Epirus water frog
Epirus Water Frog: Adult female during the breeding season
The Epirus Water Frog or Epirusfrosch ( Pelophylax epeiroticus or Rana epeirotica ) 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. It is native in western Greece and southern Albania. Type locality is the eastern shore of Lake Ioannina, 5 kilometers south of amphitheater, Epirus region.
Features
The Epirus water frog has a body length of about 60 to 100 mm, with males sizes between 60 and 85 and the females 65-100 mm reach. The dorsal coloration is olive to bright green with irregular dark green spots; However, there are also copies brown with dark brown spots. In most cases, a light green longitudinal stripes formed on the center back. The skin is smooth with flat back glands bars. The upper side of the hind legs is also olive green to light green with dark, arc-shaped spots. The belly is whitish. It is characterized by yellowing of the flanks and loins. The webbed extend to the toes and are only slightly indented.
The males possess paired, black to dark gray vocal sacs and dark nuptial pads. The hock are triangular and small.
Externally, the Epirus water frog is not easy to distinguish from the sympatric Balkan Frog ( Pelophylax kurtmuelleri ), especially also occur hybrids of both species. A Secure identifying the Epirus water frog is his mating call, from that of the Balkan water frog striking and also from that of the hybrids differs clearly audible.
Distribution and habitat
The distribution area of Epirus water frog is restricted to the western part of Greece to the west of the Pindos Mountains, the northwestern part of the Peloponnese, the island of Corfu and on the coastal plain at Saranda in the far south of Albania. The altitudinal distribution ranges from sea level to 480 m (Ioannina lake). The Epirus water frog lives in still waters such as lakes, ponds, marshes, swamps, canals, usually with rich, low vegetation and on the banks of rivers with low flow rate, generally in areas with a wide and open Horizon. The river systems in Epirus and the two rivers Pinios and Alfios in the Peloponnese have large populations.
Pelophylax epeiroticus lives sympatric, partly syntopic with Pelophylax kurtmuelleri and with one or more types of hybrids. Always Pelophylax epeiroticus is the dominant species, followed by Pelophylax kurtmuelleri and hybrids.
Reproductive behavior
The spawning season extends from late April to early May, they may shift depending on the latitude and altitude of a population and the local weather for a few days. At high reproductive activity, the call begins in the morning at 9 clock and keeps a longer break in the evening twilight as the capture the frogs insects until midnight or longer. Calling Epirus - water frogs were observed at water temperatures from 13 to 24.5 ° C.
Mating call
The calls consist of very short pulses with intervals in between, which is why the calls creaking sound. After the calculated equations take the calls at 15 ° C water temperature 616 milliseconds and consist of 32 pulses. As the temperature increases the duration of the calls is decreased while the number of pulses per call increases. The frequency spectrum has a strong component of 1400-2400 Hz. The males usually express the calls in series.
Hybrids
Since Epirus and Balkan water frogs are associated, it comes to hybridization. The hybrids are distinguished by morphological characteristics of the parental species, but most markedly. By the mating call, which is exactly intermediate, typically between the mating calls of Pelophylax epeiroticus and Pelophylax kurtmuelleri Mating calls of hybrids with deviating characteristics lead to the assumption that also backcrosses to the two parental species take place.
System
The Epirus Water Frog belongs to the complex shape of the water frogs ( Pelophylax ), which is systematically not yet completely processed and is difficult to detect due to the many generations of hybrids. In a large part of their distribution range, the species is associated with the marsh, with which it forms and hybrids (but this happens seldom and these offspring may be infertile ). More closely related and recognized water frog species on the southern Balkan Peninsula including the Mediterranean islands are the Balkan Frog ( Pelophylax kurtmuelleri ), the Skadar water frog ( P. shqipericus ) and the Crete - water frog ( P. cretensis ). The Karpathos Frog ( P. cerigensis ) is called the shape with unclear status. In Southwest Asia also occurs Bedriagas water frog on ( Pelophylax cf bedriagae ), which should also occur in Turkey, Cyprus and on several Greek islands to become dubious views.
Endangering
The Epirus Water Frog is classified in the red list of endangered species by the IUCN as endangered ( " Vulnerable " ) because it has a relatively small area of distribution of less than 20,000 km ², and this is highly fragmented. Moreover, a growing deterioration of its habitat is found. The main threat to this species is based on the pollution and reclamation of suitable habitats by agriculture, tourism and the colonization of its habitat. In Albania, the frog will also hunted and eaten commercially.