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Re: List of ID corrections was Ap. jurua

I highly suspect DNA studies. I remember reading an old TFH issue where the researcher examined the DNA of the neon, cardinal, and green neon tetras -- he concluded that they are not closely related. Then Weitzman did a phylogenetic study in which he examined and compared physical traits. His study provided clear evidence to what we intuitively observe -- that the three are closely related to each other and far more closely than to any other species.

The problem seems to be that we do not know yet how to draw good conclusions from DNA regarding species relationships. Two siblings (human or otherwise) will have different DNA. So if DNA varies that much, how reliable is it for species-to-species comparisons?!

So I favor phylogenetic study of species-consistent features rather than today's genetic study.

I can see how, from the perspective of your studies, that you feel splitting is safer. But from a different perspective, I feel that lumping is safer.... If I get an apisto and I don't know the collection data, I must rely upon the features to help me identify it. Usually I can do a pretty good job mapping the fish to one in "the books." And if two or three of the newer populations are not visually distinguishable (to the hobbyist), then I feel it is "safer" to label it with the more standard name instead of trying to pick one of the "population" names. As long as I'm honest with myself and with buyers that I'm a lumper, going with the "lumped" name is safer and more apt to be correct. If I must find the precise match with some location name, then I'm apt to be frustrated and far too often uncertain.

So if I have a reliable location (or new form) name, I'll keep it. Otherwise I'm quite content with a "lumped" name -- an identification that other knowledgeable aquarists can agree with -- and should reach on their own study. I know that this is not the purist approach that an ichthyologist will take -- but, gee, I'm an aquarist, not a scientist. If it has all the features of a eunotus, and it behaves like a eunotus, then how can one expect more from an aquarist than to call it a eunotus? And if there is some very subtle or internal difference that is not observable, how does that difference affect the aquarist?

--Randy  ( the lumper ;-)

At 10:09 AM 5/13/2002, Mike wrote:
Right now I prefer to play it safe & split as much as
possible. As I've said before, if you split & keep 'forms' true, then you can
always cross them when you find that 2 forms are the same species. If you cross
2 forms and then discover that they are different species, there's a chance that
you will lose 1 or both pure species in the hobby.

So the question now is whether it is better to be a lumper or a splitter.
Ongoing DNA studies are pointing to the probability that there are more distinct
species than mere geographic populations of apistos. DNA studies have already
shown that the genetic difference between A. caetei from the type locality (Rio
Caeté) and A. cf. caetei (Guamá) from the Rio Guamá are greater than the
difference in mitochondria between all species of Mbuna in Lake Malawi - and
this includes species in different genera! This is very disturbing to me
because these 2 forms are found in neighboring streams within a few miles of
each other. These 2 caetei-complex fish that are virtually identical when
preserved. The type form of A. caetei is somewhat more colorful than the Guamá
form when alive. Are these 2 forms distinct species? If we say they are the same
species, then do we lump all Malawi Mbuna into a single species?

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