the case of the frogs, because only these have an eardrum. As with reptiles and birds, it is in contact with the “front” end of the stapes. However, the tympanic membrane of the frog is unlikely to be homologous to that of the amniotes . In caudal amphibians, sound is primarily perceived through the forelegs: the operculum is connected to the shoulder girdle via a permanently tense (tonic) muscle (musculus opercularis), which means that floor vibrations (substrate sound) can be conducted to the inner ear. This so-called opercular apparatus is also present in frogs, but may not be used there or only to a subordinate extent for sound perception. The operculum is missing in sneak amphibians, probably because they do not have a shoulder girdle. With them, the body cavity and the skull probably function as sound conductors.
The sense of smell is quite highly developed, especially in tailed amphibians.
Similar to fish, the larvae as well as the amphibian species that live in the water also have a lateral line system . In larvae of crawling amphibians and salamanders, electroreceptors similar to the Lorenzini ampoules of sharks have been detected.
Reproduction and Individual Development
pairing
In particular, the males of many frogs have a repertoire of vocalizations to delimit their territory and to attract females. They generate the corresponding calls using sound bladders , their larynx and lungs.
Almost all species lay eggs , so-called spawn , in gelatinous shells; some practice complicated brood care . The fertilization mainly takes place outside the womb; most tail amphibians, however, practice indirect internal insemination and fertilization.
Dependence on water
Most amphibians have to go to the water in order to reproduce - even species adapted to drought. The larvae that develop in the water , known as tadpoles in frogs , initially breathe through their outer gills. Only after some time one occurs metamorphosis one in which it is hormone-controlled to lung-breathing, skeleton-based animal transform, which can leave the waters.
Some species or specimens of species remain in a larval stage for a long time or even for their entire life (so-called temporary, partial or complete neoteny , also pedomorphic). They live permanently aquatic , such as the axolotl .
Very few, like the Headquartered in Mountain Alpine salamander are viviparous ( viviparous ) and bring previously developed young. Some other amphibians, such as the Antilles whistling frogs or many lungless salamanders , have also made themselves independent of open waters by developing larvae directly within the eggs. This is where the finished young hatch from the eggs laid on land.
Metamorphosis of the larvae
An important part of the metamorphosis of aquatic larvae is the regression of the gills and the displacement of breathing to the lungs and the surface of the skin. The skin structure changes in order to reduce water loss on land. There is also an ossification of what was previously cartilaginous substance as well as the development of extremities - with newt larvae first the front and then the rear pair of legs become visible, with tadpoles it is the other way round. The oar tails of the larvae gradually recede completely in the last phase of metamorphosis in frogs; Salamanders keep this one.
As a rule, eyelids develop (except for some fully aquatic forms) and external eardrums develop - the latter only in the frogs. The inner and outer change in shape between larva and metamorphosed animal is most drastic in the frogs (compare tadpole ).
food
While the tadpoles of the frogfish feed primarily on plants, eat detritus or even attack carrion , newt larvae and all metamorphosed amphibians are purely carnivorous . In general, live prey is ingested and swallowed whole, especially insects , arthropods , molluscs and spiders . To catch prey, many species have a sticky tongue that grows together in the front of the mouth and can pop out . Larger amphibians can also overwhelm other small vertebrates; Cannibalism (including intraspecies) is also not uncommon. However, due to their poikilothermal metabolism , amphibians often behave less as active hunters, but rather pursue a strategy of lurking or the spontaneous opportunity.
Predators
Amphibians are part of the prey pattern of many animals and sometimes form their most important food source. The adult specimens are the food of many mammals, birds and reptiles, and sometimes larger invertebrates . Apart from their sometimes very effective skin toxins , amphibians hardly have active defense strategies such as sharp teeth or claws. Often they trust in camouflage, concealment or flight, sometimes also in showing off behavior such as inflating the body or opening the mouth.
Spawn and larvae in the water are eaten by “predatory” insect larvae, by fish and water birds , but also by other amphibians. For this reason, amphibians have to provide for a very large offspring, because only a tiny fraction of the eggs and larvae produced later become sexually mature amphibians.
