Happy Halloween!

Happy Halloween Everyone! This year, I decided to carve my pumpkin as Smilosuchus. I got a lot of compliments from trick-or-treeters, although a lot thought it was a dinosaur. A few managed to guess it was a crocodile, which I figured was close enough for 8-year-olds. Did anyone else carve paleo-inspired pumpkins?

Alright, I'm off to Vegas. See you all at SVP!

SVP 71st Annual Meeting

The annual meeting of the Society of Vertebrate Paleontology is just one week away. Incorporated into the logo for this year's meeting is the Nevada state fossil, Shonisaurus popularis, a Late Triassic ichthyosaur, as well as the dinosaur track Eubrontes (the suit on the cards).

There will be no shortage of talks and posters on "forgotten archosaurs" at this years meeting. On Wednesday, there will be a handful of general archosaur talks in the morning and afternoon. Thursday talks will be sparse, but there will be dozens of good posters. All day Friday and Saturday morning are almost completely devoid of non-dinosaurian archosaur talks, but Saturday afternoon will bring us the croc talks. Not a bad way to end the meeting.

A message from the Student & Post-Doctoral Liaison Committee

As a member of the committee, I have a small request to ask of my lovely readers: PLEASE BRING LOTS OF REPRINTS! Each year, the S&PLC hosts the Student Roundtable Forum and Reprint Exchange. We rely entirely on generous donations from SVP members for reprints so, if you have a bunch of reprints sitting around your office and wouldn't mind contributing, please bring them to the meeting. You can bring them to the S&PLC table, where we will be selling raffle tickets and offering guidance to first time attendees. 

Each year, the student committee sells raffle tickets for a chance to win a free student membership or fabulous door prizes. Not a student? You can still buy a raffle ticket (or 20) and donate it to a student. Proceeds benefit the SVP Education and Research Fund. More info can be found at the annual meeting website.

The Sail-Backed Poposauroid - Ctenosauriscus

Butler RJ, Brusatte SL, Reich M, Nesbitt SJ, Schoch RR, et al. 2011. "The Sail-Backed Reptile Ctenosauriscus from the Latest Early Triassic of Germany and the Timing and Biogeography of the Early Archosaur Radiation." PLoS ONE 6(10): e25693. doi:10.1371/journal.pone.0025693


Abstract

Background
Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3–247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains.

Methodology/Principal Findings
We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the ‘sail’ of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation.

Conclusions/Significance
Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian–Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which appear to have been the first global radiation of archosaurs.

Rauisuchian Osteoderms

Scheyer, T. M. and J. B. Desojo. 2011. "Palaeohistology and external microanatomy of rauisuchian osteoderms (Archosauria: Pseudosuchia)." Palaeontology. DOI: 10.1111/j.1475-4983.2011.01098.x

Abstract

The presence of postcranial dermal armour is plesiomorphic for Archosauria. Here, we survey the external microanatomy and histology of postcranial osteoderms (i.e. dorsal paramedian and caudal osteoderms) of rauisuchians, a widely distributed assemblage of extinct predatory pseudosuchians from the Triassic. The osteoderms of eight rauisuchian taxa were found to be rather compact bones, which usually lack significant bone remodelling or large areas of cancellous bone. The presence of highly vascularized woven or fibrolamellar bone tissue deposited in the core areas indicates higher growth rates during earlier life stages, whereas a more compact parallel-fibred bone matrix indicates reduced growth rates in later development. This pattern of change corroborates earlier studies on long bone histology. With the exception of a bone tissue found in the sample of Batrachotomus kupferzellensis, which might be the result of metaplastic ossification, the general mode of skeletogenesis is comparable with intramembraneous ossification. The lack of cancellous bone tissue and remodelling processes associated with bone ornamentation, as well as the predominantly intramembraneous mode of ossification, indicates that rauisuchian osteoderm formation differs profoundly from that of the osteoderms of the only extant pseudosuchian lineage, the crocodylians.

Taxonomy of Diplocynodon and Tooth Wear in Caiman latirostris

Martin, Jeremy E. and Martin Gross. 2011. "Taxonomic clarification of Diplocynodon Pomel, 1847 (Crocodilia) from the Miocene of Styria, Austria" Neues Jahrbuch für Geologie und Paläontologie - Abhandlunge, 261:2 DOI: 10.1127/0077-7749/2011/0159

Abstract
A re-examination of the original type series of Prangner (1845) and Hofmann (1887a) of the primitive alligatoroids from the middle Miocene of Styria, led to a reappraisal of the taxonomy of the following species of Diplocynodon: D. steineri and D. styriacus. Of unsettled affinities, Enneodon ungeri was also re-examined. It is here demonstrated that it belongs to the same taxon of the specimens described by Hofmann (1887a). These taxa are in fact junior synonyms of the previously erected Enneodon ungeri. Moreover, comparison with other European alligatoroids reveals that the Austrian specimens described by Prangner (1845) and Hofmann (1887a) belong to the same genus: Diplocynodon Pomel, 1847. According to the rules of the International Commission on Zoological Nomenclature (ICZN), Diplocynodon has priority over Enneodon. Under the principle of priority, it is therefore proposed to rename all the Miocene remains of alligatoroids from Styria as Diplocynodon ungeri Prangner, 1845. Comparison of almost complete skulls from various Miocene contemporaneous localities reveals that there is no reason to erect another taxon for the French specimens of D. "styriacus" described in Ginsburg & Bulot (1997). However, these specimens need to be redefined as D. ungeri as well. D. ungeri was coded and included in a character matrix to cladistically test its affinities with other alligatoroids. A total of six species of Diplocynodon were analysed including: D. ratelii, D. hantoniensis, D. tormis, D. muelleri, D. darwini and D. ungeri. The results are consistent with previous studies and favour a monophyletic diplocynodontid clade. D. ungeri is the first species of the genus to be recognized from distant coeval European deposits, namely the Paris and the Pannonian Basins.

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Ősi, Attila and Paul M. Barrett. 2011. "Dental wear and oral food processing in Caiman latirostris: analogue for fossil crocodylians with crushing teeth" Neues Jahrbuch für Geologie und Paläontologie - Abhandlunge, 261:2 DOI: 10.1127/0077-7749/2011/0161

Abstract
Almost all of the 23 extant species of crocodylians are opportunistic predators that consume their food without extensive intraoral food processing. Posterior bulbous crushing teeth with heavy dental wear in two specimens of Caiman latirostris, however, indicate that oral food processing can be an important factor during feeding. Wear pattern analysis in two specimens of C. latirostris clearly indicates crushing of hard food items that produced large wear surfaces on tooth crowns in the posterior part of the tooth row. This type of wear suggests that the diet was predominantly composed of durable, hard-shelled prey (e.g.molluscs, crustaceans, turtles), a supposition confirmed by recent studies on the stomach contents of several C. latirostris specimens. The absence of similar wear patterns in other ontogenetically mature specimens of C. latirostris, however, indicates that specific, possibly regional differences in food resources might affect the degree and type of dental wear. The dental features we report in C. latirostris can provide an important extant analogue for fossil forms with similar dentitions (e.g. Bernissartia, Unasuchus and globidontan eusuchians).