It is a Ghostly, Teal, Twoheaded, Carrion bird, with nice ghostly transperent looks and Blue mist and everything.
However. after taming it loses its blue mist, and becomes only slightly transperent (and loses 80% of its awesomeness)
But, inspired by the whole Oil-stained wolf Drama, I tried to find a way to make the same happen here; An awesome extra visual that you are not supposed to get. With Succes! And I was not uniquely lucky, the same procedure worked on my friend as well.
As a thanks to those people who found out about the oil-stained wolf, I will not keep this to myself.
So here is my Guide to this Blue-Mist Carrion Ghost.
I went to tame it over here (there are more possible locations):

There you will find this special circle, this procedure is the same as with the normal Angered Arakkoa Protector, you have to make a "Wing Guard" nearby Flee, he will run to this circle to spawn the Bird:

If you tame, as you normally would at that point, it will loose its blue mist/awesomeness and come out like this:
(You barely see its a Ghost or anything special. apart from that its Teal. which is nice.)

BUT, I noticed that after about 60 seconds, the Pet vanishes.
So I tried the exact same thing as with the oil wolf.
Random fact: This is not a buff or a debuff, like the oil of the wolf, making it different, so I was not sure wether this would work in any way.
It worked out perfectly though! When i started taming at 49,5 seconds after it spawned, I got the pet wíth its blue mist maintained.
(You should use the in-game stopwatch you can use at your clock.)
Try taming from 49,5 seconds after it spawned first:
*If you get the pet without its mist, you were to soon.
*If you get a fail message/sound instead, you were to late.
*If you succeed, it will not appear in your pet tray, and you will nót get a fail message for your tame, you will have to relog for your pet.
*It will nót take long, but you must not expect this to work the very first time, make timing adjustments after each fail and you are bound to have it in no-time!
here is a screenshot of me and my friend "Royalehuro" with our Blue-mist Carrion birds.
I am very delighted with my own, don't know who to name it after yet though ^.^

Happy Hunting everyone!
~Griffley - Ravenholdt
edit: I just made some improvements to the guide, thanks everyone for the positive feedback!
If anyone has questions, feel free to /whisper me on Ravenholdt-EU, or add my real-id.