If not a retro a buettikoferi is still a good looking bichir. I just picked it up on a trade for an ornate that started to become a little to aggressive
the only thing that makes me think that it's a buettikoferi is the first pic and it's tale it looks exactly like my buettikoferi's tale. But the head looks a little different
That is 100% retropinnis. i have a retropinnis that looks exactly like that one. you can tell its a retropinnis by the number of dorsal fins, the pattern on it's body and the headshape. The green in yours doesn't show because of the substrate and how young the retropinnis is. the zaire green will show as it grows older.
heres a pic of my retropinnis. you can see how the pattern looks exactly alike and the headshape is the same
and here is a pic of my palmas beuttikoferi.
i only added these pics to help you see the clear difference between both species