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Re: Condylarths (TINGAMARRA REVISITED)



David,
Well I'll agree that Ungulata is probably polyphyletic. But who has put zhelestids outside of Placentalia?
I am rather skeptical of this, and I don't know how you can say there are no crown-group placentals known from the Cretaceous. Are you also saying that Kennalestids, Cimolestids, and Leptictids are are not crown-group placentals??
-------Ken
*******************************************************
From: "David Marjanovic" <david.marjanovic@gmx.at>
Reply-To: david.marjanovic@gmx.at
To: "The Dinosaur Mailing List" <dinosaur@usc.edu>
Subject: Re: Condylarths (TINGAMARRA REVISITED)
Date: Tue, 22 May 2001 23:50:42 +0200

> I can't recall the stratigraphical details, but _Protungulatum donnae_ is
> earliest Paleocene. The material comes from the Bug Creek Anthills of
> Montana.


Ah, the famous Bug Creek... I see. Thanks! :-) So this confirms that there
is no crown-group placental known from the Cretaceous.

> Some workers have followed Van Valen in regarding _Protungulatum_ as an
> arctocyonid, at least provisionally (e.g. Lillegraven, 1998). Another
> approach is to regard this genus as an ungulate (or ungulatomorph)
incertae
> sedis (e.g. McKenna and Bell, 1997; Archibald, 1998).
>
> In a recent study of the "condylarths", Muizon and Cifelli (2000) placed
> _Protungulatum_ close to the base of the Ungulatomorpha, but more derived
> than the zhelestids (the most primitive known ungulatomorphs).


Well, the zhelestids are now being put outside Placentalia, and the
geneticists say that Ungulata, -omorpha, -... are terribly polyphyletic
anyway...

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