Newts and European Salamanders (Salamandridae)

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Newts and European salamanders

(Salamandridae)

Class Amphibia

Order Caudata

Suborder Salamandroidea

Family Salamandridae

Thumbnail description
Long, slender body with long tail and well-developed limbs

Size
3–14 in (7–35 cm)

Number of genera, species
15 genera; 59 species

Habitat
Damp places close to ponds and streams, where breeding takes place

Conservation status
Critically Endangered: 1 species; Vulnerable: 5 species; Lower Risk/Conservation Dependent: 1 species; Data Deficient: 4 species

Distribution
Discontinuous across the Northern Hemisphere

Evolution and systematics

Salamandrids originated in the late Cretaceous or early Paleocene in Europe and later dispersed to Asia and North America. The oldest fossil salamandrids come from the Cenozoic in Europe.

The family is sometimes divided into three groups: (1) the Salamandra group (Chioglossa, Mertensiella, Salamandra, and Salamandrina), (2) the Triturus group (Cynops, Euproctus, Neurergus, Notophthalmus, Pachytriton, Paramesotriton, Taricha, and Triturus), and (3) Pleurodeles and Tylototriton.

Physical characteristics

Variable in size and appearance, most salamandrids have a long, slender, flexible body and a long tail. The limbs are well developed. Many salamandrids develop dorsal body and tail fins when they enter water. There are four toes on the fore-limbs and four or five on the hind limbs. The skin usually is rough, except in the aquatic phase, in which the skin becomes smooth, thin, and slimy, serving as a route by which oxygen is taken up from water. In the aquatic phase, the skin is shed frequently. Newts often are seen eating the discarded skin. Many species have well-developed skin glands, which often are large and prominent on the head (parotid glands). There are no costal grooves on the body. All salamandrids have toxic or distasteful skin secretions. Many of these animals are brightly colored and have distinctive defensive postures. The eyelids are moveable. Lungs are present in juveniles and adults; larvae have feathery external gills.

There is no simple way to differentiate newts and salamanders. All members of the Salamandridae are salamanders, but species that spend a prolonged period each year living in water and becoming temporarily adapted to life in water are called newts. Newts include the European Triturus species, Notophthalmus and Taricha in North America, and Cynops in eastern Asia.

Some populations of some species of salamandrids are paedomorphic, meaning they become sexually mature adults while retaining a number of larval features, such as external gills and a large, finned tail. Adults do not become terrestrial but remain in water throughout life. Paedomorphosis occurs in some European (Triturus) species and in the three North American (Notophthalmus) species. Why some populations of these species are paedomorphic is not known.

Distribution

Fragmented in Northern Hemisphere, including western and eastern North America, Europe, Asia, north Africa, and Japan.

Habitat

Salamandrids are found in a variety of habitats, including woodland, grassland, and heath. In the terrestrial phase, salamandrids need damp conditions and are generally confined to dense vegetation or crevices under rocks and logs, where conditions remain moist at the drier times of year. Because the larvae are aquatic, all salamandrids need water for reproduction. Many breed in ponds; some breed in larger lakes and others in mountain streams. The larvae are vulnerable to predation, and

many salamandrids thrive best in ponds that dry up during the summer, because these ponds cannot support populations of fish, dragonfly larvae, and other aquatic predators.

Behavior

Little is known about the behavior of salamandrids during the greater part of the time they live on land, because they are rarely seen. At least some species, notably the eastern newt (Notophthalmus viridescens) have highly developed powers of orientation that enable them to return to breeding ponds each spring. This involves the ability to detect at least one aspect of the environment that provides directional information, including smell, the position of the sun, the pattern of light polarization in the sky, and the direction of the magnetic field of the earth.

The most striking and best-studied aspect of salamandrid behavior is mating. Salamandrids achieve internal fertilization with spermatophores. During mating, the male deposits a spermatophore close to the female and then places, pushes, or entices her over it, so that the sperm is taken up into her cloaca. The female stores the sperm in special storage organs called spermathecae. The female thus controls when and where she lays the eggs.

