Names: medical leech, leech ordinary.
Habitat: Central and Southern Europe, Asia Minor.
Description: Medical leech - annelid class of leeches. Breathing skin, gills absent. Muscles are well developed (approximately 65% of the volume of the body). The integument called skin, which consists of a single layer pechatkovidnyh cells forming the epidermis. Outside, the epidermal layer is covered by the cuticle. The cuticle is transparent, has a protective function and is continuously growing, periodically updated in the process of molting. Molting takes place every 2-3 days. Discarded peel resembles white flakes or small white blankets. Leech elongate body, but thin shout consists of 102 rings. From the back side of the ring covered with many small papillae. On the ventral side of the papillae is much smaller, and they are less visible. The head end is narrowed compared to the rear. At both ends of the body has a special suction cup. Front sucker surrounding the mouth, it sosalny circle. It triangular shape with three strong jaws, each of which has up to 60-90 chitin teeth arranged in a semi-circular saws. Around the back is a sucker anus (poroshitsa) .On head leech has ten small eyes, arranged in a semicircle: six front and four at the back. With their help, medical leech saws through the skin to a depth of one and a half millimeters. On the edges of the jaws open ducts of the salivary glands. The saliva contains hirudin, which prevents clotting krovi.Pochki otsutstvuyut.Dva genital openings are located on the ventral side of the body, closer to the head end.
Colour: medical leech is black, dark gray, dark green, green, red and brown colors. On the back there are stripes - red, light brown, yellow or black. Boca green with yellow or olive hue. Abdomen mottled: yellow or dark green with black spots.
Size: length of 3-13 cm, body width of up to 1 cm.
Lifespan: 20 years.
Habitat: fresh water (ponds, lakes and quiet rivers) and damp places near water (clay, damp moss). Leeches like clean, running water.