Well, my littlest wild Nattereri has turned a very dark purplish black. His normaly red anal fin is now purple and he has definate purple color to his body. My other wild Nattereri that I got at the same time has remained the same bronze color. I have some pictured that I will post on monday. To me, this just says that Nattereri change color depending on different factors not that there is an actual purple variant of P. Nattereri. I have had this little dude for about 10 months, and he has never displayed this color before. Very pretty, but still just a red belly. I would love to hear other opinions.