Yunnan Lake Newt
(Cynops wolterstorffi)
EX
Overview
The Yunnan newt was found in shallow lake waters and in irrigation canals, ponds, and swampy areas. During the breeding season in April and May thousands of individuals could be seen congregating among aquatic plants in the shallow parts of the lake near the shore. At this time the species would go through a complex courtship ritual which included movements such as 'tail-fanning' from the males.

However the Yunnan newt was driven to extinction in just a few decades, being affected by pollution and habitat loss, a direct result of the growth of Kunming city, and also the introduction of exotic species. Groups surveying the lake since 1979 have been unable to find any individuals; the species was thought to be extinct at the end of the 1970s. Since then there has been just one unconfirmed record of a single individual by a fisherman in 1984.
Urgent Conservation Actions
Habitat loss, pollution, and the introduction of alien species all contributed to the decline of this species.
Distribution
Kunming Lake, Yunnan Plateau, China.
Evolutionary Distinctiveness
Order: Caudata
Family: Salamandridae
The Salamandridae (true newts and salamanders) diverged from other lineages within the order of Caudata (salamanders) around 200 million years, at the end of the Triassic period. The sub-family Pleurodelinae (the true newts) radiated during the Paleogene period, around 50 million years ago into the genera that are alive today.

The genus Cynops is made up of the seven species of fire belly newts (or fire newts), which are found in China and Japan. The group is so named because of the bright orange-red colour of the belly of these species. A number of the fire belly newts have restricted ranges, meaning that even localised threats, such as pollution and habitat loss, can have a detrimental effect on the whole population.
Description, ecology and habitat
Relatively large compared with other firebelly newts, females of the Yunnan newt measured up to 16 cm and males up to 12 cm. This species had a stout body, with large eyes and a short rounded snout. The tail had a crest on both the upper and lower edges, and a somewhat pointed end. The limbs were slender, with four un-webbed digits on the forelimbs and five on the hindlimbs. Many individuals retained gill vestiges into maturity, showing a tendency towards 'neoteny' (the condition when adults of a species retain features normally associated with young individuals).

The skin was smooth, with black as the base colour on the upper side, with an orange line down the centre of the back, and orange as the base colour on the underside, with irregular black blotches. In some cases there was orange spots on the head and down the sides of the body, and always a distinct dark orange spot behind the eye at the corner of the mouth. In the breeding season the tail of the males becomes a deep blue colour.

The Yunnan newt was a completely aquatic species found in shallow lake waters, and in irrigation canals, ponds, and swampy areas. During the breeding season in April and May thousands of individuals could be seen congregating among aquatic plants in the shallow parts of the lake, near the shore. At this time, the species would go through a complex courtship ritual which included movements such as 'tail-fanning' from the males. Eggs were deposited one by one on aquatic plants. The Yunnan newt hibernated in the deeper waters of the lake when the weather got cold.
Factors leading to extinction
Abundant in the 1950s, when thousands of individuals were seen during breeding seasons, the Yunnan newt was driven to extinction in just a few decades. Groups surveying the lake since 1979 have been unable to find any individuals, and the species was thought to be extinct at this time. Since then there has been one unconfirmed record of a single individual from a fisherman in 1984.

A combination of pressures contributed to the decline of the Yunnan newt, although the extent to which each factor caused declines is not known. The growth of Kunming city meant the reclamation of land from Kunming Lake, the only site at which the species was found, and the construction of new buildings, which caused habitat loss and pollution. As the city grew, large amounts of industrial waste and domestic sewage were disposed of in Kunming Lake, causing massive pollution. The introduction of exotic fish (such as grass carp, for food) and frogs almost certainly contributed to population declines, either via direct predation or indirectly through competition or changes to the habitat. The rearing of domestic ducks, predators of this newt species, probably caused further declines. At this time there was also a reduction of aquatic plants in the lake which meant further habitat degradation, although the cause of this vegetation loss is not known.

The combination of these anthropogenic factors means that the Yunnan newt, which was once common, is now extinct. Even local knowledge of this species is restricted to reports from a small number of older fishermen.
Links
References
AmphibiaWeb: Information on amphibian biology and conservation [web application]. 2006. Berkeley, California: AmphibiaWeb. Available: amphibiaweb. Accessed: 08 December 2006.

Frost, Darrel R. 2006. Amphibian Species of the World: an Online Reference. Version 4 (17 August 2006). Electronic Database accessible at: . American Museum of Natural History, New York, USA.

He, X.R. 1998. Cynops wolterstorffi, an analysis of the factors caused its extinction. Sichuan Journal of Zoology. 17:58-60.

IUCN, Conservation International and NatureServe. 2006. Global Amphibian Assessment. Global Amphibian Assessment. Accessed on 08 December 2006.

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