Description
This is a slender salamander with a flat head and a rounded snout. Males 120-140 mm, females 100-130 mm total length. The upper jaw extends beyond the lower. The lips are well developed. The tail is low and oval in cross section. The extremities are slender and the front leg carries four, and the hind leg five toes. Males have a small spur on the hind legs. The male cloaca is hook-shaped, and directed posteriorly and opens dorsally. The female cloaca is more or less cone-shaped and opens distally. The skin is relatively smooth, with a few unevenly distributed warts. Coloration is variable; the dorsum can be gray, brown or olive. The back has variable numbers of brown, green, red or black spots. The spots, especially in males, can be connected to form longitudinal stripes. A vertebral stripe is white, yellowish, bright brown, rust brown or dark brown (Boehme et al 1999).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Italy

	View distribution map in BerkeleyMapper.
	View Bd and Bsal data (14 records).

E. platycephalus is endemic to the island of Sardinia. Its range is restricted to the region between Limbara Mountains in the North and Sarrabus-Mountains in the South and between Baunei in the East and Monte Linas in the West. The range has three foci: (1) the Limbara-Mountains ; (2) the Gennargentu-Mountains ; (3) the Mountains of Gerrei and Sarrabus. All three regions are situated on the eastern part of the island. With few exceptions, there are no records on the west side of the island. E. platycephalus occupies mostly calm but also running waters during its aquatic period, the length of which is determined by the climate. Small and large rivers are preferred, in areas where these rivers are calm, although it is also found in small mountain lakes and water holes. Stones on the ground are used as hiding places. The terrestrial habitat is always situated close to the water. Here you find the animals under stones, but also in root zones of bushes and trees in wasteland, in the macchia or in woodland. The species occurs between 50 and 1800 m. Most records were made in the 400-900 m zone (Gasc 1997).

Life History, Abundance, Activity, and Special Behaviors
E. platycephalus is the most aquatic member of the genus. They can be found in the water throughout the year. Usually though, they hibernate and aestivate on land in the vicinity of water. Mating can take place in April and May, after hibernation, or after aestivation in the autumn. Mating takes place in the water. The male actively searches for a female with his mouth opened. If a female is encountered the male grips her in the trunk with his jaws. The male then proceeds to find a suitable place for mating, carrying the passive female in his jaws. This searching behavior can last up to one hour. The male then curves his body so that his tail lies over the tail base of the female, and his hook-like extended cloaca lies under her tail in the cloacal region. Spermatophore transfer can take place directly or with the aid of the spurs on the hind legs of the male. The female lays her eggs individually under rocks and in cracks. She uses her elongated cloaca to position the eggs. In captivity, the eggs have been laid on the substrate or under sand. Observations on the development of eggs are only known from captivity. The eggs are 3mm in diameter, and with the gelatinous envelope they are 4-5mm in diameter. The number of eggs varies from 57 to 221. These are laid over a long period of 3 up to 5.6 months. Embryonic development takes 37.6 days on average at 15ºC, and 12.7 days at 24.5ºC. Larvae are 8.8 to 14.5 mm upon hatching. Larval development depends on temperature. At 15ºC development takes 376-453 days, whereas at 20.5ºC it takes 184-260 days. Larvae that develop in stagnant waters seem to grow larger than their conspecifics in running waters. The discovery of sexually mature animals with gill vestiges suggests a tendency toward paedomorphosis in this species (Boehme et al 1999).

Trends and Threats
E. platycephalus is highly endangered. There are only a few populations known. It may even be the rarest and most threatened salamander of Europe. In spite of intensive searches executed by various herpetologists, few historical localities could be verified. There are three probable causes for the decline of E. platycephalus: (1) Treatment of water bodies with DDT in the 1950's in the battle against malaria. (2) The introduction of trout, that may be a threat to the salamanders themselves or compete with the salamanders for food. (3) The reduction of water levels due to increasing anthropomorphic pressures. This is a direct result of the increasing demand for water due to increasing tourism and agriculture (Boehme et al 1999).

Possible reasons for amphibian decline

Drainage of habitat
Local pesticides, fertilizers, and pollutants
Introduced competitors

Comments
This species appears to be the sister taxon of Euproctus montanus from Corsica, but these two may not be sister taxa of the third species in the genus, Euproctus asper of the Pyrennes, which instead appears more closely related to some species of Triturus(Caccone et al. 1997).

References

Boehme, W., Grossenbacher, K., and Thiesmeier, B. (1999). Handbuch der Reptilien und Amphibien Europas, band 4/I:Schwanzlurche (Urodela). Aula-Verlag, Wiesbaden.

Caccone, A., Milinkovitch, M. C., Sbordoni, V. and Powell, J. R. (1997). ''Mitochondrial DNA rates and biogeography in European Newts (genus Euproctus).'' Systematic Biology, 46, 126-144.

Duellman, W. E., and Trueb, L. (1986). Biology of Amphibians. McGraw-Hill, New York.

Gasc, J.-P. (1997). Atlas of Amphibians and Reptiles in Europe. Societas Europaea Herpetologica, Bonn, Germany.

Species Account Citation: AmphibiaWeb 2021 Euproctus platycephalus: Sardinian brook salamander <https://amphibiaweb.org/species/4253> University of California, Berkeley, CA, USA. Accessed Nov 22, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Nov 2024.

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