Field of Science

I just gotta say this....

Unlike my colleague Jeff Martz I am not drinking myself into a stupor tonight because of some horrible singer, but reading through a few papers over the last few days has finally pushed me to the edge as well...and like Jeff I need to talk about this.

There are two errors, which should not be, that persistently show up in the Triassic literature. One is relatively minor but annoying, whereas the other is not only annoying but does have implications.

1) For the last 13 years Long and Murry (1995) has likely been the most cited paper for Late Triassic vertebrate paleontology. Prior to this Phillip Murry published quite a few papers dating back to the early 1980s on Triassic paleontology and Geology. His name, although uncommon, has only five letters in it. Why, with a simple name and numerous citations do many people continue to misspell his name (as Murray) in many papers? And why do the reviewers not catch this either? Again, nothing major but just annoying seeing it in paper after paper.

2) Having done my graduate work and published several papers concerning the aetosaur Desmatosuchus, I have noticed and continue to notice that despite being known by good material for over 80 years people continue to incorrectly assign material to this genus. Historically, any robust spiked aetosaur has been assigned to his taxon and that has caused much confusion; however, since 1985 the genus has been diagnosed using in part the ornamentation of its dermal osteoderms. Desmatosuchus is the only aetosaur genus that combines an ornamentation of randomly placed pits and grooves (with no radial patterning at all), a depressed anterior lamina (a smooth area of the osteoderm that underlies the preceding plate), and a centrally placed dorsal boss. This has been repeated numerous times in the literature yet I constantly come across material with a strong radial pattern being assigned to the genus. Last year a major Triassic exhibit opened in a major U. S. natural history museum. In this exhibit (which is for the most part very well done) Desmatosuchus is represented by an osteoderm, which has an extreme radial patterning, a posteriorly placed boss, and a raised anterior bar, the exact reverse of the diagnosis of Desmatosuchus.

When I was visiting museum collections on a very limited budget as a graduate student it was extremely frustrating to travel to institutions and then find out that all of the Desmatosuchus material was misidentified. It is even more frustrating to see this continuing, and yes it does have implications. Periodically you will see papers come out where comparisons with Desmatosuchus are being made, yet it quickly becomes apparent (at least to me) that the comparisons are based on a misidentified specimen. Desmatosuchus also possibly has some biostratigraphic significance, but again many voucher specimens for purported occurrences are based on misidentifications. Finally, a misidentification of material as Desmatosuchus eventually placed me in one of the most frustrating and unfortunate situations I have every found myself in in my entire life.

I do realize that misidentifications happen all the time with lots of fossils, however, it is unfortunate when it is done over and over again. Below are some representative plates and drawings of Desmatosuchus spurensis. The photographed material is MNA V9300. The drawings are from Long and Ballew (1985).

OK...rant over. Thanks for reading and please ID your Desmatosuchus material correctly.
Long, R. A., and K. L. Ballew. 1985. Aetosaur dermal armor from the Late Triassic of southwestern North America, with special reference to material from the Chinle Formation of Petrified Forest National Park. Museum of Northern Arizona Bulletin 54:45-68.

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