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Re: Cladistics and biology: Long(sidetrack)
>ok, so this isn't actually a dinosaur question, but....
> I'm rather curious of the modern Coelecanth-lungfish groups. How do
>group the Bicher (I have a small Ornate Bicher in a nocturnal set-up
>tank)(begins with a p-something), the Ropefish, Coelecanths, and Lungfishes.
> I'm aware of lungfish from Asia and Africa; Ropefish from Africa, and
>from Africa (the Rift Valley).
The Bichirs (note spelling) [Polypterus spp.] and Reedfish [Calamoichthys]
(which I presume is what you mean by Ropefish) were once thought to be
relatives of the lobe-finned fishes but this view has not been accepted for
a long time. They do not belong in the Sarcopterygii, the branch of the
bony fish line that includes coelacanths, lungfishes, lobefins and
tetrapods, but to the other line, the Actinopterygii, that includes the vast
majority of living fishes. Within the Actinops the bichirs are considered
to be the only living representatives of the earliest line in the group, the
palaeoniscoid fishes. In a modern classification (from Long, The Rise of
Fishes) they form the Order Polypteriformes in the Infraclass Chondrostei;
other living chondrosteans are the sturgeons and paddlefishes.
The true lungfishes include the African Protopterus, the Australian
Neoceratodus and the South American Lepidosiren. Long puts them in the
Subclass Dipnoi; the coelacanth goes in the other sarcopterygian subclass,
the Crossopterygii (which, by this classification, also includes all
tetrapods), but in a separate order, Actinistia.
I recommend Long's book as a very good intro for a non-fish person like me,
though it's a bit heavy on the technical details.
Ronald I. Orenstein Phone: (905) 820-7886 (home)
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