Western mud diver
| Western mud diver | ||||||||||||
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Western mud diver ( Pelodytes punctatus ) |
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| Scientific name | ||||||||||||
| Pelodytes punctatus | ||||||||||||
| ( Daudin , 1802) |
The western mud diver ( Pelodytes punctatus ) is a graceful frogfish common in Western Europe and forms one of five species of the genus mud diver ( Pelodytes ). From this in turn exclusively the family Pelodytidae consists.
features
Mud divers are very small frogs with relatively long hind legs, a flat head and vertically slit pupils . The western mud diver is only 3.5 (males) to 4.5 (females) inches long. Their upper side is colored quite variably; mostly they adorn irregular green spots on a light brown, gray or light olive green background. The back is covered with elongated warts, which often form wavy longitudinal rows and can be partly orange on the flanks. Behind the protruding eyes is a short, narrow glandular bar above the eardrum. Ear glands ( parotids ), as in the real toads , are not pronounced. The underside is white, in the hip area yellow-orange. The males develop dark oestrus calluses on the insides of the fingers and arms as well as on the chest during the mating season . Their arms are also longer and stronger than those of the females.
distribution
The range of occurrence of the species extends from northern France to southeastern Spain; Specifically, it includes France , Spain , Portugal and a small portion of north-west Italy (in Piedmont and Liguria ); the extreme southern edge of Belgium and Luxembourg will probably just be reached. The Portuguese area may be spatially separated from the Spanish occurrences. The altitude distribution ranges from sea level to middle mountain areas. The spreading is most constant in parts of Spain and France, where only the eastern edge and parts of the southwest are not populated.
In the south of the Iberian Peninsula , the Iberian mud diver ( P. ibericus ) has been considered a separate species from Pelodytes punctatus for several years .
Habitat, way of life
Mud divers occur in open to semi-open, also quite dry landscapes, which are characterized, for example, by interspersed pine or holm oak forests. There seems to be a preference for calcareous soils. During the day the animals hide under stones or in self-dug hollows. They can also climb quite well. At night they hunt for insects. The barn owl is one of their predators . Hereditary, sometimes slightly brackish ponds and sometimes even streams are sought out as spawning grounds . In the north of the range, the mud diver hibernates between November and February / March; in the south it is active all year round.
Reproduction
The breeding season in France is between late February and early April; in Portugal between November and March. In Andalusia , among other places , several spawning phases can be observed all year round. (Note: This literature reference could, however, also refer to the species Pelodytes ibericus , which will be described later !) With the help of paired internal sound bubbles, the males generate very quiet, creaking courtship calls under water that look like ("koak ... koak ... koak" ) sound. When mating, the females sometimes answer with "küh ... küh ... küh" - the calls should be similar to those of the Little Bustard or the Corn Crake .
When mating, the male clasps the female with his forelegs not in the axilla but in the lumbar region, as is typical for the “more primitive frogs” of the suborders Archaeobatrachia and Mesobatrachia . When laying spawning, the couple looks for a vertical branch or stalk in the water, on which the female uses its hind legs to wind a spawning cord a few centimeters short, three to four millimeters thick that contains 40 to 300 eggs. In total, one female can produce 1000 to 1600 eggs. These are dark gray to black on top and arranged irregularly in jelly envelopes. The tadpoles need if not hibernate intervenes, about three months until the metamorphosis to the land animal. Before that, with a total length of up to 6.5 (rarely: 9.5) centimeters, they reached quite considerable dimensions in relation to the adult animals.
Hazard and protection
The populations in north-western Italy in particular appear to be threatened by habitat destruction, environmental pollution and islanding. The IUCN does not classify the entire population of the species in its international red list as endangered despite decreasing trends, however the western mud diver is in all national states with occurrence as "endangered" (France, Belgium, Luxembourg) or at least "endangered" (other ) rated.
Legal protection status
- Federal Species Protection Ordinance (BArtSchV): particularly protected
literature
- Andreas Nöllert & Christel Nöllert: The amphibians of Europe . Franckh-Kosmos, Stuttgart 1992, ISBN 3-440-06340-2
Web links
- Photos of the Western Mud Diver at www.herp.it
- Amphibiaweb.org: Pelodytes punctatus (Engl.)
- 2008 IUCN Red List: Pelodytes punctatus (Engl .; including distribution map)