Late Cretaceous Peruvian eggshells and their relationships with Laurasian and eastern Gondwanian material

Abstract

The eggshell material from some Late Cretaceous Peruvian sites is reevaluated in light of the results ofeggshell research in the last years. As a preliminary step, a new oospecies is first described from the Aix Basin (France): Megaloolithus pseudomamillare. The eggshells from the Bagua Basin Peru are divided into six types [1, Dinosauroid spherulitic type, Tubospherulitic morphotype and Angusticanaliculate pore system (M. pseudomamillare); 2, Dinosauroid spherulitic, undetermined morphotype; 3, Ornithoid type, Ratite morphotype, Angusticanaliculate; 4, Ornithoid type, Ratite morphotype; 5, Ornithoid type, Ratite morphotype or dinosauroid type, Angustispherulitic morphotype; 6, ? Geckonoid type]. Because of presumable loss of the main part of the material, it was not possible to make additional studies on the eggshells from Laguna Umayo. We can only assess that the tuberculate fragments described by Kerourio & Sigé (1984) belong to Megaloolithus, and that the type 2 of this locality could be the same as the type 5 of the Bagua basin. The family Megaloolithidae is thus recorded in Europe, India and South America; it seems that the same oospecies exists in these three areas, in Late Cretaceous deposits. The available biochronological data discussed here support the tentative correlation of the Umayo Formation with the Fundo et Triunfo Formation.