Systematics and taxonomy
The known amphibians of the present (Lissamphibia) can be numbered in over 7000 species. The number of the IUCN for 2017 is: 6609 species; in an "Amphibian Tree of Life" by Darrel R. Frost et al. from 2006 5948 species are named; the online database Amphibian Species of the World , also created by Darrel R. Frost and the American Museum of Natural History, distinguishes 7843 species in its current update (as of May 2018) and the website Amphibiaweb.org provides one - but is "updated daily" changing - number of 7860 (as of May 2017). Compared to somewhat older overviews, these numbers are significantly higher, which is primarily due to new methods in systematic taxonomic research. In this context, the allozyme electrophoresis , the sequencing of DNA and the refined bioacoustic analysis of vocalizations should be mentioned. As a result, the species rank is increasingly recognized for taxa that were previously only treated as subspecies, for example. However, numerous previously unknown and not described species are still being discovered, especially in tropical frogs.
At a higher taxonomic level, there is usually a subdivision into three orders with currently - depending on the overview - 54 to 61 families :
- Procedure Caudates (caudata or Urodela), so salamanders, and newts (about 700 species = about 9% of amphibians)
- Order Frogs (Anura or Salientia), i.e. frogs, toads and toads (about 6700 species = about 88%)
- Order sneak amphibians or caecilians (Gymnophiona or Apoda) (about 200 species = almost 3%)
The systematic term "Lissamphibia" should be preferred over "Amphibia". The Lissamphibia are, according to today's view, a monophyletic taxon, whereas Amphibia (including fossil representatives) are paraphyletic and represent an exclusion group: all land vertebrates (Tetrapoda) that are not amniotes .
distribution
Amphibians occur on all continents with the exception of Antarctica from the cold-temperate to the tropical zones. Their frequent dependence on fresh water (in some cases brackish water is also tolerated) limits their living space. Arid areas are only inhabited by a few specialists such as the American paddock toads , whose tadpoles have the shortest known development time of all amphibian larvae. Even cold high mountains are not a suitable habitat for most species.
The sneak amphibians (caecilians) are restricted to the tropics of Africa, Asia and America. The distribution of salamanders and newts is concentrated - with a few exceptions in South America - in the northern hemisphere. Frogs are found in almost all parts of the world and on many islands.
Species diversity is concentrated in the subtropical and tropical zones, the Neotropic , Paleotropic and the Australian region . The biogeographical region of the Holarctic is comparatively poor in species - especially the Palearctic of Eurasia.
- Tropical Latin America is the most important metropolitan area (“hot spot”) for amphibian diversity . The most species-rich nation states are Brazil (995 species) and Colombia (767 species). Also on the next ranks are South American countries: Ecuador (532 species) and Peru (559 species).
- In Asia , the three most species-rich states are China (401 species), Indonesia (339 species) and India (382 species).
- In Africa , the island of Madagascar (303 species), the Democratic Republic of the Congo (72 species) and Cameroon (206 species) have the most amphibian species on the continent.
- For Australia 441 species are currently listed. In the much smaller island state of Papua New Guinea , which is geographically also part of the Australian continent , 347 species occur.
- Europe is poor in amphibian species. The European country with the largest number of amphibian species is Italy (48 species).
Species in Europe
Cause of the low number of species
The European (sub) continent including its islands is extremely poor in amphibian species. Of the more than 7000 species worldwide, only 90 are indigenous , 40 tailed amphibians and at least 48 frog species (including three hybridogenic hybrids in the "water frogs"). On the other hand, these species often occur in more extensive distribution areas and larger populations than those in regions of the world with extremely high species diversity.
A major reason for the low diversity, especially in Central Europe, was the various Pleistocene cold ages 1.8 million to around 10,000 years ago. The glaciations of Central Europe and the high mountains displaced amphibians as well as other animals into refuges on the Iberian Peninsula , the Mediterranean Sea and the Black and Caspian Seas . (The spatial fragmentation of areas, however, also encouraged further speciation .) In warm periods , some species penetrated again into Central Europe, often having to pass orographic "gates" between mountains. The passage between the Eastern Pyrenees and the Mediterranean Sea and the Danube lowlands in the south-east acted as such expansion corridors in southwest Europe .
This biogeographical background also results in the fact that the Iberian Peninsula and France together have more than 60 percent of the European inventory of amphibians and reptiles.
