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RE: Tetanurae (Dinosauria: Theropoda).phylogeny

Metriacanthosauridae?  Yes!  Score one for following the rules.

Mickey Mortimer

> Date: Thu, 17 May 2012 08:53:44 -0700
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Tetanurae (Dinosauria: Theropoda).phylogeny
> From: Ben Creisler
> bcreisler@gmail.com
> A paper in the new issue of Journal of Systematic Palaeontology:
> Matthew T. Carrano, Roger B. J. Benson & Scott D. Sampson (2012)
> The phylogeny of Tetanurae (Dinosauria: Theropoda).
> Journal of Systematic Palaeontology 10(2): 211-300
> DOI:10.1080/14772019.2011.630927
> http://www.tandfonline.com/doi/abs/10.1080/14772019.2011.630927
> Abstract
> Tetanuran theropods represent the majority of Mesozoic predatory
> dinosaur diversity and the lineage leading to extant Aves. Thus their
> history is relevant to understanding the evolution of dinosaur
> diversity, Mesozoic terrestrial ecosystems, and modern birds.
> Previously, the fragmentary and poorly sampled fossil record of basal
> (non-coelurosaur) tetanurans led to uncertainties regarding their
> basic interrelationships. This in turn prevented determining the
> relationships of many incompletely known taxa that nonetheless
> document a global radiation spanning more than 120 million years. We
> undertook an exhaustive examination of all basal tetanurans and all
> existing character data, taking advantage of recent discoveries and
> adding new morphological, temporal and geographic data. Our cladistic
> analysis of 61 taxa achieved significantly improved phylogenetic
> resolution. These results position several ‘stem’ taxa basal to a
> succession of monophyletic clades (Megalosauroidea, Allosauroidea and
> Coelurosauria). Megalosauroids include nearly 20 taxa arrayed amongst
> a basalmost clade (Piatnitzkysauridae, fam. nov.) and the sister taxa
> Spinosauridae and Megalosauridae; the latter includes two subfamilies,
> Megalosaurinae and Afrovenatorinae subfam. nov. Allosauroidea contains
> a diverse Metriacanthosauridae (= Sinraptoridae), Neovenatoridae,
> Carcharodontosauridae and a reduced Allosauridae. Finally, we assessed
> more than 40 fragmentary forms and hundreds of additional reported
> tetanuran occurrences. Tetanuran evolution was characterized by
> repeated acquisitions of giant body size and at least two general
> skull forms, but few variations in locomotor morphology. Despite
> parallel diversification of multiple lineages, there is evidence for a
> succession of ‘dominant’ clades. Tetanurae first appeared by the Early
> Jurassic and was globally distributed by the Middle Jurassic. Several
> major clades appeared prior to the breakup of Pangaea; as such their
> absence in specific regions, and at later times, must be due to poor
> sampling, dispersal failure and/or regional extinction. Finally, we
> outline a general perspective on Mesozoic terrestrial biogeography
> that should apply to most clades that appeared before the Late
> Jurassic.