In press - Dentition of Amygdalodon

[Jocelyn Falconnet <j.falconnet@gmail.com>]

Carballidoa J.L. & Pol D. In press. The dentition of 
Amygdalodon patagonicus (Dinosauria: Sauropoda) and the dental evolution 
in basal sauropods. Comptes Rendus Palevol.
Received 2 April 2009; 
accepted 9 November 2009. 
Available online 1 April 2010.
doi:10.1016/j.crpv.2010.01.003
Amygdalodon patagonicus is the oldest record of Sauropoda from South 
America and is known from several teeth and fragmentary postcranial 
remains. Here we describe in detail its dental morphology, characterized 
by the presence of broad spatulated teeth (with low SI values) and the 
absence of denticles in their crowns. The enamel bears a particular 
wrinkling pattern composed only of apicobasally-aligned pits, which are 
frequently joined to each other by a continuous sulcus. Some worn teeth 
have large wear-facets that extend over only one of the crown's edges. 
This unique combination of characters provides a proper diagnosis for 
Amygdalodon. Despite the fragmentary available material, Amygdalodon is 
here interpreted as a non-eusauropod sauropod based on the results of a 
phylogenetic analysis. The presence of derived dental characters in 
Amygdalodon, such as the presence of tooth-tooth occlusion, shows 
several features previously thought to diagnose Eusauropoda or 
Gravisauria appeared earlier during the early evolution of sauropods.

--
Jocelyn Falconnet