Quote from Eldavidoto clarify on my earlier post:
the flying DK mount, is the *Winged Steed of the Ebon Blade* which from the vendor has the icon of a fiery horseshoe
the standard one, has the icon of a skeletal horse, with horns.
now, lately, autobar has had these two icons reversed, yet the buff filters still show the old icons ....
as you can see (hopefully) the SS shows what i mean ...
edit : mouse is over the horse-like icon
It's not Autobar, Blizzard switched the icons. You can check from your mount tab and they are switched there too.