Systematics of Indian Upper Cretaceous dinosaur and chelonian eggshells

ABSTRACT

A large number of dinosaur nesting sites have been documented from the Upper Cretaceous (Maestrichtian) Lameta Formation of India. A remarkable diversity is noticeable in the eggshells. Based on the general morphology and the histostructure, they are parataxonomically assignable to oofamily Megaloolithidae (Tubospherulithic morphotype) and Elongatoolithidae (Ratite morphotype). Ten new oospecies of these eggshells are described in the present paper. Of these, the eight oospecies are assignable to oogenus Megaloolithus, one to the newly established oogenus Ellipsoolithus and the remaining one has been categorised as Incertae sedis. In addition, associated chelonian eggshells are also described.

The Indian Upper Cretaceous dinosaur fauna is dominated by the titanosaurids (sauropods), and reports of theropods (megalosaurid and tyrannosaurid) and ornithopods are. The eggs, whose shells are here attributed to a number of oospecies, must have had their parentship amongst these known dinosaurs. Many eggs are unhatched and completely preserved and may have a significant bearing on the extinction of dinosaurs. The majority of the eggshells are observed to be normal, except a few which exhibit pathologic features. The presence of numerous nesting sites and the skeletal remains of the dinosaurs, suggest that the palaeoenvironment in the Late Cretaceous of India provided an ideal habitat for titanosaurid and megalosaurid dinosaurs.