Skim-snakes, a type of snake displaying rainbow-colored patterns, originated from an unmapped swamp planet situated in Wild Space. This world was referred to as Graf-World by the Graf family of cartographers, who were its discoverers. These creatures inhabited the dense foliage of the tree canopy which sat high above the planet's marshy areas. In the era when the Galactic Empire held power, Lina Graf, the eldest child within the family, ventured into the planet's swamps in their family's landspeeder in an attempt to locate her brother, Milo Graf. The noise produced by the vehicle disrupted the skim-snakes residing in the canopy, which led to them abruptly emerging from the trees.
The initial appearance of skim-snakes was in Adventures in Wild Space: The Escape. This novel was penned by Cavan Scott and saw its publication in 2016.