Haementeria ghilani or the Amazonian giant leech is the largest leech on the earth by a substantial margin, growing up to 18 inches (46 cm) in length.
Leeches are present in moist and humid areas everywhere in the world, and while most are smaller than the common person’s index finger, some can grow for much longer. But one particular species of leech can grow so large that it is taken into account a nightmare. Haementeria ghilianii, also referred to as the Amazon giant leech, that is an elusive leech that can only be present in French Guiana and a few nearby areas of Brazil, so it’s unlikely you will run into one when you don’t live there, but photos of this slimy creature ought to be enough to send shivers down your spine . While most specimens measure between 30 and 35 centimeters, exceptional specimens can grow up to 46 cm in length.
Photo: Anonyme973/Wikimedia Commons
First discovered by Italian naturalist Vittore Ghiliani in 1849, the Amazonian giant leech has achieved almost mythical status, largely due to its extraordinary size. Stories and legends of several of those parasites sucking the blood of an adult human in only a couple of hours, although there isn’t a scientific data to support this. Claims dating back to 1899 say that several leeches could kill horses and cattle by sucking their blood. From the little information we could find on the Internet, the large leech sucks blood at a rate of 4 to 15 milliliters per minute.
Unlike jawed leeches, which have a row of teeth for piercing the skin of their host, the Amazonian giant leech uses its proboscis – a pointy, needle-like appendage extending from its mouth – to pierce the skin of its victims. This 10-centimeter proboscis penetrates quite deep under the skin, but you are unlikely to feel it due to the cocktail of chemicals the leech secretes to numb the realm it pierces. Leech saliva also incorporates a robust anticoagulant that keeps the stream flowing long after separation from the host.
Haementeria ghilani it can survive for months without food, waiting patiently for unsuspecting prey to pass by. During the load loss period they appear reasonably small, but their body weight increases by 3 to 6 times per feeding, so if left to absorb blood freely they can develop into truly gigantic.
Thanks to its strong longitudinal muscles, the large Amazon leech is far tougher than it seems. According to Mark Siddall of the American Museum of Natural History, you possibly can probably step on one together with your shoe and never kill it. So you’ll need to find one other way to be sure that it’s dead when you ever come across one among these monsters.
To find out about more larger than life creatures, take a look at our posts on the Giant Flemish Rabbit, the World’s Largest Chicken, and Tommy, the World’s Largest Ox.
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