The Scantid is a scorpion-like creature found on certain Terran worlds.
Originally growing no more than 15cm, exposure to radioactive fallout from Terran nukes have mutated them into much larger creatures. Normally docile, a scantid is capable of tearing a normal person in half or poisioning large livestock with its many tails.
Some fear that they may have been the forerunners of certain Zerg strains, but no evidences has supported these claims. Several aggressive anti-alien groups have formed hunting parties to exterminate the species to "prevent another outbreak." As the main Terran governments possess little information on how the Zerg's origins, they are content to let these groups to hunt as long as it does not endanger civilian lives.
For more information see Scantid on the parent site.