RE: Giant Paleozoic arthropods; Also, SVP field trips

["Thomas R. Holtz, Jr." <th81@umail.umd.edu>]

At 03:22 PM 6/29/99 +1000, Adam Yates wrote:

>>Well, the sea scorpions (which actually were probably fresh water
>>animals,
>>and could move on land) got over six feet!.
>
>The aquatic Sea Scorpions were not true scorpions, they were chelicerates
>whose closest modern relatives are the horseshoe crabs.

Actually, although eurypterids ("sea scorpions") are not true scorpions, the
monophyly of Merostomata (eruypterids + xiphosurans ("horseshoe crabs")) is
suspect.  For example, in Willis et al., eurypterids are closer to arachnids
(including scorpions) than are modern limulids (modern horseshoe crabs),
while other Paleozoic "xiphosurans" are outside that clade.  Selden & Dunlop
(in the same volume) also place eurypterids as closer to arachnids than to a
(there monophyletic) Xiphosura.

Willis, M. A., D. E. G. Briggs, R. A. Fortey, M. Wilkinson & P. H. A.
Sneath.  1998 An arthropod phylogeny based on fossil and recent taxa.  In
Edgecombe, G. D. (ed.) Arthropod Fossils & Phylogeny.  Columbia Univ. Press.
pp. 33-105.

Of course, I want to point out that Eurptyerida was long extinct before the
dinosaurs (the subject of this list) were ever around!

So, in order to help justify this message on the dinosaur list, I just
received my copy of the second circular for the 1999 Society of Vertebrate
Paleontology meeting.  It includes the field trips, four of which are
directly tied in to dinosaur studies.  These are:

Upper Triassic Stratigraphy and Paleontology of the Eagle Basin, Colorado

The Can~on City Dinosaurs Sites of Marsh and Cope; and the Indian Springs
Trace Site

In the Steps of the Dinosaurs: A Tour of dinosaur Ridge

Tracing the Cretaceous-Tertiary Faunal Transition in a Catastrophically
Urbanized Landscape

For more info, check out the SVP website:
http://www.museum.state.il.us/svp//meetings/2ndCirc.html

If you've never been out in the western U.S. (or if you have and you've
never seen fossils in situ), and you are going to the meeting, I'd recommend
you think about taking one of these trips.

                        Thomas R. Holtz, Jr.
                        Vertebrate Paleontologist
Deptartment of Geology                  Director, Earth, Life & Time Program
University of Maryland                  College Park Scholars
College Park, MD  20742       
Webpage: http://www.geol.umd.edu        Phone:301-405-4084
Email:tholtz@geol.umd.edu               Fax:  301-314-9661