Today, TNT confirmed that it was more than just a test:
Some strange rumours have been flying around Neopia lately, and our intrepid team of Meepits has been carefully investigating them. After much searching, they have reported back and we can confirm: the rumours are true and there is, in fact, a new Neopet coming soon!

More details to be announced, but the plan is for our newest Neopet to be made available through the Premium Pet Species Change first, with a wider release to come later during a site-wide event.
Stay tuned for more info!
The image in New Features links to the Premium membership page, which has been updated to list out all current perks. Users can find a more in-depth guide to perks and other information in Jellyneo's recently revamped Premium Guide.
It seems the early release of the pet is intended to be a Premium perk, though one requiring users use up their once-per-year species change.
Jellyneo will share additional details of colors, pet styles, and other information as it comes to light. It is not yet clear whether any wearables will be retrofitted for the new species, but based on the Vandagyre it seems unlikely.