This is about speculation on the greyed out icon next to the Vrykul in the archeology interface. From what I have seen, it is yet to be explained and is a probable placeholder. Blizzard has stated on many occasions that archeology was designed with the ability to expand in mind. The fun part is guessing what civilization it could be. Here's my guesses:
Pandaren (I wish)
Dragons - This would actually make sense from lore, but artifacts would be challenging to make up (at least for me)
Goblins or Gnomes - they could make some fun stuff with them
Ogres
Ethereals - In Outland and other places that might be added in expansions
Tauren - might not be much
Murlocs - Ha!