Species in German-speaking countries
Germany has occurrences of 20 native taxa - 19 species and one hybrid. Specifically, there are six tailed amphibians and 14 frog species or forms (see tables). The status of the Alpine crested newt is currently unclear - it is possible that only hybrids with the northern crested newt or only allochthonous populations can be found on German territory . In the current Red List of Germany, the species is therefore no longer rated, but only considered as a neozoon for the time being. The North American bullfrog has the same status here , which has recently been able to establish itself in some places, particularly in southwest Germany, with populations that can be traced back to artificial releases. Ten amphibian species are currently nationwide as not endangered, two are on the "warning list". The remaining eight species are on the red list - that is 40 percent of the species (for the reasons, see the section entitled “Endangerment”). In addition, Germany bears strong responsibility for several species, as they either have a large part of their total area and world population there or there are particularly sensitive outpost populations. In this context, mountain newt , northern crested newt , yellow-bellied toad , natterjack toad , pond frog and agile frog should at least be mentioned.
The amphibian faunas in Switzerland and Austria differ only slightly from Germany in terms of their species spectrum. The fire-bellied toad , probably the moor frog and the garlic toad , are absent in Switzerland ; the green toad is considered extinct . The Italian agile frog and the Italian tree frog occur in Ticino as additional species . Another subspecies of the pond newt can also be found there ( Lissotriton vulgaris meridionalis ). The Alpine crested newt and the sea frog , however, were introduced by humans.
In Austria against Germany the palmate newt and the missing midwife toad ; the natterjack toad is threatened with extinction here. The Danube crested newt and the Alpine crested newt are also found in the east of the country; there is also a second subspecies of the moor frog, the Balkan moor frog.
Table amphibians in Europe
The tailed amphibians in Europe (excluding the Caucasus and Anatolia ) according to the systematics and nomenclature used here . Column “Habitats Annex”: Protection status according to the Fauna-Flora-Habitat Directive of the EU . (All European amphibian species are also “specially protected” or “strictly protected” according to the Federal Nature Conservation Act.) For species with occurrences in Germany, Austria and / or Switzerland (name is highlighted in bold ), the current classifications are given in the respective national Red List listed.
Abbreviations:
FFH Annex: II = special protection areas are to be set up for this species; IV = type of common interest to be strictly protected; V = type of community interest that may be the subject of administrative measures.
Red list: 0 (Switzerland / Austria: RE ) = extinct or lost; 1 ( CR ) = critically endangered; 2 ( EN ) = endangered; 3 ( VU ) = endangered.
R = species with geographical restriction; G ( DD ) = risk assumed, but insufficient data; NT = potentially endangered / threatened (no current hazard category); V = warning list (no current hazard category).
NE = not assessed; n ( LC ) = not in the red list / not endangered. Empty field in "Red List" = this species / subspecies does not appear here.
| German species name | Scientific Surname | family |
FFH - Annex |
Red List Germany (from 2009) |
Red List Austria (from 2007) |
Red List Switzerland (from 2005) |
|---|---|---|---|---|---|---|
| Siberian angle-toothed newt | Salamandrella keyserlingii | Hynobiidae | - | |||
| Grotto olm | Proteus anguinus | Proteidae | II, IV | |||
| Ambrosis cave salamander | Speleomantes (Hydromantes) ambrosii | Plethodontidae | II, IV | |||
| Monte Albo Cave Salamander | Speleomantes (Hydromantes) flavus | Plethodontidae | II, IV | |||
| Gené's cave salamander | Speleomantes (Atylodes) genei | Plethodontidae | II, IV | |||
| Fragrant cave salamander | Speleomantes (Hydromantes) imperialis | Plethodontidae | II, IV | |||
| Italian cave salamander | Speleomantes (Hydromantes) italicus | Plethodontidae | II, IV | |||
