How to delete reusable content pane?

I accidentally created duplicate reusable content panes.

How do I delete the duplicates?
Update: I figured out the answer to this question. Administration > Structure > Fieldable Panels Panes > click on "list" for the relevant bundle. I still don't know the answer to the other question, though...

If I delete a pane, and it's in use somewhere, will it disappear from the page?

Thanks!

Also, I couldn't figure out which version of panopoly my website is using (it came installed with Open Atrium 7.x-2.65), so I just chose one randomly for the version field -- let me know how I can find out the version and I'll update it. Sorry!