YATES ON SELLOSAURUS

[darren.naish@port.ac.uk]

Dorsal frills and multiple babies in pterosaurs, scavenging 
tyrannosaurs and incredibly young dicynodonts aside... the 
following is out...

Yates, A. M. 2003. The species taxonomy of the 
sauropodomorph dinosaurs from the Lowenstein Formation 
(Norian, Late Triassic) of Germany. _Palaeontology_ 46, 
317-337.

This is the published version of Adam's presentation given 
at SVPCA 2002. _Sellosaurus_ is found to encompass two 
distinct taxa: _Efraasia minor_ [_Teratosaurus (?) minor_ 
Huene, 1908 is the oldest name given to a representative of 
this taxon - _S. fraasi_ and _Efraasia diagnosticus_ are 
among the junior synonyms], diagnosed by 'an 
interbasipterygoid web with a central tubercle and a 
hypertrophied semilunate-shaped pubic tubercle projecting 
laterally from the proximal pubis' (p. 328), and 
_Plateosaurus gracilis_. The latter is shown to be extremely 
similar to _P. engelhardti_ and, while the two 
_Plateosaurus_ sp. differ in neural spine proportions and the 
size of the brevis shelf, Adam notes that _P. gracilis_ might 
be a metataxon. _P. gracilis_ is smaller (4.5 to perhaps 6m) 
than _P. engelhardti_ (to 9m).

Skeletal reconstructions of the three taxa are provided: 
superficially at least, _E. minor_ is a more gracile, longer-
legged, shorter-skulled and rather more thecodontosaur-like 
animal than _Plateosaurus_. A specimen-based parsimony 
analysis finds _Saturnalia_ and _Thecodontosaurus_ to be 
basal to a _Plateosaurus_-_Efraasia_ clade. 

There is tons of character data in here and it is required 
reading for anyone into sauropodomorph 
diversity/systematics/phylogeny.

-- 
Darren Naish
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL

email: darren.naish@port.ac.uk
tel: 023 92846045