Exceptionally well-preserved crocodilian coprolites from the Late Eocene of Northern Vietnam: Ichnology and paleoecological significance

This study examines 55 coprolites from the Na Duong Basin to reconstruct the paleoenvironment. Coproecology sheds light on understanding the complex prey-predator relationships, trophic dynamics, and ecosystem evolution. Through quantitative and multidisciplinary analysis, the putative coprolites were attributed to crocodilian producers, leading to the establishment of a new ichnogenus and species, Crococopros naduongensis igen. et isp. nov., based on distinct characteristics and comparisons. The study provides compelling evidence of an ancient river or lake-like environment dominated by diverse crocodilian fauna, indicating a thriving food chain in the Na Duong Basin. The findings also highlight the remarkable richness of ichnofauna, fauna, flora, and the presence of a favorable climate, confirming the area as a significant fossil Lagersta¨ tte in Southeast Asia. Overall, this study offers a unique snapshot of the past, providing valuable insights into the regional ecosystem and significantly contributing to our understanding of paleoenvironmental conditions and biotic interactions.