[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Juvenile specimen of Yunnanosaurus from Early Jurassic of China

> Date: Thu, 29 Aug 2013 08:12:11 -0700
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Juvenile specimen of Yunnanosaurus from Early Jurassic of China
> Finally, ZMNH-M8739 constitutes a monophyletic group with Y. robustus
> (holotype), and Y. huangi is nesting this clade in the phylogenetic
> tree of the present analysis. Comparison of juvenile and adult
> specimen reveals distinctive growth changes of Y. robustus. This clade
> is positioned in an unnamed clade at a sister taxon of Sauropoda.
> Finally, some members of the so-called prosauropod dinosaurs
> constitute a monophyletic group in the present result.

To elaborate on this, in case anyone else is curious:

Included sauropodomorphs basal to the Prosauropoda/Sauropoda split include, in 
ascending order: Saturnalia (actually considered outside Sauropodomorpha sensu 
Sekiya et al, as sister taxon of the outgroup taxon Guaibasaurus), 
Thecodontosaurus, Efraasia, and Anchisaurus. 

The monophyletic Prosauropoda includes the still-unnamed "Gyposaurus" sinensis 
as the most basal member, followed by Sarahsaurus, Massospondylidae 
(Massospondylus & Adeopapposaurus), and Plateosauridae (Plateosaurus, 
Riojasaurus, Coloradisaurus & Lufengosaurus).

The sister group of Sauropoda referred to as an "unnamed clade" in the abstract 
(hasn't Yunnanosauridae been named already?) includes a monophyletic 
Yunnanosaurus, and a clade including Jingshanosaurus and Seitaad. 
 Plateosauravus is in an unresolved trichotomy with yunnanosaurids and 

The basalmost members of Sauropoda (sensu Sekiya et al) form a comb including 
Antetonitrus, Aardonyx, Blikanasaurus, Lessemsaurus, and Melanorosauridae 
(Camelotia & Melanorosaurus).  Lamplughsaura is also a basal sauropod and is 
found as the sister taxon of the gravisaurs.