| Sarrabus cave salamander | Speleomantes (Hydromantes) sarrabusensis | Plethodontidae | (II, IV) | |||
| Ligurian cave salamander | Speleomantes (Hydromantes) strinatii | Plethodontidae | II, IV | |||
| Sopramonte cave salamanders | Speleomantes (Hydromantes) supramontis | Plethodontidae | II, IV | |||
| Gold stripe salamander | Chioglossa lusitanica | Salamandridae | II, IV | |||
| Pyrenean Newt | Calotriton asper | Salamandridae | II, IV | |||
| Montseny mountain newt | Calotriton arnoldi | Salamandridae | (II, IV) | |||
| Corsican mountain newt | Euproctus montanus | Salamandridae | II, IV | |||
| Sardinian mountain newt | Euproctus platycephalus | Salamandridae | II, IV | |||
| Mountain newt | Ichthyosaura alpestris | Salamandridae | - | n | NT | LC |
| Spanish newt | Lissotriton boscai | Salamandridae | - | |||
| Thread pig | Lissotriton helveticus | Salamandridae | - | n | VU | |
| Italian newt | Lissotriton italicus | Salamandridae | II, IV | |||
| Carpathian newt | Lissotriton montandoni | Salamandridae | II, IV | |||
| Pond newt | Lissotriton vulgaris | Salamandridae | - | n | NT | EN |
| Subspecies: Transylvanian pond newt | Lissotriton vulgaris ampelensis | Salamandridae | II, IV | |||
| Karpathian salamander | Lyciasalamandra helverseni | Salamandridae | (II, IV) | |||
| europ. Subspecies of: Lycian salamander | Lyciasalamandra luschani basoglui | Salamandridae | II, IV | |||
| Northern banded newt | Ommatotriton ophryticus | Salamandridae | - | |||
| Spanish ribbed newt | Pleurodeles waltl | Salamandridae | - | |||
| Alpine salamander | Salamandra atra | Salamandridae | IV | n | NT | LC |
| Aurora alpine salamander | Salamandra (atra) aurorae | Salamandridae | II, IV | |||
| Corsican fire salamander | Salamandra corsica | Salamandridae | - | |||
| Lanza's alpine salamander | Salamandra lanzai | Salamandridae | IV | |||
| South Spanish fire salamander | Salamandra longirostris | Salamandridae | ||||
| fire salamander | Salamandra salamandra | Salamandridae | - | n | NT | VU |
| Northern spectacled salamander | Salamandrina perspicillata | Salamandridae | (II, IV) | |||
| Southern Spectacled Salamander | Salamandrina terdigitata | Salamandridae | II, IV | |||
| Alpine crested newt | Triturus carnifex | Salamandridae | II, IV | VU | EN | |
| Northern crested newt | Triturus cristatus | Salamandridae | II, IV | V | EN | EN |
| Danube crested newt | Triturus dobrogicus | Salamandridae | II | EN | ||
| Buresch's crested newt | Triturus ivanbureschi | Salamandridae | ||||
| Asiatic crested newt | Triturus karelinii | Salamandridae | II, IV | |||
| Macedonian crested newt | Triturus macedonicus | Salamandridae | (II, IV) | |||
| Marble pig | Triturus marmoratus | Salamandridae | IV | |||
| Dwarf marble newt | Triturus pygmaeus | Salamandridae | (IV) |
Table frogs in Europe
The frog species of Europe (excluding the Caucasus and Anatolia ; excluding regionally established neozoa such as the North American bullfrog and the smooth clawed frog ) according to the systematics and nomenclature used here. Column “Habitats Annex”: Protection status according to the Fauna-Flora-Habitat Directive of the EU . (All European amphibian species are also “specially protected” or “strictly protected” according to the Federal Nature Conservation Act.) For species with occurrences in Germany, Austria and / or Switzerland (name is highlighted in bold ), the current classifications are given in the respective national Red List listed.
Abbreviations:
FFH Annex: II = special protection areas are to be set up for this species; IV = type of common interest to be strictly protected; V = type of community interest that may be the subject of administrative measures.
Red list: 0 (Switzerland / Austria: RE ) = extinct or lost; 1 ( CR ) = critically endangered; 2 ( EN ) = endangered; 3 ( VU ) = endangered.
R = species with geographical restriction; G ( DD ) = risk assumed, but insufficient data; NT = potentially endangered / threatened (no current hazard category); V = warning list (no current hazard category).
NE = not assessed; n ( LC ) = not in the red list / not endangered. Empty field in "Red List" = this species / subspecies does not appear here.
