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Date: Wed, 4 Sep 1996 21:14:25 -0400 (EDT)
From: T. Mike Keesey <firstname.lastname@example.org>
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There's something bothering me about this little predator.
Okay, there are two species - S. kayentakatae and S. rhodesiensis. The
former has paired crests, the latter doesn't. Other members of its family
(Coelophysidae) include Coelophysis (non-crested and small), Liliensternus
(large, crested?), and Dilophosaurus (large and crested).
It seems like Syntarsus is a paraphyletic species, with S. kayentakatae
closer to Dilophosaurus than to S. rhodesiensis! Is this the case?
Possibly I'm missing something. Did the common ancestor of the
Syntarsus and Dilophosaurus have crests, and then S. rhodesiensis lost
them? Or are the crests a case of convergent evolution?
These two ideas seem less likely to me. Also, someone has recently
suggested to me that Syntarsus was *polyphyletic*, with S. kayentakatae
closer to Dilophosaurus than Liliensternus is to Dilophosaurus
(Liliensternus being closer to these two than S. rhodesiensis).
What's the story here? If it is para/polyphyletic, what happens to the
name? If S. kayentakatae id the type species, I guess S. rhodesiensis
could be sunk into Coelophysis. Otherwise, wouldn't a new name be needed
for S. kayentakatae?
-T. Mike Keesey
Author of the
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