Suggest you take a closer look at the image of the fish pattern. Acanthurus xanthopterus Does not have any “tribal” pattern on their face. Yet mine (see below) have a distinct pattern only unique to dussu.
regarding tail bone, it is not obvious in the picture but it is white (see picture below), just not very obvious but you can see a very faint hint of white.
And for Xanthopterus , they have a black tailbone and white patch around their bone. Mine has a black patch of skin surrounding it’s white tail bone which is akin to Dussumieri.
Anyway this Fish was bought from reputable a LFS, I trust their judgment, integrity and my own research.
But of course, you can call it whatever you like based on one picture, for Any prospective buyer feel free to verify personally before committing to purchase.
if you or anyone else like to have further discussion on this topic. please let me know, i can create another thread in the correct sub forum so as to not derail the sales thread any further. thanks