West American newts

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West American newts
Californian yellow-bellied newt (Taricha torosa)

Californian yellow-bellied newt ( Taricha torosa )

Systematics
without rank: Amphibians (Lissamphibia)
Order : Tail amphibian (caudata)
Superfamily : Salamander relatives (Salamandroidea)
Family : Real salamanders (Salamandridae)
Subfamily : Pleurodelinae
Genre : West American newts
Scientific name
Taricha
JE Gray , 1850

The West American newts ( Taricha ) are a low- genus of Caudates reached by four types, the body lengths of up to 22 centimeters. They live both aquatic and terrestrial . All species are highly poisonous, they contain the poison tetrodotoxin (TTX). It is also known under the name Tarichatoxin - the genus gave it its name.

features

Taricha species are compact, medium-sized to large newts with a grainy skin. Dorsally (above) they are darkly colored, the abdominal sides are yellow to red. Rib furrows are indistinct or absent.

Gray made the generic diagnosis in the first description as follows: head broad with flat upper head, granulated. Tongue roundish and firmly grown (on the floor of the oral cavity), only slightly free at the lateral edges. Teeth on the palatine bone in two parallel rows, almost standing together. Ear glands ( parotid glands ) thickened and blistered. Skin granulated. There is a black line on the sides, but no pores in a row. The tail is elongated and flattened (laterally). The front feet have five toes, those of the hind feet have four toes. There is no webbing between the toes . Clear cusps (Apophysis) behind the eye socket (orbit).

distribution

West American water newts are widespread in North America , the animals occur in the Pacific coast region between South Alaska and southern California , possibly also in Baja California (Northwest Mexico ).

Way of life

Western Newts are iteroparous and return to the same body of water or to the same spot in a stream every spring to breed. The males of all species get smooth skin and their caudal fin enlarges during the mating season.

How the nerve toxin tetrodotoxin (TTX) is produced in Taricha TTX and kept in the body is unknown. Since TTX is an alkaloid , it is likely not the direct product of a particular gene or family of genes.

species

The genus includes four species, the type species is Taricha torosa .

Individual evidence

  1. ↑ a b c Gary M. Bucciarelli et al. : Individual fluctuations in toxin levels affect breeding site fidelity in a chemically defended amphibian. 2016, in: Proceedings of the Royal Society B: Biological Sciences , Volume 284, issue 1862. ( Online )
  2. ^ A b c d Robert C. Thomson: California Amphibian and Reptile Species of Special Concern. 2016, University Press Group Ltd, ISBN 978-0520290907 , p. 174.
  3. ↑ Lexicon of Biology at Spectrum of Science Publisher: Taricha
  4. ^ JE Gray: Catalog of the Specimens of Amphibia in the Collection of the British Museum. Part II. Batrachia Gradientia, etc. 1850. ( Online )
  5. ^ A b Darrel R. Frost: Taricha Gray , 1850. In: Amphibian Species of the World: an Online Reference, Version 6.0. Last accessed on June 8, 2016 ( online ).

Web links

Commons : Western Newts ( Taricha )  - Collection of images, videos, and audio files