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Re: ARCHAEOPTERYX STAGE



At 08:33 AM 11/20/96 +1030, you wrote:
>Jeff Poling wrote:
>
>> None of the references I have, including _The Dinosauria_, lists the
>> era/stage that Archaeopteryx is associated with.  They merely say "Late
>> Jurassic."  Anybody happen to know the era/stage Archie is associated with?
>
>Yeah, _Archaeopteryx lithographica_ is Tithonian. This is the uppermost Stage
>of the Jurassic (follows Oxfordian and Kimmeridgian): some European workers
>consider it to consist of Portlandian and Purbeckian. Remains previously
>allocated to _Archaeopteryx_ (perhaps they should have been Archaeopterygidae
>sp. or cf. _Archaeopteryx_) from eastern Europe are from the earliest Stage of
>the Lower Cretaceous (Berriasian), but I think they're now thought to be
>pterosaurian. I wouldn't put money on the exact age of _A. bavarica_.
>
>[There seems to be a difference of opinion on the age of _Archaeopteryx_
>here.  Does anyone have a definitive reference? - Chris]

Double-checking the 1994 Wellnhofer paper (the Solnhofen-Aktien-Verein
specimen, so-called A. bavarica) is stratigraphically the highest of the
specimens, and is in the Malm Zeta 2b horizon, lowermost lower Tithonian
(unteres Untertithon).  All the other specimens are stratigraphically below.
If I can find it (in my "free" (HAH) time), I will see if I can locate the
age of the Sieben-Lumpen-Schicht and the Trennende Krumme Lage.  The Maxberg
is in between A. bavarica and the S-L-S; the London specimen (the lowest) is
in between the S-L-S and the T K L.  Don't have the exact horizons for the
other specimens within the Solnhofen sequence.

P.S., to add a comment that some might get (and that I picked up this weekend):

"It's a Mega..., Mega..., Mega..."
("Sounds big.")
"MEGATHERIUM!"

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661

"To trace that life in its manifold changes through past ages to the present
is a ... difficult task, but one from which modern science does not shrink.
In this wide field, every earnest effort will meet with some degree of
success; every year will add new and important facts; and every generation
will bring to light some law, in accordance with which ancient life has been
changed into life as we see it around us to-day."
        --O.C. Marsh, Vice Presidential Address, AAAS, August 30, 1877