Is a leopoldi still a Leopoldi if it has 1000 spots? if it has none at all?
"Black Diamond" is an invented name.
http://roggenforum.lode.biz/forum/viewtopic.php?f=26&t=2562
It has become a hobby name for Leopoldi with more spots that are found more predominantly, but not exclusively near Sao Felix on the Southern Xingu river.
'lesser' spotted Leos and other species are also found there.
They might be more correctly called a 'Sao Felix Leopoldi' but even that has problems.
A Brazilian fisherman has a limited quota of Leopoldi rays.
A regular Leo sells for $$hundreds, a BD Leo sells for $$thousands.
http://roggenforum.lode.biz/forum/viewtopic.php?f=26&t=2590
If you were a fisherman which would you keep and which would you throw back in order to maximize your potential $$$s?
Where would you go fishing? a place where you can catch regular Leos more easily or an area where you have a better chance of getting a highly spotted one?
This creates a distorted idea of being able to classify them into sub-groups by spots and other superficial markings,and that there well defined barriers where one species suddenly becomes another.
They won't fit into neat little boxes like that.
'BD' is an attempt to impose a definition on something that cannot be defined in those absolute terms.
Best answer so far........... thank you