The Knobby white spider is a large landspeeder-sized arachnid-like organism native to the swamp world of Dagobah. It has a large, lumpy body with a bloated, bulbous head, eight gnarled legs and one large stinger used to capture and sedate its prey.

One of the most bizarre organisms on Dagobah, the knobby white spider is in fact a mobile root that was part of the gnarltree's life cycle. Composed primarily of calcified wood, it will break free of its parent tree to roam the swamps and devour animals. After gathering enough nutrients, the spider will find a clear spot to anchor its legs, which will eventually transform into roots that allow the spider to grow into a towering tree.