| German species name | Scientific Surname | family |
FFH - Annex |
Red List Germany (from 2009) |
Red List Austria (from 2007) |
Red List Switzerland (from 2005) |
|---|---|---|---|---|---|---|
| Fire-bellied toad | Bombina bombina | Bombinatoridae | II, IV | 2 | VU | |
| Italian yellow-bellied toad | Bombina pachypus | Bombinatoridae | (II, IV) | |||
| Yellow-bellied toad | Bombina variegata | Bombinatoridae | II, IV | 2 | VU | EN |
| Iberian disc beater | Discoglossus galganoi | Discoglossidae | II, IV | |||
| Corsican disc banger | Discoglossus montalentii | Discoglossidae | II, IV | |||
| Painted disc tongue | Discoglossus pictus | Discoglossidae | IV | |||
| Sardinian disc beater | Discoglossus sardus | Discoglossidae | II, IV | |||
| Iberian midwife toad | Alytes cisternasii | Alytidae | IV | |||
| Southeast Iberian Midwife Toad | Alytes dickhilleni | Alytidae | (IV) | |||
| Mallorca Midwifery Toad | Alytes muletensis | Alytidae | II, IV | |||
| Northern midwife toad | Alytes obstetricans | Alytidae | IV | 3 | EN | |
| Caucasian mud diver | Pelodytes caucasicus | Pelodytidae | - | |||
| South Iberian mud diver | Pelodytes ibericus | Pelodytidae | - | |||
| Western mud diver | Pelodytes punctatus | Pelodytidae | - | |||
| Knife foot | Pelobates cultripes | Pelobatidae | IV | |||
| Common Garlic Toad | Pelobates fuscus | Pelobatidae | IV | 3 | EN | DD |
| Syrian common toad | Pelobates syriacus | Pelobatidae | IV | |||
| Common toad | Bufo bufo complex | Bufonidae | - | n | NT | VU |
| Natterjack toad | Bufo calamita | Bufonidae | IV | V | CR | EN |
| European green toad | Bufo viridis complex | Bufonidae | IV | 3 | VU | RE |
| European tree frog | Hyla arborea | Hylidae | IV | 3 | VU | EN |
| Italian tree frog | Hyla intermedia | Hylidae | (IV) | EN | ||
| Mediterranean tree frog | Hyla meridionalis | Hylidae | IV | |||
| Iberian tree frog | Hyla molleri | Hylidae | (IV) | |||
| Eastern tree frog | Hyla orientalis | Hylidae | (IV) | |||
| Northern Italian tree frog | Hyla perrini | Hylidae | ||||
| Tyrrhenian tree frog | Hyla sarda | Hylidae | IV | |||
| Bedriaga's water frog | Pelophylax cf. bedriagae | Ranidae | ||||
| Italian water frog | Pelophylax bergeri | Ranidae | - | |||
| Karpathos water frog | Pelophylax cerigensis | Ranidae | - | |||
| Crete water frog | Pelophylax cretensis | Ranidae | - | |||
| Epirus water frog | Pelophylax epeiroticus | Ranidae | - | |||
| Pond frog | Pelophylax "esculentus" | Ranidae | V | n | NT | NT |
| Graf's hybrid frog | Pelophylax "grafi" | Ranidae | - | |||
| Italian hybrid frog | Pelophylax "hispanicus" | Ranidae | - | |||
| Balkan Edible Frog | Pelophylax kurtmuelleri | Ranidae | ||||
| Little water frog | Pelophylax lessonae | Ranidae | IV | G | VU | NT |
| Iberian water frog | Pelophylax perezi | Ranidae | V | |||
| Sea frog | Pelophylax ridibundus | Ranidae | V | n | VU | NE |
| Scutarian water frog | Pelophylax shqipericus | Ranidae | - | |||
| Moor frog | Rana arvalis | Ranidae | IV | 3 | VU | DD |
| Agile frog | Rana dalmatina | Ranidae | IV | n | NT | EN |
| Greek frog | Rana graeca | Ranidae | IV | |||
| Spanish frog | Rana iberica | Ranidae | IV | |||
| Italian frog | Rana italica | Ranidae | IV | |||
| Italian agile frog | Rana latastei | Ranidae | II, IV | VU | ||
| Asian brown frog | Rana macrocnemis | Ranidae | ||||
| Pyrenean frog | Rana pyrenaica | Ranidae | ||||
| Common frog | Rana temporaria | Ranidae | V | n | NT | LC |
Danger
statistics
Amphibians are more susceptible than many other animal groups to damaging environmental influences and changes because of their permeable skin and their property as inhabitants of biotope complexes (bodies of water and land habitats between which they commute during the course of the year). Of all the animal species on the IUCN Red List of Threatened Species worldwide, amphibians alone make up over 23 percent - compared to the total number of species, a disproportionately high number. This 360 million year old class of animals is therefore considered to be a reliable bio-indicator of the state of the earth's ecosystems .
