Glaucomys

Glaucomys is a genus of three flying squirrel species native to North America, distributed from Alaska to Honduras. The northern flying squirrel is larger, with belly hair that is dark at the base and white at the tip, while the smaller southern flying squirrel has belly hair that is completely white; Humboldt's flying squirrel is a cryptic species generally smaller and darker than the northern flying squirrel. All three species glide using a patagium that stretches from the wrists of the forelegs along the body to the ankles of the hind legs, and all three fluoresce pink under ultraviolet light, though the purpose of this trait is still debated.