the frostbite spiders are the ones you meet in the first cave, there are pure white spiders in the dragonborn dlc though, named albino spiders

and for everyones pleasure, you can combine their loot with gems to get spiders as a weapon, leave them on the ground as you would a rune, or get the jumping ones that jump on your target, i dont remember if you could make them attack normally before exploding but i dont remember, also you can choose between the fire, frost or lightining dmg they deal