There is much diversity among species in the behavior that accompanies sperm transfer. Many male salamandrids restrain the female before and during sperm transfer. This behavior involves grasping the female, a behavior called amplexus. European newts (Triturus) do not exhibit amplexus. Unable to

constrain the female or to control her movements, the male European newt must attract the female with the intensity and complexity of his displays. Physical differences in appearance between the sexes (sexual dimorphism) are much more marked in Triturus species than in any other tailed amphibians.

Indirect sperm transfer by means of a spermatophore has two interesting consequences. First, it is unreliable; in some species, many spermatophores are missed by females. Second, rival males can interfere. For example, in several species rival males mimic female behavior, eliciting spermatophores that are not found by females. Much of the diversity and complexity in salamandrid sexual behavior can be interpreted as adaptations that increase the reliability of sperm transfer or that counteract sexual interference (sexual defense). For example, Taricha males defend females by picking them up and carrying them away if a rival male approaches.

Chemical communication is important in salamandrid mating. Males have glands that produce courtship pheromones. In some species the pheromones are carried on the head; in others they open into the cloaca. Male pheromones alter the hormonal state of the female, making her receptive to males.

Feeding ecology and diet

All salamandrids feed on small invertebrate prey, including insects, earthworms, slugs, and snails. In the aquatic phase, newts feed on aquatic insects and are voracious predators of frog tadpoles. Feeding under water requires changes in the shape of the eye for seeing prey and of the mouth for sucking prey into the mouth. In the aquatic phase, newts develop lateral line organs in the skin. These organs enable the newt to direct tiny water currents and thus locate moving prey, even in the dark or in muddy water. Larval salamandrids eat small invertebrates, such as water fleas.

Reproductive biology

Most salamandrids are terrestrial as adults but migrate to water to breed. In terms of life history, salamandrids are a diverse family. The species vary greatly in the proportion of life spent in water and on land. Newts that lay eggs singly (e.g., Triturus and Notophthalmus) have long breeding seasons because it takes many weeks for a female to lay all her eggs. In contrast, female Taricha lay eggs in clusters and spend little time in the water.

Four European salamandrids are viviparous. That is, the eggs are retained in the female's body, where they develop into large larvae or, in some instances, miniature adults. Viviparous salamandrids have small clutches, so only a small proportion of eggs complete development. In the Caucasian salamander (Mertensiella luschani) only two, fully developed young are born after a gestation period of three or four years. The fire salamander (Salamandra salamandra), alpine salamander (S. atra), and Lanza's alpine salamander (S. lanzai) also are viviparous.

Conservation status

Most salamandrids are threatened by loss of habitat as the result of deforestation, urbanization, and intensive agriculture. Some species can coexist with humans where agriculture takes a traditional form, involving the creation of hedgerows and of ponds for livestock. Modern agricultural methods, however, are disastrous for amphibians. Ponds are filled in, hedges are torn up, and pesticides, herbicides, and chemical fertilizers kill amphibians.

The IUCN 2002 Red List includes 11 species. One species, Euproctus platycephalus, is categorized as Critically Endangered. Five are listed as Vulnerable; one as Lower Risk/Conservation Dependent; and four as Data Deficient.

Significance to humans

Because they taste bad or are toxic, salamandrids are not eaten by humans. Several species are popular as pets, in which context they are well known for the ability to escape from all but the most secure aquarium or terrarium.

