Re: The timing of stegosaur extinction

[David Marjanovic <david.marjanovic@gmx.at>]

Since it looks like nobody more knowledgeable than I got this mail correctly 
displayed (it has no line breaks), I'll try...

----- Original Message -----
From: "Joe Cantrell" <joecntrll@yahoo.com>
To: <dinosaur@usc.edu>
Sent: Monday, February 14, 2005 6:28 PM
Subject: The timing of stegosaur extinction

> When did the last stegosaurs disappear in North America, South America, 
> Africa Europe and other regions?
> Joe

Good question. Usually stegosaurs are rare, and because most, uh, 
vertebrates are rare in general, we can't automatically assume that the 
youngest fossil coincides with the extinction of the group. -- If I recall 
correctly, stegosaurs are known from:

NA: Late Jurassic only, including the last stage of that epoch.
SA: Early Cretaceous only. (The one fossil is still unnamed.)
Africa: Late Jurassic only.
Europe: Middle Jurassic to Early Cretaceous.
Asia: Middle Jurassic to Early Cretaceous.

Probably this means that Stegosauria as a group died out around the end of 
the Early Cretaceous. Surprises can't be excluded.

You might have heard of *Dravidosaurus*, which was described as a Late 
Cretaceous stegosaur from India... this has turned out to be a badly 
preserved bone of a plesiosaur.