Apparently, these were posted on Serebii on accident and then deleted...
Not sure if this was true or if someone made a mock-up image of Serebii and claiming he did this, but I wouldn't rule out the possibility.
For those of you unaware, "Diansii", "Borukenion", and "Fuupa" are names that were found in July registered alongside other Japanese names that turned out to all be X/Y Pokemon, including the Starter Evolutions and Zygarde.
EDIT: Apparently these links:
All have placeholder images set, while anything past 721 does not, indicating that there is indeed the possibility Serebii's database is prepared to incorporate them.