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New Triassic Papers in the Festschift in Honor of Dr. Wann Langston Jr.

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Back in very early 2010 Dr. Ernie Lundelius was honored with a festschift volume.  When I congratulated him on it he lamented that his close friend and colleague Dr. Wann Langston Jr., still did not have a festschift in his honor.  Ernie said they had tried to get one going a few times but nothing had ever come of it. I agreed to help to start another one and after several trials am proud to announce that the first online papers are now available from the Earth and Environmental Transactions of the Royal Society of Edinburgh. The final print volume will be out a bit later.  Unfortunately Dr. Langston passed away earlier this year and did not get to see the completed volume; however he did get to see a compilation of the abstracts.

Dr. Langston was Charles L. Camp's graduate student at the University of California at Berkeley and althogh his dissertation was on Permian vertebrates of North America, one of his firs publications was a description of a new phytosaur from the Upper Triassic of Texas.  Thus it is fitting that there are a few Triassic papers in his festschrift volume.  Two, which I was involved with, are up currently: I'll post the rest when they come online.

Parker, W. G. 2013. Redescription and taxonomic status of specimens of Episcoposaurus and Typothorax, the earliest known aetosaurs (Archosauria: Suchia) from the Upper Triassic of western North America, and the problem of proxy “holotypes”. Earth and Environmental Transactions of the Royal Society of Edinburgh First View Article. DOI: http://dx.doi.org/10.1017/S1755691013000212

Abstract - Historic type and referred material of the aetosaurian taxa Typothorax coccinarum, Episcoposaurus horridus and Episcoposaurus haplocerus are redescribed and the non-aetosaurian material identified and removed, a task previously considered “hopeless”. Reexamination of the original material reveals that the holotypes of E. haplocerus and probably T. coccinarum are not diagnosable at the species level and therefore are nomena dubia. The next available names for material referred to these taxa are Desmatosuchus spurensis and E. horridus respectively, although it may be more desirable for reasons of taxonomic stability to attempt to petition for a neotype in the latter case. The redescription of historical specimens is necessary to determine their nomenclatural validity. The use of referred specimens as proxy “type” specimens is problematic, as these referrals were originally made not on the basis of apomorphies, but rather on biostratigraphic and/or geographical assumptions which are inherently circular and cannot be unambiguously supported.

Martz, J. W., Mueller, B., Nesbitt, S. J., Stocker, M. R., Parker, W. G., Atanassov, M., Fraser, N., Weinbaum, J., and J. R. Lehane. 2013. A taxonomic and biostratigraphic re-evaluation of the Post Quarry vertebrate assemblage from the Cooper Canyon Formation (Dockum Group, Upper Triassic) of southern Garza County, western Texas. Earth and Environmental Transactions of the Royal Society of Edinburgh First View Article. DOI: http://dx.doi.org/10.1017/S1755691013000376

Abstract - The Post Quarry, within the lower part of the type section of the Upper Triassic Cooper Canyon Formation in southern Garza County, western Texas, contains a remarkably diverse vertebrate assemblage. The Post Quarry has produced: the small temnospondyl Rileymillerus cosgriffi; the metoposaurid Apachesaurus gregorii; possible dicynodonts and eucynodonts; a clevosaurid sphenodontian; non-archosauriform archosauromorphs (Trilophosaurus dornorum, simiosaurians, and possibly Malerisaurus); the phytosaur Leptosuchus; several aetosaurs (Calyptosuchus wellesi, Typothorax coccinarum, Paratypothorax, and Desmatosuchus smalli); the poposauroid Shuvosaurus inexpectatus (“Chatterjeea elegans”); the rauisuchid Postosuchus kirkpatricki; an early crocodylomorph; several dinosauromorphs (the lagerpetid Dromomeron gregorii, the silesaurid Technosaurus smalli, a herrerasaurid, and an early neotheropod); and several enigmatic small diapsids. Revised lithostratigraphic correlations of the lower Cooper Canyon Formation with the Tecovas Formation, the occurrence of Leptosuchus, and the overall composition of the assemblage indicate that the Post Quarry falls within the Adamanian biozone, and not the Revueltian biozone. Stratigraphic subdivision of the Adamanian biozone may be possible, and the Post Quarry may be correlative with the upper part of the Adamanian biozone in Arizona. The age of the Post Quarry assemblage is possibly late Lacian or earliest Alaunian (late early Norian or earliest middle Norian), between 220 and 215 Ma.








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