Their body was covered by reddish brown, leathery hide and consisted of a lower, arachnid part and a humanoid torso sitting on top of it. The four hind limbs were connected to the lower arachnid part and were used exclusively for locomotion. The front pair of limbs terminated with claws and were used for attacks.
During the Galactic Civil War, the Rak'qua tribe transported a pack of mereks to the Bright Jewel system and trained them as war beasts in Station Gamma.
Following the Battle of Yavin, the collector Jener Mich tasked a group of spacers to hunt and kill an unreasonable number of mereks.