by Dean Hougen » Tue May 27, 2008 10:55 pm
Bas Pels, thanks for the feedback! I really appreciate anyone who can help me refine this map.
Regarding the Rio Santa Lucia, it has been a few years since I created the map, and I built it on top of a rather crude, public-domain, base map, so between my faulty memory and my starting point, I can't be sure exactly what I was thinking or drawing there. However, I believe I was trying to draw the boundary between the Rio Santa Lucia and the Rio Yi, such that the Rio Yi went in with the Rio Uruguay and Rio Paraná, whereas the Rio Santa Lucia went along with rivers such as the Rio Cebollati, Rio Tacuari, etc. If this division does not make sense from an ichthyofaunal perspective, I should change my map to reflect that. If this division does make sense from an ichthyofaunal perspective but I have just drawn my line a bit in the wrong place, I should change my map to reflect that instead. Suggestions?
Bas Pels, you are right about the Rio Paraná flowing from tropical to subtropical. It is likewise true that fish from the southern end of the Rio Paraná would have trouble if moved to the northern end and vice versa. But the problem is drawing the line in the middle somewhere. Genera and species go right across the Tropic of Capricorn with little respect for latitude. There is no cut off point. There is simply a cline. Of course, one can find species and genera that jump any of the boundaries I have drawn. However, the number that do not cross these boundaries is much, much higher than the number that do cross them, which is why they are somewhat useful. I don't think I could draw such a boundary between the northern and southern Paraná.
On a related note, there is a reason I chose various shades of yellow for the Amazonas, Orinoco, Guianan Shield, and even to some extent Paraná regions. These regions seem to me to have more in common in terms of ichthyofauna than do the others.
When it comes to cichlids in particular, though, it is definitely possible to group the dark blue, purple, and dark green regions as they have no cichlids. The light green should include Crenicichla scottii, I think.
Alex, you are welcome to show my map to whomever you like and I hope it is of use in the project. Anyone is free to use it directly for hobby publications or to use it as a source of info for a commercial venture (just as anyone can use any copyrighted source -- you cannot copyright information, just the presentation of it). Of course, if it is used directly in a "for profit" venture, we'll need to talk about payment but it doesn't sound like that is your plan.
I'm glad there is interest in it.
Dean
Chair, American Cichlid Association (ACA)
President, Oklahoma Aquarium Association (OKAA)
ACA 2012 Convention in Indianapolis, IN
http://www.aca2012indy.com