Species accounts

List of Species

Golden-striped salamander
Japanese fire-bellied newt
Pyrenean brook salamander
Eastern newt
Spanish sharp-ribbed newt
European fire salamander
California newt
Great crested newt
Smooth newt
Mandarin salamander

Golden-striped salamander

Chioglossa lusitanica

taxonomy

Chioglossa lusitanica Bocage, 1864, Coimbra, Portugal.

other common names

English: Gold-striped salamander; French: Chioglosse; German: Goldstreifen salamander; Spanish: Salamandra rabilarga.

physical characteristics

The golden-striped salamander can grow to 6 in (16 cm) in length. It has a long, slender body and tail. The tail constitutes 67% of the total length. Because of its shape and rapid movements, this salamander resembles a lizard. It is dark brown and has two golden-brown stripes on the back that merge to form one stripe on the tail. On some salamanders, the stripes are broken into lines of spots. The golden-striped salamander has a long, narrow head, large eyes and a long, sticky tongue for catching prey.

distribution

Northern Portugal and northwest Spain.

habitat

The golden-striped salamander inhabits wet, mountainous areas.

behavior

Nocturnal in its habits, the golden-striped salamander is active only when it is damp and is thus confined to areas of heavy rainfall. It hibernates underground or in caves during the winter and estivates (is dormant) during dry summer periods. If attacked, the golden-striped salamander can run quickly. If

caught, it often drops its tail. The tail regrows but never reaches the previous length. This salamander produces a milky, toxic skin secretion when attacked.

feeding ecology and diet

The golden-striped salamander uses a long, protrusible tongue to feed on flies and other insects.

reproductive biology

Terrestrial for most of its life, the golden-striped salamander breeds in water, laying clumps of as many as 20 eggs in summer or autumn under rocks in springs and streams. Males develop swellings on the upper parts of the forelimbs during the breeding season. The larvae remain in water over winter.

conservation status

This rare species is listed as Vulnerable. It is threatened by habitat loss, land drainage, replacement of natural forest by plantations, and agricultural pollution.

significance to humans

None known.

Japanese fire-bellied newt

Cynops pyrrhogaster

taxonomy

Molge pyrrhogaster Boie, 1826, Nagasaki, Japan.

other common names

German: Japanischer Feuerbauchmolch; Spanish: Tritón vientre de fuego.

physical characteristics

The Japanese fire-bellied newt reaches a total length of up to 5 in (12 cm). It has a long tail with a large fin that enables the

salamander to swim powerfully. The tail of the male is tipped by a thin filament. Black above, the salamander has a bright red, spotted belly that acts as warning coloration. When attacked, the salamander produces toxic skin secretions, especially from large glands on the head.

distribution

Honshu, Shikoku, and Kyushu, Japan.

habitat

The highly aquatic Japanese fire-bellied newt inhabits ponds and pools, often reaching high population density.

behavior

Not known.

feeding ecology and diet

The Japanese fire-bellied newt feeds on wide variety of small invertebrates.

reproductive biology

Mating takes place in water and does not involve amplexus. The male stands in front of the female and may restrain her with one hind foot. In this position the male beats the tip of his tail, producing a water current that carries odor from glands in his swollen cloaca to the female's snout. Eggs are laid in water and attach to submerged vegetation.

conservation status

Not listed by the IUCN. One of the seven species in Cynops, C. wolterstorffi, once was found in China, but it has likely become extinct as the result of destruction and degradation of the aquatic habitat, particularly through chemical pollution.

significance to humans

These brightly colored newts may be found in the pet trade.

Pyrenean brook salamander

Euproctus asper

taxonomy

Triton glacialis Phillipe, 1847, Lac Bleu, Pyrenees.

other common names

French: Euprocte de Pyrénées; German: Pyrenäen Gebirgsmolch; Spanish: Tritón pirenaico.

physical characteristics

Total length is up to 5.5 in (14 cm). A slender animal with a long tail, the Pyrenean brook salamander is dark gray, brown, or black on the back, often with pale yellow markings that may form a continuous or broken stripe along the midline. The belly is yellow or orange. The tail is flattened laterally, enabling the salamander to swim well in flowing water. There is little difference in appearance between the sexes.

distribution

France and Spain in Pyrenees Mountains.

habitat

The Pyrenean brook salamander is one of three species in its genus adapted for life in fast-flowing mountain streams. It inhabits streams and mountain lakes at an altitude higher than 1,970 ft (600 m) and free of ice for more than four months each year.

behavior

Almost nothing is known about the behavior of the Pyrenean brook salamander.

