PARATAXONOMIC REVIEW OF THE UPPER CRETACEOUS DINOSAUR EGGSHELLS BELONGING TO THE OOFAMILY MEGALOOLITHIDAE FROM INDIA AND ARGENTINA

FERNÁNDEZ, MARIELA S.; KHOSLA, ASHU

Cordoba

Jornada; REUNIÓN DE COMUNICACIONES DE LA ASOCIACIÓN PALEONTOLÓGICA ARGENTINA; 2013

Asociación Paleontológica Argentina

The oofamily Megaloolithidae is one of the most diverse oofamilies in terms of oospecies. Dinosaur eggs and eggshell fragments have attained importance during the last three decades and have been diversely recorded from various localities worldwide. In Argentina, five type of megaloolithid eggshells were described, two of these were assigned to the oospecies Patagoolithus salitralensis and Megaloolithus patagonicus were described belonging to the oofamily Megaloolithidae. Other 3 types were described from Río Negro, which have not been assigned to any oospecies till date. In India, 15 types of eggshell oospecies were described. nevertheless, no sauropod and theropod embryos have yet been found in direct association with such eggs and the assignment of the eggshells to the oofamiliy Megaloolithidae are based on the skeletal material in the associated horizons and on the structure of nests. But the discovery of embryonic remains in some of the Argentinan eggshells indicates that some of the Megaloolithid eggs belong to sauropod dinosaurs. We synonymize Megaloolithus jabalpurensis with Megaloolithus matleyi and Megaloolithus patagonicus, and Megaloolithus cylindricus with Type 1d and Megaloolithus megadermus with Type 1e. Megaloolithus megadermus probably is related with Paquiloolithus rionegrinus Simón. We study the microstructure of several oospecies from the Oofamily Megaloolithidae and we found that Megaloolithus baghensis, M. dhaliyaensis, M. padiyalendis, M. mohabeyi and Patagoolithus salitralensis have partially fused shell units, as occurs in prolatospherulitic morphotype, so we propose a new oofamily with a dinosauroid-spherulitic type, a prolatospherulithic morphotype and a tubocanaliculate pore system which includes all the Megaloolithus oospecies cited before.