Bone gnashers were a species of subterranean arachne that originated from the planet of Endor. Their name, bone gnashers, comes from their ability to rapidly consume the flesh from corpses.
During the era of the Galactic Civil War, a group of bone gnashers took up residence in the Krayt Cult Cave located close to Mos Eisley. It's believed the Krayt Cultists transported them from Endor to Tatooine.
After the Battle of Yavin around 0 BBY, Tori Radeen tasked a spacer with the mission to kill bone gnashers within the Krayt Cult Cave and retrieve six poison glands. Jabba the Hutt then used the glands to create a new poison.
Bone gnashers made an appearance in the 2003 video game Star Wars Galaxies, a massively multiplayer online roleplaying game that was developed by Sony Online Entertainment and published by LucasArts. The game shut down on December 15, 2011. The bone gnashers were introduced to the game as part of the "Legacy Quest" with the release of "Publish 25," also known as the "New Game Enhancements," on November 15, 2005.