Bioerosion traces on the Campanian turtle remains: New data from the lagoonal deposits of the Quseir Formation, Kharga Oasis, Egypt

Abstract

The uppermost part of the Campanian Quseir Formation of Kharga Oasis, Egypt, contains a concentration of turtle skeletal remains in a lagoon setting. They appear as three successive horizons (I‒III), alternated between the variegated shales and the glauconitic mudstones and conglomeratic layers within the Hindaw Member. However, bones recovered in horizon III present a higher preservation potential than the others. Therein, turtle remains are represented by mostly complete shells, partial shells and many scattered and weathered shell fragments. The studied turtles lived in small ponds and marshes and were deposited as autochthonous to parautochthonous relics. Their bones display significant