Nouvelle espèce d'Araripesuchus

Posté par Markvantomme il y a 18 ans

Turner, A.H. 2006. Osteology and phylogeny of a new species of Araripesuchus (Crocodyliformes: Mesoeucrocodylia) from the Late Cretaceous of Madagascar. Historical Biology 18(3):255-369


ABSTRACT: A new species of Araripesuchus present in the Maevarano Formation of Madagascar is described. The taxon is known from at least five individuals, including a nearly complete animal, three partial skulls and associated post-cranial remains, as well as disarticulated post-cranial elements. This large sample, coupled with CT-scans, allows a detailed description of its morphology. The new form shares a number of derived characters with Araripesuchus gomesii and Araripesuchus patagonicus, but is distinguished from them by the presence of four autapomorphies. Additionally, the new form lacks a number of derived features present
in A. gomesii and A. patagonicus.Phylogenetic relationships of Araripesuchus are evaluated using a parsimony analysis including 29 mesoeucrocodylian taxa. In all of the most
parsimonious trees the new taxon is recovered as sister group to A. gomesii+A. patagonicus. Araripesuchus is diagnosed by five unambiguous synapomorphies and forms a clade with the Malagasy crocodyliform Mahajangasuchus insignis and peirosaurids. This group is depicted as
more closely related to neosuchians than to notosuchians. When Araripesuchus wegeneri is included in the analysis, it is recovered as a member of the Araripesuchus clade. Although, its position in the clade is unresolved and character support is weak, this finding supports A. wegeneri as a valid species of Araripesuchus.


http://rapidshare.de/files/33354696/Turner_2006.rar