A juvenile Nypa burtini (Brongniart) Ettingshausen from the early Eocene of Southern Egypt

Abstract

This study reports the first confirmed occurrence of Nypa Steck fruits and a leaf fragment from the early Eocene Dungul Formation in southwestern Aswan, Egypt. The fossils, assigned to Nypa burtini (Brongniart) Ettingshausen, extend the known distribution and morphological variation of the genus in North Africa, adding to the limited fossil record of mangrove palms in the region. The fruits exhibit notable size variation, a trait also observed in modern and fossil Nypa, which is influenced by biological, environmental, and geological factors and often leads to taxonomic misinterpretations. The geographic pattern of early Nypa fossils suggests a stronger Laurasian affinity, with the oldest and most abundant records concentrated in areas bordering the Tethys Ocean, such as Southeast Asia, India, and parts of Africa. This supports the view that Nypa originated in tropical coastal settings of Laurasia and dispersed globally during the Paleocene–Eocene. This finding provides new insights into the paleoecology and paleobiogeography of Nypa in North Africa, with the modern Southeast Asian distribution of Nypa fruticans representing the last remnant of a once-widespread lineage.