Google 'spiders cocoon images' and you'll see a couple like it - one is a cave spider which yours clearly isn't, another is hanging from a rush, but isn't exactly the same unless it's showing an already hatched sac.
I didn't put the links as they're several lines long.
If you are going to move the cocoon, then you need to take the whole rush stalk with you, and make sure the cocoon is still hanging, and is in the same sort of place.