feeding ecology and diet

The Pyrenean brook salamander feeds on insects and other invertebrates.

reproductive biology

During mating, members of this genus exhibit a unique form of amplexus in which the male restrains the female by wrapping his prehensile tail around her. This posture may be maintained for many hours while spermatophore transfer is achieved. Females lay 20–40 eggs under rocks. These hatch into streamlined larvae that have small external gills. The larvae undergo metamorphosis and leave the water when they are 2.0–2.4 in (50–60 mm) long.

conservation status

Not threatened. The Pyrenean brook salamander is locally common, but its range has contracted. Pollution of streams presents a risk. This salamander is protected by the Convention on the Conservation of European Wildlife and Natural Habitats (Berne Convention).

significance to humans

None known.

Eastern newt

Notophthalmus viridescens

taxonomy

Triturus viridescens Rafinesque, 1820, Lake Champlain, New York, United States.

other common names

English: Red-spotted newt; French: Tritón vert.

physical characteristics

Green above and yellow on the belly, the body is decorated with a number of bright red spots, each ringed in black. The tail is one-half the total length of the newt, which is up to 4.8 in (12 cm). The tail of aquatic adults bears a large fin, which is larger on males than on females.

distribution

Eastern North America. The black-spotted newt (Notophthalmus meridionalis) occurs only in coastal areas of Texas and Mexico. The striped newt (N. perstriatus) is confined to southern Georgia and northern Florida.

habitat

The eastern newt lives and breeds in all kinds of permanent and semipermanent water.

behavior

In its juvenile stage, which lasts one to four years, the eastern newt acquires a vivid red coloration, is highly toxic, and is called a red eft. This newt has the most complex and variable life history of any amphibian. It typically goes through four stages: egg, aquatic larva, eft, and terrestrial adult, returning annually to water to breed. There is much variation in this basic pattern, however, from one part of the range to another. Some populations have no eft stage. In other populations, some adults enter water at maturity but then do not leave. In other populations, some adults are never terrestrial but are paedomorphic. Adult eastern newts are only mildly toxic in comparison with red efts. When attacked, adults exhibit the unken reflex whereby they twist themselves into a circle to expose a bright yellow belly. Paedomorphosis is widespread in this species, in which the red and black markings take the form of stripes.

feeding ecology and diet

The eastern newt feeds on a variety of small invertebrates and on frog tadpoles.

reproductive biology

Mating behavior is complex and variable. In the breeding season, males develop large and powerful hind limbs that have horny patches on the inner surfaces. Males use the limbs to capture females in a remarkably rapid movement. The male holds the female in amplexus for a long time, stimulating her by rubbing large glands on his head over her snout. When the female is responsive, the male dismounts and deposits a spermatophore. Sometimes a quicker form of mating is used in which the male quickly "tests" the female by waving his tail in front of her. If the female responds, the male proceeds immediately to spermatophore deposition. The female lays eggs singly, attaching them to water weeds. It is thought that clutch size is 200–300 eggs.

conservation status

Not threatened. The eastern newt is by far the most widespread of the three species in this genus, although it has declined over much of its range as a result of habitat loss and pollution.

significance to humans

None known.

Spanish sharp-ribbed newt

Pleurodeles waltl

taxonomy

Pleurodeles waltl Michahelles, 1830, Cádiz, Spain.

other common names

French: Pleurodèle de Waltl; German: Spanische Rippenmolch; Spanish: Gallipato.

physical characteristics

Total length is up to 12 in (30 cm). The Spanish sharp-ribbed newt is one of the largest salamandrids, growing very large in some localities. Greenish gray with darker blotches, this newt has a row of pale spots along each side of the body. These spots mark the ends of the ribs.

distribution

Southern Spain and Portugal, coastal areas of Morocco.

habitat

The Spanish sharp-ribbed newt lives in ditches, ponds, and lakes that contain water plants. If the pond habitat dries up in summer, this newt is able to survive buried in mud.

