There's a lot of stuff on our planet that we haven't discovered yet, so it could certainly be a new species. Of course, humans being humans it could also be the top of a '76 VW Bug. I'm rooting for the new species option myself, maybe one that can get us off this disastrous path we seem to be hellbent on following.
Yes, I believe that scientists could have discovered a new species. There is so much about the world we have yet to discover, especially in the realms that humans cannot easily and readily access, such as the sea and the sky. New species are constantly being discovered across the globe, and this purple orb on the ocean floor could certainly turn out to be one of them.
Scientists found a mysterious purple orb after sending a submersible discovery craft down to the ocean floor. This could well be the discovery of a new species, making this an exciting time in marine science. The ocean is a mystery that is only just beginning to reveal what lurks down below - and this is likely one such reveal!
This is a very likely scenario and is the most likely one. It is incredibly possible that the researchers have discovered a new species. There are other possible scenarios, such as a unique rock formation or an artifact that has fallen to the bottom of the ocean, but a life form is most likely.