Of the currently known amphibian species, the Red List classifies almost a third as threatened in their total stock: 489 species critically endangered , 787 species endangered ( endangered ) and 715 species endangered ( vulnerable ), a total of 1991 species. In addition, at least 39 of the “modern” species are officially listed as extinct - including the golden toad pictured above . Another 130 amphibian species have not been found for years and could also have become extinct. Around a quarter of the amphibians (1533 species) cannot currently be assessed due to a lack of data. Many more threatened species are likely to be among these.
Most of the endangered species can be found in Latin America and the Caribbean islands, i.e. in the regions naturally richest in amphibians.
In Central Europe , amphibians had long benefited from the transformation of the cultural landscape by humans, as many new, more open land habitats and bodies of water were created with small-scale farming. With the industrial revolution , but increasingly since the middle of the 20th century, stocks began to decline. Only recently have nature conservation measures been able to mitigate some negative trends, at least regionally.
causes
The causes of the high risk are the destruction or fragmentation of habitats and chemicals in the environment (including pesticides , heavy metals , nitrogen fertilizers ) (see for example chytrid fungus ). The level of pesticide contamination of individual amphibian species in the cultural landscape of Central Europe depends largely on the time of their spawning migration. For example, species that migrate late (April / May) are exposed to a higher risk of coming into contact with pesticides than species that migrate early (February / March) because pesticide use mainly occurs in late spring.
Other possible causes include rare species caught in the wild, as well as parasites and viral or fungal diseases. The effects of global climate change on habitats and the effects of UV radiation , which is increasing in many regions due to the ozone hole, are also discussed . However, it can be assumed that there is not only one cause that triggers the severe threat to the amphibian populations, but that several factors are mutually dependent or reinforcing.
In Central Europe, the high level of motor vehicle traffic on the dense road network that cuts through the landscape (compare common toad ) and the destruction or poisoning of habitats - small bodies of water and surrounding land habitats such as forests, meadows, floodplains and moors - through agriculture, industry, as well as residential, road and Hydraulic engineering is one of the greatest risk factors. An additional, little-noticed problem is that many amphibians in villages and on the outskirts of cities end up in cellar window light wells, outside cellar stairs, unsecured wells or even street drains. In these unintended traps, the animals usually starve or dry up.
Others
- Amphibians serve humans as model organisms (objects for demonstration and test animals) for teaching and research in developmental biology. Particularly noteworthy are the water frogs and clawed frogs , which were also used for pregnancy tests until the 1960s .
- In some countries, larger frog species are bred on regular farms for human consumption. But above all, wild amphibians are sometimes used on a large scale as food. The massive catch has reached threatening proportions in some regions .
- See also frog (food)
- An excessive fear of amphibians or frogs is referred to as batrachophobia .
- At WDR 2 there is the radio comedy figure Lurch-Peter Hansen .
swell
Individual evidence
- ^ Wilhelm Gemoll: Greek-German school and hand dictionary. Munich / Vienna 1965.
- ↑ David Marjanović, Michel Laurin: The origin (s) of extant amphibians: a review with emphasis on the “lepospondyl hypothesis”. Geodiversitas. Vol. 35, No. 1, 2013, pp. 207-272, doi : 10.5252 / g2013n1a8
- ↑ Eric N. Rittmeyer, Allen Allison, Michael C. Gründler, Derrick K. Thompson, Christopher C. Austin: Ecological Guild Evolution and the Discovery of the World's Smallest Vertebrate. PLoS One. Vol. 7, No. 1, 2012, e29797, doi : 10.1371 / journal.pone.0029797
- ^ Rainer R. Schoch: Amphibian Evolution - The Life of Early Land Vertebrates. Wiley-Blackwell, Chichester (West Sussex) 2014, ISBN 978-0-470-67178-8 , p. 22.
- ↑ RR Capranica: Morphology and physiology of the auditory system. Pp. 551-575 in: R. Llinas, W. Precht (ed.): Frog Neurobiology: A Handbook. Springer, Berlin / Heidelberg 1976, ISBN 978-3-642-66318-5 , p. 555.