behavior

The ribs of the Spanish sharp-ribbed newt are sharp-tipped, providing a unique form of defense. When attacked, the newt twists its body, and the sharp-tipped ribs protrude through the skin to impale the attacker. The Japanese spiny newt (Echinotriton andersoni) uses a similar form of defense.

feeding ecology and diet

The Spanish sharp-ribbed newt is a voracious predator of pond-living invertebrates.

reproductive biology

In the spring, rough patches develop on the forelimbs of males that enable the newt to grasp a female during mating. Eggs are laid in water in spring and summer.

conservation status

Not threatened. The range has contracted owing to loss of some ponds and to pollution and degradation of others.

significance to humans

None known.

European fire salamander

Salamandra salamandra

taxonomy

Lacerta salamandra Linnaeus, 1758, Nuremberg, Germany.

other common names

French: Salamandre terrestre; German: Feuersalamander; Spanish: Salamandra pintada.

physical characteristics

With a total length up to 11 in (28 cm), the European fire salamander is a robustly built animal with a relatively short tail. The species shows considerable variation in color and skin pattern. Individuals may be black with yellow markings or yellow with black or occasionally red or orange markings. The markings may be spots or stripes. The limbs are short and stout with broad toes, and the tail is cylindrical and shorter than the body. Females are slightly larger than males.

distribution

Europe.

habitat

The European fire salamander inhabits deciduous and, occasionally, coniferous forests at 656–3,280 ft (200–1,000 m).

behavior

Once it has completed its larval stage, the European fire salamander lives entirely on land. Individuals live in burrows and are territorial, defending the ground around the burrow against intrusion by neighbors. Striking color patterns act as warning coloration. Two rows of poison glands run along the body, and a cluster of poison glands is present on each side of the head behind the eyes. When attacked, fire salamanders can squirt toxin from these glands over a considerable distance.

feeding ecology and diet

Fire salamanders are active at night. They emerge from the burrow when conditions are damp to forage for worms, insects, insect larvae, and slugs.

reproductive biology

During mating, which takes place on land, the male grasps the female from below. He stimulates the female with glands on his head and when the female is receptive deposits a spermatophore. The male then flips his tail to one side so that the female falls onto it. The eggs develop inside the female and are eventually released into ponds or streams as larvae in clutches of 12–50 eggs. In a few, high-altitude populations, the larvae are retained in the female throughout development and are released as miniature adults. During development in the oviduct, larvae may be cannibalistic, eating smaller siblings. As a result, only a few individuals in each clutch of eggs complete development.

conservation status

Not threatened. The range has contracted in some areas as a result of deforestation. The population is declining in northern Spain for unknown reasons.

significance to humans

None known.

California newt

Taricha torosa

taxonomy

Triton torosa Rathke, 1833, San Francisco Bay, California, United States. Two subspecies are recognized.

other common names

German: Kalifornischer Gelbbauchmolch; Spanish: Tritón de California.

physical characteristics

Heavily-built with a total length up to 8 in (20 cm), the California newt is light to dark brown on the back and flanks and has a bright yellow, orange, or, in the case of the red-bellied newt (T. rivularis), red belly. In the terrestrial phase, the skin is dry and warty, but in the breeding season, aquatic males develop smooth, slimy skin, a pale body color, a generally plump appearance, a large tail fin, and a swollen cloaca.

distribution

California coast, Sierra Nevada. The two populations that inhabit these regions are recognized as subspecies, Taricha torosa torosa and T. torosa sierrae.

habitat

For much of their lives, California newts live underground in the burrows of ground squirrels and other animals. They emerge into the open only on rainy nights. In the spring, the newts migrate to ponds and lakes, where they can build up large populations. In northern parts of the range, California newts inhabit mesic forests. In the south they live in drier areas, including oak woodland and grassland.

behavior

All three Taricha species are extremely poisonous. The skin secretes the powerful nerve poison tetrodotoxin, which is lethal to humans. When attacked, California newts exhibit the unken reflex, raising the head and tail up and over the body, extending the limbs, and closing the eyes to reveal the bright belly.

