Meet the Leech - world's most incredible creature

When you heard people shout "Leech!", what will you do? I bet you'll run away as fast as possible. Yeah, people have had a bad image about leech - a bloodsucker. But lately, leech has become very popular in medical world, as a miraculous healer for many disease. To understand more about this animal, let's see what kind of animal leech is.


Leeches are annelids or segmented worms, and although closely related to the earthworms, are anatomically and behaviorally more specialized. The bodies of all leeches are divided into the same number of segments (34), with a powerful clinging sucker at each end (although the anterior, or front sucker can be very small). Body shape is variable, but to some extent depends on the degree to which their highly muscular bodies are contracted. The mouth is in the anterior sucker and the anus is on the dorsal surface (top) just in front of the rear sucker. Leeches usually have three jaws and make a Y-shaped incision.

Leeches are grouped according to the different ways they feed. One group (the jawed leeches or Gnatbobdellida) have jaws armed with teeth with which they bite the host. The blood is prevented from clotting by production of a non-enzymatic secretion called hirudin. The land leech commonly encountered by bush-walkers is included in this group. A second group (the jawless leeches or Rhyncobdellida) insert a needle-like protrusion called a proboscis into the body of the host and secrete an enzyme, hemetin which dissolves clots once they have formed. Leeches which live on body fluids of worms and small freshwater snails possess such an apparatus. A third group, (the worm leeches or Pharyngobdellida) have no jaws or teeth and swallow the prey whole. Its food consists of small invertebrates.

Most leeches are freshwater animals, but many terrestrial and marine species occur. Land leeches are common on the ground or in low foliage in wet rain forests. In drier forests they may be found on the ground in seepage moistened places. Most do not enter water and cannot swim, but can survive periods of immersion. In dry weather, some species burrow in the soil where they can survive for many months even in a total lack of environmental water. In these conditions the body is contracted dry and rigid, the suckers not distinguishable, and the skin completely dry. Within ten minutes of sprinkling with a few drops of water, these leeches emerge, fully active. Freshwater leeches prefer to live in still or slowly flowing waters, but specimens have been collected from fast flowing streams. Some species are considered amphibious as they have been observed in both terrestrial and aquatic habitats.


Now, you start to know the leeches and they are not that disgusting anyway. The more you know them, the more excited you are going to be. So stay tune at this site and learn more about leech.