A reevaluation of Sigilmassasaurus brevicollis (Dinosauria) from the Cretaceous of Morocco
1. Bradley McFeeters (a)
2. Michael J. Ryan (a)
3. Sanja Hinic-Frlog (b)
4. Claudia Schröder-Adams (a)
a. Dept. of Earth Sciences, Carleton University, Ottawa, ON K1S 5B6, Canada.
b. Dept. of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada.
The original hypodigm of the controversial mid-Cretaceous Moroccan dinosaur Sigilmassasaurus brevicollis is redescribed, and the diagnosis of the taxon is revised. Unambiguously referred material is restricted to cervical and anterior dorsal vertebrae sharing apomorphies with the holotype. A newly recognized diagnostic character of Sigilmassasaurus is the absence of anterior and posterior interzygapophyseal laminae of the neural arch, so that the neural spine directly meets the dorsal margin of the neural canal. A phylogenetic analysis supports the inclusion of Sigilmassasaurus in Tetanurae but not in Carcharodontosauridae. Sigilmassasaurus is distinct from all other theropods known from comparable material and is thus retained as a valid taxon.