"Justice" wrote in message
news:9o4gf.153496$Io.26657@clgrps13...
NetMax wrote:
Most fish have a tremendous amount of 'cousins'. The Neon tetra comes
from a huge family of tetras - danios, mbuna, corys, rainbowfish all
have huge 'families'. Plecos are so diversified that new discoveries
are all simply numbered (ie:L121, L122 etc). Even fish which we might
think are unique, such as the Siamese fighting fish come from a very
large 'family' (Genus Betta). The same for Guppies, Firemouths, Geos
and many others we might think unique. At the other extreme, for
whatever evolutionary reason, certain fish are practically 'alone' in
this world (thinking along the lines of shape, behaviour and niche).

For these loners, was the process of evolution so harsh that every
other variant was exterminated, or perhaps their environments were so
inhospitable to having more than one of something? If their survival
was so precarious, it gives me the feeling that it's only by the
slimmest of chances that we have them here today, and that many unique
fishes simply did not survive long enough to have been seen by modern
man. Or perhaps these unique fishes were so successful that they
simply mastered the niche they found and prevented any competition
through diversification.

My vote for the top three unique fish would start with the Angelfish,
which incidentally is classified into more than one species, but among
the experts, this topic is hotly debated and rarely agreed upon. At a
glance, it started with Pterophyllum scalare & P.altum with
discussions about P.eimekei - but now it's P.scalare, P.altum,
P.leopoldi and P.dumerilli.

Experts aside (and I'm sidetracking), these evolutionary variants are
fairly 'recent', and if experts have trouble distinguishing between
them, then perhaps we shouldn't worry about it ;~). In practical
terms, 99.99% of the Angelfish sold today are P.scalare in color/fin
morphs (marble, black, golden, veiltail etc) and the remaining .01%
are wild caught P.altums (silver wild coloration/marking)..imo.

My vote #2 goes to the Pompadourfish (what?). Now more commonly
called the Discus ;~). Here again, perhaps the experts are splitting
hairs, and there are two species Symphysodon discus and
S.aequifaciatus and various sub-species (willischwartzi, axelrodi,
haraldi etc), but essentially, besides slight variations in color
patterns and ray counts, it's the same fish, and there are many color
morphs.

Vote #3 is not so obvious. perhaps the Elephant-nose fish or Mono
(Monodactylus argenteus with one cousin, the Sebae). Hatchetfish are
quite unique (Silver or Marble species). Anyone have any other
suggestions?

Interesting, and I have somthing for you the Coelacanth is a 400
million yeas old has no relations, especilly to the fact that is has
limbs like our arms. No I'm not crazy I saw it on NOVA. science thinks
that this is a link to Darwen's idea that all life came from water.
Here check it out.

http://www.pbs.org/wgbh/nova/fish/anatomy.html

Yup definitely holds the record (imo) for most unique. Thanks for the
link. That notocord is a real throwback. I *was* thinking about
freshwater fish we could keep in an aquarium though ;~), and if we open
this up to marine life, then it will get really weird (how about the
Seahorse?).
--
www.NetMax.tk