feeding ecology and diet

The California newt feeds on a variety of small invertebrates and on eggs and larvae of its own species.

reproductive biology

Before mating, the male California newt grasps the female from above, holding her firmly beneath him with both pairs of limbs. The pair can remain in this posture (amplexus), for many hours. The male rubs glands on his chin over the female's head and body until she adopts a receptive posture, at which point the male releases the female and deposits a spermatophore. As soon as the female has picked up the spermatophore, the male grasps her again. This post-mating amplexus, which is unique to this genus, guards the female from mating attempts by other males. The female lays eggs in gelatinous clusters of seven to 30 attached to water plants. The larvae are yellowish brown with bushy external gills and large tail fins.

conservation status

Not threatened. The California newt is at risk in some parts of the range, however. In southern California, this newt is a species of special concern. Threats include loss of breeding habitat, reduction in hatching success due to increases in ultra-violet-B radiation, and predation on eggs and larvae by introduced crayfish and mosquitofish. In some places, road kill is an important cause of adult mortality. Important stretches of road sometimes are closed to allow newts to migrate safely to ponds and streams.

significance to humans

None known.

Great crested newt

Triturus cristatus

taxonomy

Triton cristatus Laurenti, 1768, Nuremberg, Germany.

other common names

French: Triton á crête; German: Kammolch; Spanish: Tritón crestado.

physical characteristics

The crested newt (total length up to 6 in [16 cm]) gets its name from the large, deeply notched crest that runs along the back of of the breeding male. The male also has a deep tail decorated with a conspicuous white stripe. As does its close relative, the green and black marbled newt (Triturus marmoratus), the crested newt has a remarkable abnormality of chromosomes. As a result of the abnormality, 50% of all young die as early embryos. This may be one reason crested newts have declined more rapidly than have European newts not handicapped in this way.

distribution

Europe.

habitat

The crested newt needs dense cover when terrestrial and large, deep ponds for breeding.

behavior

Crested newts live as long as 16 years. They spend much of their lives on land, and little is known of their habits. Crested newts are markedly distasteful. When the newt is handled, glands in the skin produce a bitter-smelling milky secretion that humans and potential predators, such as water birds and hedgehogs, find highly aversive. The bright orange and black pattern on the belly of crested newts appears to be warning coloration; predators associate the color with the distastefulness and do not attack the newt.

feeding ecology and diet

Crested newts feed on variety of small invertebrates, on frog tadpoles, and on the larvae of other newts.

reproductive biology

Adults migrate to ponds early in the spring. In Sweden they have been observed moving over snow and entering ponds that are still partially covered in ice. Females start the breeding season full of large, yolk-filled eggs, but it takes males several weeks to fully develop the deep tail and crest. Males that emerge from winter hibernation with larger fat reserves develop larger crests, and it is likely they are more attractive to females than are males with small crests.

While in breeding ponds, crested newts are secretive by day and mate at dusk. The male takes up a position in front of the female and displays to her with rhythmic beats of his tail. This wafts a pheromone, secreted by a large gland in the cloaca, toward the female's snout. The display also presents visual stimuli, particularly the white tail-stripe, which is conspicuous in dim light. If the female responds to the displays by moving toward him, the male turns and deposits a spermatophore on the floor of the pond. The female moves over it and picks it up with her open cloaca.

Two or three days after mating, the female begins to lay eggs, a process that takes many weeks. Crested newts produce 70–600 eggs, usually 150–200, laid individually carefully wrapped in the leaf of a water plant. After two to three weeks, the eggs hatch into tiny larvae, which, once they have used up the reserves of yolk, start to feed on tiny aquatic animals, such as water fleas. Larval development takes two to three months, and the young emerge from the pond as miniature adults in late summer and autumn. Female newts mate several times during the breeding season, interrupting egg-laying to replenish the supply of sperm.

conservation status

This species is listed as Lower Risk/Conservation Dependent. Like the other five species of large-bodied newts widely distributed across Europe, the population of crested newts has declined over much of the range as a result of changes to the habitat. This newt is the victim of changes in land use and agricultural practices. At the southwestern edge of its distribution, however, the crested newt is slowly expanding its range. In central France, the crested newt overlaps with the marbled newt, and hybrids between the two species are quite common. In some parts of France, the crested newt seems to be coping better than the marbled newt with new patterns of land use and is expanding into ponds previously used only by marbled newts, which are declining as a result.

significance to humans

None known.

