Dwarf marble newt
| Dwarf marble newt | ||||||||||||
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Dwarf marble newt ( Triturus pygmaeus ), |
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| Triturus pygmaeus | ||||||||||||
| ( Wolterstorff , 1905) |
The dwarf marble newt ( Triturus pygmaeus ), sometimes also called the southern marble newt , is a tailed amphibian from the genus Triturus that occurs in the southwest of the Iberian Peninsula . The specific epithet is derived from the Latin word pygmaeus with the meaning "dwarfish" and refers to the small size of the animals. Until 2001 they were considered a subspecies of the marble newt ( Triturus marmoratus ). On the basis of detailed, comparative morphological and genetic analyzes, the dwarf marble newt was granted species status.
features
The total length of the dwarf marble newt averages 106.5 millimeters for males and 116.5 millimeters for females. Particularly small populations (males 90 millimeters maximum, females 98 millimeters) occur in the Coto de Doñana National Park . The tail length is about 45 to 50% of the total length. The back and flanks, both in the water and in the country costume, show a black to brownish pattern of spots of different sizes on a light green background, some of which are connected like a net. The ventral side is yellowish in color and has some black and white spots. During the rutting season, the male forms a moderately high back crest, which merges without interruption into the tail with a wide, light / dark alternating border and shows no clear indentations. The females are missing the back crest and tail hem. With them, the back line is designed as a continuous orange-colored band, which in the males, however, is weaker and alternates between orange and black tones. The head is slightly longer than it is wide and ends with a narrow muzzle. The parotids stand out clearly.
Similar species
With a total length of up to 160 millimeters, the marble pig is significantly larger than the dwarf marble pig. In addition, the similar species occurs approximately north of the 40th parallel , the dwarf marble newt, however, south of it. A geographical overlap between the two species in this area is extremely small.
distribution and habitat
The dwarf marble newt occurs in the southwest of the Iberian Peninsula. The northern limit of distribution runs roughly on a line from the Portuguese Atlantic coast via Aveito and Leiria and south along the Iberian Scheidegebirge . The species is absent in regions further east of Spain . If suitable spawning waters are available, their habitat includes forest, heather and meadow landscapes as well as macchia zones . It can also be found on agricultural land, but needs sufficient hiding places.
Way of life
When the autumn rains set in in October and November, the newts go to their spawning grounds. The main spawning season in the south of the range primarily covers the months of December and January. In the northern areas of the area, it does not start until February or March. The female attaches 148 to 382 (maximum 776) eggs to aquatic plants, often over a month. At water temperatures between 15 and 20 ° C, the 9 to 11 millimeter long, diurnal and nocturnal larvae hatch after 10 to 15 days. After about three months and a length of 37 to 56 millimeters, they reach the stage of metamorphosis . On land, dwarf marble newts hide under stones, roots or dead wood as well as in caves and feed on various invertebrates (Evertebrata) at night . During their stay in the water, they prefer to eat small crustaceans (Crustacea), the proportion of which, when the stomach contents were examined, was up to 85.6%.
Danger
Increasing industrialized agriculture, lowering of the groundwater level, road construction, afforestation with non-local plants as well as increasing wildfires are developing as potential hazards for the dwarf marble pig. Also introduced fish species as well as the introduced red American crayfish ( Procambarus clarkii ) are a danger for the newts. The species is therefore classified as " near threatened " by the World Conservation Organization IUCN .
Individual evidence
- ↑ M. Garcia-Paris, B. Arana & P. Herrero (2001): Molecular characterization of the contact zone between Triturus pygmaeus and T. marmoratus (Caudata: Salamandridae) in Central Spain and their taxonomic assessment. - Revista Espafiola de Herpetologia 15, 2001, pp. 115-126
- ↑ a b Pilar Herrero, Albert Montori & Begoña Arano: Triturus pygmaeus (Wolterstorff, 1905) - Southern Marble Newt , Handbook of Reptiles and Amphibians in Europe Founded by Wolfgang Bohme Volume 4 / IIA: Tailed amphibian (Urodela) IIA, edited by Kurt Grossenbacher and Burkhard Thiesmeier , AULA-Verlag Wiebelsheim, 2003, pp. 543-553
- ↑ a b c d e f g Rudolf Malkmus: Distribution and choice of spawning grounds for the dwarf marble newt Triturus pygmaeus (Wolterstorff, 1905) , amphibia, 11 (2), 2012, pp. 20-27
- ↑ C. Diaz-Paniagua: Interacciones en la alimentación de las larvas de dos especies de tritones (Triturus marmoratus y Triturus boseal) , Doñana Acta Vertebrata, 7, 1980, pp. 29-39
- ^ IUCN Red List
Web links
- herpetofauna.at - males and females in water costume
- server-he.de/artenliste - Females in traditional costume