what has about 16 legs'looks like a centipede,is found with old real fiberglass insultion in older homes .

Question

they look like dust bunnies until you turn on the lights and they
scurry very fast

Answer 1

I have seen a couple of them including one this spring in my house which does not have old fiberglass insulation. i think that part is just a coincidence.

They are much bigger than garden centipedes with longer legs which is why they can scurry that fast. They are called HOUSE CENTIPEDES. They eat spiders. They have 15 pairs of legs when full grown but start out with 4 pair and add a pair at each molt. .

Answer 2

melepedes. kind to centipedes