Smooth newt

Triturus vulgaris

taxonomy

Lacerta vulgaris Linnaeus, 1758, Sweden.

other common names

English: Common newt; French: Triton ponctué; German: Teichmolch; Spanish: Tritón vulgar.

physical characteristics

The smooth newt is small and slender (length up to 4 in [11 cm]). The tail constitutes approximately one-half the total length. In the terrestrial phase, this newt is brown or dark gray.

distribution

Europe.

habitat

The habitat is variable, including woodland, grassland, parkland, hedgerows, gardens, heath, and moorland. The smooth newt breeds in small ponds.

behavior

The skin secretions of smooth newts are distasteful rather than toxic and provide little defense against predation. The newts are eaten by birds and other animals.

feeding ecology and diet

The smooth newt feeds on a wide variety of small invertebrates and on frog tadpoles.

reproductive biology

Smooth newts return to ponds to breed in early spring and remain aquatic for several months. This species, like other Triturus species, exhibits marked sexual dimorphism during the breeding season. The male develops a high dorsal crest that runs along the back and tail. This crest has a jagged edge and, like the rest of the body, is marked with large, dark spots. Parallel stripes of red and blue decorate the lower edge of the male's tail, just behind the greatly swollen and dark cloaca. The toes on the hind limbs of the male develop flaps of skin. These flaps help the male swim fast in pursuit of females.

Females lay several hundred eggs during the breeding season. Each egg is laid individually, carefully wrapped in a folded leaf. The eggs hatch into tiny carnivorous larvae, which grow over the summer months to leave the water in late summer at a length of approximately 0.8 in (2 cm). The offspring spend the next two or three years on land before they return to breed as mature adults.

conservation status

Not threatened. Although they have lost many breeding ponds throughout Europe as the result of modern methods of agriculture, smooth newts remain common in many areas. They have a remarkable ability to colonize any new pond soon after it forms.

significance to humans

None known.

Mandarin salamander

Tylototriton verrucosus

taxonomy

Tylototriton verrucosus Anderson, 1871, western Yunnan, China.

other common names

English: Crocodile newt; German: Burma-Krokodilmolch.

physical characteristics

The mandarin salamander is robustly built with a total length up to 7 in (18 cm). It has a large head with prominent glandular ridges. The long, laterally compressed tail in the aquatic phase bears a well-developed fin. The salamander is black or dark brown and is covered with two rows of large brown, orange, or red tubercles. This striking coloration is aposematic (conspicuous and serving to warn). Mandarin salamanders produce a distasteful skin secretion. The skin has a granular texture.

distribution

China, India, Nepal, Thailand, and Vietnam.

habitat

The mandarin salamander lives in hills and mountains. The natural habitat is damp woodland and forest, but the salamander also inhabits a variety of habitats that are the result of human activity, such as rice fields, tea gardens, and meadows.

behavior

Little is known.

feeding ecology and diet

The mandarin salamander feeds on a variety of small invertebrates.

reproductive biology

Terrestrial for most of its life, the mandarin salamander migrates to ponds and other water bodies in March or April when the monsoon rains begin. Mating occurs in water, the male clasping the female before spermatophore transfer. The female lays 30–60 eggs in water. There are reports that the female guards her eggs. Sexual maturity is achieved at three to five years of age.

conservation status

Not threatened. The mandarin salamander, however, has declined in abundance, primarily as the result of loss and change of its natural habitat. Collection for the pet trade has had a negative effect.