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[dinosaur] Megaraptor and Australoraptor manual anatomy + new Valdosaurus specimen (free pdfs)

Ben Creisler

In open access, a new memoir from the Museum Victoria in Australia in honor of Thomas Rich:


Dinosaur articles:

Fernando E. Novas, Alexis M. Aranciaga Rolando and Federico L. Agnolín (2016)
Phylogenetic relationships of the Cretaceous Gondwanan theropods Megaraptor and Australovenator: the evidence afforded by their manual anatomy.
Memoirs of Museum Victoria 74: 49–61



General comparisons of the manual elements of megaraptorid theropods are conducted with the aim to enlarge the morphological dataset of phylogenetically useful features within Tetanurae. Distinctive features of Megaraptor are concentrated along the medial side of the manus, with metacarpal I and its corresponding digit being considerably elongated. Manual ungual of digit I is characteristically enlarged in megaraptorids, but it is also transversely compressed resulting in a sharp ventral edge. We recognize two derived characters shared by megaraptorans and coelurosaurs (i.e., proximal end of metacarpal I without a deep and wide groove continuous with the semilunar carpal, and metacarpals I and II long and slender), and one derived trait similar to derived tyrannosauroids (i.e., metacarpal III length <0.75 length of metacarpal II). However, after comparing carpal, metacarpal and phalangeal morphologies, it becomes evident that megaraptorids retained most of the manual features present in Allosaurus. Moreover, Megaraptor and Australovenator are devoid of several manual features that the basal tyrannosauroid Guanlong shares with more derived coelurosaurs (e.g., Deinonychus), thus countering our own previous hypothesis that Megaraptora is well nested within Tyrannosauroidea.


Paul M. Barrett (2016)
A new specimen of Valdosaurus canaliculatus (Ornithopoda: Dryosauridae) from the Lower Cretaceous of the Isle of Wight, England.
Memoirs of Museum Victoria 74: 29-48 



The anatomy of Valdosaurus canaliculatus is incompletely known and until recently was based exclusively upon the holotype femora. Additional discoveries from the Wessex Formation (Barremian) of the Isle of Wight during the past decade have considerably expanded the amount of material available and offered insights into the morphology of the vertebral column and pelvis. However, all of these specimens consist primarily of hind limb material. Here, I describe a newly discovered individual of this taxon, the most complete yet found, which was found in articulation and includes a partial dorsal series, an almost complete tail, pelvic material, and both hind limbs. Although the specimen is partially crushed it offers new information on the anatomy of Valdosaurus, facilitating comparisons with other dryosaurid taxa.


Anthony J. Martin (2016)
A close look at Victoria's first known dinosaur tracks.
Memoirs of Museum Victoria 74: 63-71 



Lower Cretaceous (Aptian-Albian) rocks of Victoria, Australia are well known for their dinosaur body fossils, but not so much for their trace fossils. For example, the first known dinosaur track from the Eumeralla Formation (Albian) of Knowledge Creek, Victoria, was not discovered until 1980. This specimen, along with two more Eumeralla tracks found at Skenes Creek in 1989, constituted all of the dinosaur tracks recognised in Lower Cretaceous strata of southern Australia until the late 2000s. Unfortunately, none of these first-known dinosaur tracks of Victoria were properly described and diagnosed. Hence, the main purpose of this study is to document these trace fossils more thoroughly. Remarkably, the Knowledge Creek and one of the Skenes Creek tracks are nearly identical in size and form; both tracks are attributed to small ornithopods. Although poorly expressed, the second probable track from Skenes Creek provides a search image for less obvious dinosaur tracks in Lower Cretaceous strata of Victoria. The Skenes Creek tracks were also likely from the same trackway, and thus may represent the first discovered dinosaur trackway from Victoria. These tracks are the first confirmed ornithopod tracks for Victoria, augmenting abundant body fossil evidence of small ornithopods (‘hypsilophodontids’) in formerly polar environments during the Early Cretaceous.