I'll throw in my 2¥'s worth.
If you are talking about wild, non platinum etc Bichirs that are known to exist to this day, then the 2 I would say would be Polypterus Bichir Bichir "Turkana" and Polypterus Senegalus "Meridionalis".
Now if you are talking about ANY Bichirs, then I would have to say A Platinum "Dory-K" PO. Bidhir Bichir.