The only person I know of that he has, or had, pallifina, has these photos of it. By the looks of it a female?
Betta pallifina "Muara Teweh":
Before anyone asks; so far I have no chance of getting these fishes from him.
Tan saw the photos and said they're probably pallifina indeed. This fish should also be male and not female. Nice huh?
The owner confirmed this fish is male - in fact that's the only sex he has. I suspect that the white lower caudal and anal margins are much more distinct as in preserved specimens.