Perez's Frog

Iberian water frog ( Pelophylax perezi )

The Iberian water frog ( Rana perezi or Pelophylax perezi ) is within the order of Anura to the family of the Real frogs ( Ranidae ). In addition, he is expected to follow appearance, biology and distribution of the water frogs, which are now provided by many authors in a separate genus Pelophylax. Within the not yet fully investigated water frog complex this seems to be the only representative for large parts of the Iberian Peninsula.

Features

The species is highly variable in height and coloring and drawing. Most specimens reach snout-vent lengths of five to eight centimeters. Females can sometimes also have 9.4 inches and a total average slightly larger than males. On the green, gray or brown top, there are often irregularly shaped dark spots and typical of the water frogs beaded back glands strips and a greenish longitudinal line along the center back. However, the latter may be absent also - in some populations on Mallorca is the case even at about three-quarters of all animals. The underside is whitish and covered with gray, sometimes reticulate associated stains. The paired vocal sacs in the corners of the males are colored as gray as the mating season, the Brunswick sealed Wielen; the point of the hock to the soles of the feet are flat and short. Subspecies are not distinguished.

The Iberian water frog can be easily confused with other forms of water frog complex, which together standing all likewise part - aquatil living, acute and langschnäuzige frogs with relatively narrow, slightly upturned eyes (compare against: brown frogs). Particular, there are strong similarities with the north- eastern Spain and France sympatric and syntopic occurring Graf 's hybrid frog ( Pelophylax " graphic " ) composed of crosses between Pelophylax perezi and the marsh frog ( Pelophylax ridibundus) has emerged. For a long time the Iberian water frog was also regarded as a subspecies of Seefrosches. Based on the very similar-sounding mating calls itself also can be said that a close relationship exists with the North African Sahara - water frog ( Pelophylax saharicus ). The cries of the pond frog ( Pelophylax " esculentus " ) sound similar.

Dissemination

Pelophylax perezi inhabited the whole Iberian Peninsula and parts of southwestern and southern France in fairly large continuity. ( Since in many areas of Spain and in Portugal is the only water frog species, according to current knowledge, the way in spite of the similar relatives and their own variability at least in these regions are clearly identified. ) Information on reserves in North Africa, with regard to the likelihood of confusion to doubt with Pelophylax saharicus. In addition, the species was located on different island groups in the eastern Atlantic and Mediterranean from the people, so in the Canary Islands, the Azores and Madeira. The occurrence in the Balearic Islands and Ibiza and Formentera is debatable whether it is allochthonous or natural populations.

In Mallorca, such as the Iberian water frog is one of four occurring amphibian species in addition to the endemic Mallorca- midwife toad ( Alytes muletensis ), the green toad (Bufo viridis complex) and the Mediterranean Tree Frog (Hyla meridionalis ), where the latter two probably of using people have come to the island. Many copies of Pelophylax perezi can observe about the nature reserve Albufera.

Habitat, way of life

Iberian water frogs live all year in and on waters where they bask in " water frog - style " on the banks and jump at risk with wide sets into the water. There are a wide variety of wetlands such as flood plains, rice fields, mountain lakes, peat bog, cattle troughs, wells and reservoirs populated, especially common along rivers. Only fast-flowing waters even avoid them. A certain degree of pollution and easy brackish water is tolerated. Juveniles also remove from the aquatic habitat and migrate long distances over land, probably to open up new aquatic habitat.

Pelophylax perezi feeds diurnal and nocturnal insects, earthworms, spiders, freshwater crabs and mollusks. Investigated Spanish tadpoles of the species had consumed 98 percent algae, detritus to 96 percent to 54 percent parts of higher plants, 21 percent fungal organisms, to 9.4 per cent animal organisms, to 28 percent of all pollen and sand. As predators, among other barn owls, Viper snakes, grass snakes and various water birds are called. The maximum life expectancy in the wild are four to six (ten) years, with the males probably reach more of a lesser age because of their conspicuous mating behavior.

Reproduction, individual development

After an aquatic or terrestrial hibernation between November and February / March ( in island populations omitted this part) takes the breeding season usually from February to June, but occasionally until the autumn. The males are capable thanks to their paired vocal sacs to loud calls. The mating call is to sonically resemble particularly that of the pond frog, but use "harder". In Attracted females are, as with all "modern anurans " ( Neobatrachia ) clipped from the back in the axillary region (compare Amplexus ). Later, the pair spawning places in the form of gelatinous lumps from of underwater plants, with a female produces one to two millimeters large eggs depending on the age or size or physique 800-10000 ever.

From the four to six millimeters hatchlings grow over the course of about two to four months, five to seven ( including overwintering sometimes eight to eleven) inches long zoom tadpoles before the metamorphosed animals can leave the water. Sexual maturity is sometimes attained in the first year of life, depending on the time of the conversion in the second, in males.

Protection

Legal protection status

• Habitats Directive: Annex V ( " species of Community interest " )
• Federal Species Protection Ordinance ( BArtSchV ): specially protected

Sources and further information

• Andreas Nöllert & Christel Nöllert: The amphibians of Europe. - Franckh-Kosmos, Stuttgart, ISBN 3-440-06340-2, 1992.
• Jörg Plötner: The Western Palaearctic water frogs - of martyrs of science to biological sensation. - Supplement 9 of the Journal of Feldherpetologie, Laurenti -Verlag, Bielefeld, 2006, ISBN 3-933066-26-3.