Potamon potamios

Potamon potamios

Potamon potamios is a local crayfish from the family of Potamidae. There have been described several subspecies.

Features

Potamon potamios is a relatively large freshwater crab, her carapace achieved depending on the subspecies has a width of about 55 to 70 mm, a length of 44-57 mm and a height of 26-34 mm. The carapace is slightly convex, smooth and shiny. Its front side edge has many very small, rounded teeth. The forehead is steeply inclined and has two smooth, shiny, grained cloth on the upper side. The crista is sharp to flat, S- shaped Cervikalfurche and then dissolved in grains. The abdomen in the male is elongated triangular with slightly convex sides, the abdomen of the female is wider, as with all crabs.

The two shears are relatively large and may be slightly different. They have high cutting, leave a gap when closing and are alternately occupied by a larger and three to four smaller nodes. Carpus and merus are rough on the outside by scale-like pustule. The walking legs are stocky.

The first gonopods of males have an elongated conical end member, which is slightly curved in the central area outwards. The next link is long and slightly curved. The flexible region between these two elements is conspicuous bilobed. The gonopods are used as distinguishing features to the other species of the genus.

Distribution and habitat

The species is widely, but spread very fragmented in the eastern Mediterranean. Their natural habitat is in the fresh waters of the Mediterranean islands of Rhodes, Naxos, Karpathos, Crete and Cyprus, Turkey, Syria, Jordan, Lebanon, Israel (including the Palestinian territories of Gaza and the West Bank ) and Egypt ( Sinai Peninsula ). In Greece, Turkey overlap the distribution areas of the four mutually very similar species Potamon potamios, Potamon ibericum, Potamon fluvial rhodium and Potamon.

Way of life

Potamon potamios lives in lakes and rivers. A threat to their habitats emanates from the people. More and more sources are framed and derived in the more arid areas of the eastern Mediterranean to obtain water. Potamon potamios is regarded as semi- terrestrial, it also occurs in semi-arid climates. While the medium-sized copies left in the night the water to search for food, larger ones are also active day and to observe both in the water and on the shore banks.

System

Potamon potamios belongs within the family of Potamidae to the subfamily Potaminae whose distribution area of Europe and North Africa extends to northern India and Myanmar. Within the genus Potamon Potamon is potamios counted for Nominat - subgenus Potamon, so Potamon ( Potamon ) potamios.

Subspecies

By disjunct distribution in each other far flung areas and isolation on islands, there was a small mixing of the gene pool of this kind, so that numerous species could emerge. There are currently seven subspecies considered valid:

  • Potamon potamios ssp. CYPRION Pretzmann, 1962
  • Potamon potamios ssp. Karamani Pretzmann, 1962
  • Potamon potamios ssp. Karpathos Ghiavarini, 1934
  • Potamon potamios ssp. kretaion Ghiavarini, 1934
  • Potamon potamios ssp. palaestinense Bott, 1967
  • Potamon potamios ssp. potamios ( Olivier, 1804)
  • Potamon potamios ssp. beautiful manni Pretzmann, 1986 ( Naxos )
Guillaume-Antoine Olivier Desert climate
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