- ↑ Michael Smotherman, Peter Narins: Evolution of the Amphibian Ear. Pp. 164-199 in: Geoffrey A. Manley, Arthur N. Popper, Richard R. Fay: Evolution of the Vertebrate Auditory System. Springer Handbook of Auditory Research, Vol. 22. Springer, New York 2004, ISBN 978-0-387-21093-3 , p. 176.
- ↑ search Amphibia The IUCN Red List of Threatened Species , accessed February 26, 2018.
- ^ Darrel R. Frost et al .: The Amphibian Tree of Life. - Bulletin of the American Museum of Natural History, 297 (2006): 370 pp., New York.
- ↑ Number of species in the Amphibian Species of the World database , accessed on August 17, 2015.
- ↑ Number of species in the Amphibiaweb.org database , accessed on May 11, 2018.
- ↑ Miguel Vences: The Amphibian Tree of Life: Ideology, Chaos or Biological Reality? Zeitschrift für Feldherpetologie, 14, Issue 2, pp. 153-162. Laurenti-Verlag, Bielefeld 2007, ISSN 0946-7998 .
- ↑ Note on the graphic: Areas of species with very small distribution areas that hardly overlap with other species cannot be clearly represented on this scale. Therefore, the color signature does not reflect, for example, that there is a higher biodiversity in southern European countries than in Central Europe.
- ↑ Interactive world map on biodiversity at Amphibiaweb.org , retrieval of the listed species numbers on April 2, 2015.
- ↑ Klaus-Detlef Kühnel, Arno Geiger, Hubert Laufer, Richard Podloucky & Martin Schlüpmann: Red list and list of total species of amphibians (Amphibia) in Germany. Pp. 259–288 in: Federal Agency for Nature Conservation (Ed.): Red List of Endangered Animals, Plants and Fungi in Germany 1: Vertebrates. Landwirtschaftsverlag, Münster 2009, ISBN 978-3-7843-5033-2 .
- ↑ Henning Steinicke, Klaus Henle, Horst Gruttke: Assessment of Germany's responsibility for the conservation of animal species using the example of amphibians and reptiles. Natur und Landschaft, Volume 77 (2002), Issue 2, pp. 72–80. Kohlhammer-Verlag, Stuttgart.
- ↑ Directive 92/43 / EEC (Fauna-Flora-Habitat Directive) in the consolidated version of January 1, 2007 , accessed on May 13, 2010
- ↑ Overview of the red list status of amphibians worldwide according to IUCN
- ↑ Patrick Lenhardt, Carsten A. Brühl, Gert Berger: Temporal coincidence of amphibian migration and pesticide applications on arable fields in spring. Basic and Applied Ecology. Vol. 16, No. 1, 2014, pp. 54-63. doi : 10.1016 / j.baae.2014.10.005 (alternative full text access : ResearchGate ); see also Andreas Zehm, University of Koblenz-Landau: Amphibians endangered by pesticides. Concerns nature. Vol. 37, No. 1, 2015, pp. 11–12 ( HTML version in the weblog nature conservation bayern ).
literature
- Günther E. Freytag, Bernhard Grzimek, Oskar Kuhn, Erich Thenius (eds.): Lurche . In: Grzimeks Tierleben, Vol. 5: Fish 2, Lurche. Licensed edition in dtv, Munich 1980, ISBN 3-423-03204-9 .
- Dieter Glandt: Pocket dictionary of amphibians and reptiles in Europe. Quelle & Meyer, Wiebelsheim 2010, ISBN 978-3-494-01470-8 .
- Rainer Günther (Ed.): The amphibians and reptiles of Germany . Gustav Fischer Verlag, Jena 1996, ISBN 3-437-35016-1 .
- Robert Hofrichter (Ed.): Amphibians. Evolution, anatomy, physiology, ecology and distribution, behavior, threat and endangerment. Naturbuch Verlag, Augsburg 1998, ISBN 3-89440-299-7 .
- Andreas & Christel Nöllert: The amphibians of Europe . Franckh-Kosmos, Stuttgart 1992, ISBN 3-440-06340-2 .
- Gerhard Thielcke, Claus-Peter Herrn, Claus-Peter Hutter, Rudolf L. Schreiber: Save the frogs. pro natur-Verlag, Stuttgart 1983, ISBN 3-88582-003-X .
- Peter Weygoldt: Amphibians. In: Lexicon of Biology. Vol. 1. Herder-Verlag, Freiburg 1983, ISBN 3-451-19641-7 .
Web links
(partly sources)
