new paper on three African abelisauroids, 2

[Jose Ignacio Ruiz-Omeñaca <jigruiz@unizar.es>]

Some of the new  African abelisauroids were cited by:

SERENO, P. C., CONRAD, J. & WILSON, J. 2002. ABELISAURID THEROPODS FROM AFRICA: 
PHYLOGENETIC AND BIOGEOGRAPHIC IMPLICATIONS. Journal of Vertebrate 
Paleontology, 22(supplement to 3), 106A

Exploration of Lower and Upper Cretaceous outcrops in Niger has resulted in the 
discovery of abelisaurid fossils that impact on our understanding of 
dinosaurian biogeography during the Cretaceous.

The first abelisaurid, discovered in the Tiouraren Formation (Neocomian) in 
association with the sauropod Jobaria, constitutes the oldest material known 
for this clade. It includes an articulated presacral series from an individual 
that would have measured approximately three meters in length. Abelisaurid 
features include hypertrophied epipophyses, a strong interzygapophyseal lamina, 
and paired pneumatic openings on the centra.

The second abelisaurid, discovered in the Echkar Formation (Cenomanian), 
includes a well preserved, hornless cranium that shows an unusual series of 
pits on the dorsal skull roof. The new material is studied in the light of a 
phylogenetic analysis and clearly draws into question recent biogeographic 
scenarios that enlist the supposed absence of African abelisaurids to suggest 
the early separation and isolation of Africa from other Gondwanan landmasses.


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Jose Ignacio Ruiz-Omeñaca
Departamento de Ciencias de la Tierra
Area de Paleontologia
Universidad de Zaragoza
E-50009 ZARAGOZA, SPAIN

tel: (+34) 976 761000 ext. 3160
fax: (+34) 976 761106
e-mail: jigruiz@unizar.es
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