Typical signs of leeches.

Leeches are representatives of annelids. The body shape of the leech is flattened. The color is black or gray-brown. Distinctive features of leeches are living in the aquatic environment and the way they feed on the blood of other animals. In connection with the method of nutrition (absorption of ready-made organic substances), the digestive system of leeches is simplified, there is a complex suction cup. When an animal bites, the leech secretes the substance hirudin into the wound, which prevents the victim’s blood from clotting.