Shale spiders are earth elemental creatures, with four spiderlike legs, that mostly only appear in Deepholm. Like normal earth elementals, shale spiders are also capable of leaving the earth plane. Some of these creatures have appeared in the Twilight Highlands devouring Elementium, and others in The Jade Forest in Pandaria devour jade. Pandaren miners refer to them as "nibblers." They apparently make nests in places such as Deepholm, where the amethyst breed is known to do so along the outer walls of the earthen zone.
Through experimentation, the mages of Dalaran have discovered that the powered remains of a crimson shale spider will greatly increase the conflagration of their fire spells.
As a companion pet
The [Tiny Shale Spider] drops off of Jadefang, a rare spider located within the Crumbling Depths caves of Deepholm. The Amethyst Shale Hatchling, Crimson Shale Hatchling, Emerald Shale Hatchling and Topaz Shale Hatchling can be obtained through pet battles.
As a hunter pet
Shale spiders are rare class of creatures usually found in Deepholm, but can be found in very specific spots in the Twilight Highlands and the Jade Forest. Only Hunters with the 31 talent point [Exotic Beasts] are be able to tame these exotic beasts.