Leech

Pferdeegel ( Haemopis sanguisuga )

The leeches ( Hirudinea ) are one of the two subclasses of the belt worms ( Clitellata ), which in turn belong to the annelids. They include some 300 species, most of which are in fresh water and about 20% in sea and brackish water live. In humid, tropical forests mainly leeches occur.

Body characteristics

Leeches are very specialized, derived annelids. You have a fixed number of segments, which varies according to order ( Branchiobdellida 15, Acanthobdellida 29, Euhirudinea 34). After the formation of the rear suction cup no more segments emerge more, so that their number does not increase with increasing age. The suction cups are combinations of several segments; they are very muscular and glandular rich. The Coelomsäcke that occur in each segment in the original annelids, are applied only embryonic and are resolved during the adult animal. What remains is only a channel system. The secondary girdling blurred addition, the original segmentation. The eponymous feature of the belt worms ( Clitellata ), the clitellum is to look at the leeches only during reproduction. The intestine forms in the parasitic species from large ceca, where blood is stored and digested.

Inside systematics

  • Borstenegel ( Acanthobdellida ); only one way Acanthobdella peledina parasite of salmonids and is the only one equipped with bristles leeches ( on the front 5 segments).
  • Bristle lots leeches Branchiobdellida; 150 species, 0.8-10 mm long. They live on gills and surfaces of freshwater crabs and is thought to feed mainly on small algae and small animals that can be found on the surface of their host animals. However, some species are parasitic.
  • Hirudinida ( Euhirudinea ); A body divided into 34 segments, where 4 of the front and 7 form the rear suction cup. The genital opening of the male is in the ninth that of the females in the tenth segment. The coelom has a continuous channel system. Rüsselegel ( Rhynchobdelliformes ), with muscular, ausstoßbarem trunk.
  • Proboscis lots leeches Kieferegel ( Gnathobdelliformes ), with muscular jaws, which are staffed with Cuticulazähnchen.
  • Schlundegel ( Pharyngobdelliformes ), with long, muscular pharynx, which can not be everted.

In the classical system, the results of phylogenetic studies will be implemented in several ways. There are many different switched between rank levels to reflect the phylogenetic relationships. The following describes the classification of leeches within the tribe of annelids ( Annelida ) to West Heath / Rieger:

  • Class Polychaeta
  • Class Clitellata Subclass Oligochaeta
  • Subclass Hirudinea order Acanthobdellida
  • Order Branchiobdellida
  • Order Hirudinida ( Euhirudinea ) Subordination Rhynchobdelliformes ( Rüsselegel )
  • Subordination Gnathobdelliformes ( Kieferegel )
  • Subordination Pharyngobdelliformes ( Schlundegel )

Types (selection)

  • Rhynchobdelliformes ( Rüsselegel ): Small Schneckenegel ( Alboglossiphonia heteroclita )
  • Big Schneckenegel ( Glossiphonia complanata )
  • Vieräugiger Plattegel ( Hemiclepsis marginata )
  • Common fish leeches ( Piscicola geometra )
  • Schildkrötenegel ( Placobdella costata )
  • Entenegel ( Theromyzon tessulatum )
  • European platform flukes ( Helobdella europaea)
  • Gnathobdelliformes ( Kieferegel ): Pferdeegel ( Haemopis sanguisuga )
  • Medicinal leech ( Hirudo medicinalis )
  • Tyrannobdella rex
  • European land leech ( Xerobdella lecomtei ), endemic in Styria
  • Mediterranean Medicinal leech ( Hirudo verbana )
  • Pharyngobdelliformes ( Schlundegel ): Rollegel ( Hundeegel; Erpobdella octoculata )
  • Freiburger Baechle flukes ( Trocheta intermedia)
Jean-Baptiste Lamarck Cuticle
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