A GIANT ABELISAURID THEROPOD FROM THE LATEST CRETACEOUS OF NORTHERN TURKANA, KENYA SERTICH, Joseph, Denver Museum of Nature & Science, Denver, CO, United States, 80205; O'CONNOR, Patrick, Ohio University, Athens, OH, United States; SEIFFERT, Erik, Stony Brook University, Stony Brook, NY, United States; MANTHI, Fredrick Kyalo, National Museums of Kenya, Nairobi, Kenya The African fossil record of Cretaceous non-marine vertebrates has expanded significantly over the past two decades. However, these discoveries have been limited to Lower and middle Cretaceous horizons with a conspicuous absence of fossils from the latest Cretaceous, an interval of prolonged African isolation. Recently recovered vertebrate fossils from the Lapurr Mountains of northwestern Turkana, Kenya, comprise the first definitive non-marine fauna from this critical terminal Cretaceous interval. This diverse fauna from the Lapurr sandstone (“Turkana Grits”) has been dated to the Maastrichtian and includes crocodyliforms, pterosaurs, and dinosaurs. Though fragmentary, the dinosaur record includes at least two iguanodontian ornithopods, three macronarian sauropods, and two large theropods. Here we report on one of these theropods, a new abelisaurid that significantly expands the upper limits of body size in ceratosaurians and represents the youngest diagnostic dinosaur material yet reported from the Afro-Arabian continent. The new taxon is known from multiple isolated specimens including portions of the skull, axial column, and appendicular skeleton. Referral of unassociated remains to a single taxon is based on morphological consistency and on the recovery of specimens from a narrow stratigraphic and geographic area. A comprehensive phylogenetic analysis substantiates referral of the new Kenyan taxon to Abelisauridae based, among other features, on the presence of a tall, rugose premaxilla, an anteroventrally inclined posterior border of the postorbital, and a prominent dorsal projection of the parietals and supraoccipital. An associated partial skull is strongly coossified, with a thickened but weakly sculptured skull roof. Unlike many other abelisaurids, no prominent cranial ornamentation is evident. As in other ceratosaurians, the astragalocalcaneum is completely coossified and displays a prominent transverse sulcus on the anteroventral surface. Like other abelisaurids, the ascending process is low and subrectangular, separated from the anterior surface of the astragalus by a distinct fossa. Comparison of preserved elements with those of other, more complete abelisaurids indicates that the new taxon likely exceeded 11-12 meters in length. Furthermore, the presence of a large- bodied abelisaurid in the Kenyan fauna parallels many other Late Cretaceous Gondwanan faunas, reflecting global early Late Cretaceous turnover from allosauroid and spinosaurid dominated ecosystems."

There's a new giant Thropods, 11-12 meters long!