Leech Dossier

Sawyer Hghilianii

Common Name Haementeria
Group Invertebrates
Species Haementeria laetus
Time Holocene
Diet Sanguinivore
Temperament Passive - Aggressive
XP For Kill 1 XP
PC Release Date June 2, 2016 (v242.0)
Xbox Release Date June 15, 2016 (v737.0)
Tameable No
Rideable No

It is difficult to be angry with Haementeria Laetus, despite its rather terrible nature. The creature has practically no intelligence, and just attaches to any nearby living flesh in an attempt to drain that creature's blood.

Removing Haementeria requires precision bladework, or access to an open flame. Both of these can be nearly as dangerous to the host as to the leech itself. Once Haementeria attaches to a host, it drains blood at a rapid pace, and the host experiences hunger, losses of health, and lowered stamina. Some Haementeria are also carriers for a dangerous disease I've dubbed 'Swamp Fever', which persists permanently beyond the leech's own lifespan. Few creatures on the island are transmitters for this disease, and it can ultimately be cured with a rare medicine.


While Haementeria is not intelligent enough to be tamed, and does not provide a resource any tribe would need in large quantities, it is always useful to keep a few around for antidotes. When processed properly, Haementaria venom can be made into powerful antivenom!

— The Dossier

The Haementeria or Leech is a small sanguinivorous invertebrate found on the Ark. The Leech comes in two variants, the Leech and Diseased Leech.

Wikipedia has a more detailed and comprehensive article on Leech


One of the most revolting creatures that inhabits the island is Haementeria laetus, a leech that grows as long as a man's arm. A blood parasite, the soft-bodied creature actively seeks out hosts in the swamps it calls home, propelling itself with fluttering fins and latching on with a mouth full of sharp rasping teeth.

In the wild, leeches are the primary vector for a debilitating disease commonly known as swamp fever.




  • The Dossier was revealed on February 8th, 2016.
  • In The Center, Leeches are more commonly found in deep water that the player can submerge him or herself in.

Trivia not relevant for the game

  • The Leech's genus, Haementeria, refers to a modern genus of leeches which includes the Amazon Giant Leech, which can grow up to 17 inches.


Gameplay Images



ARK One Year Anniversary and Patch 242 Enter the Dragon!

ARK One Year Anniversary and Patch 242 Enter the Dragon!