Fossil Nelumbonaceae from the La Colonia Formation (Campanian–Maastrichtian, Upper Cretaceous), Chubut, Patagonia, Argentina

Abstract

We describe here fossil leaves and fruits assignable to the family Nelumbonaceae Dumortier 1828. Fossils were collected at the Cañadón del Irupé locality, La Colonia Formation (Campanian–Maastrichtian, Upper Cretaceous), Chubut Province, Patagonia, Argentina. The fossil leaves are simple, with symmetrical and peltate lamina, orbicular in shape, and an entire margin. The venation is truly actinodromous with at least 15 primary veins, the secondary veins are poorly developed and intercalated with the primary veins, the third category vein is opposite, and the areoles are well-developed and 4- to 5-sided. These features are characteristic of the extant genus Nelumbo Adamson 1763, and the presence of these characters in the fossils allows their placement within this genus. Reproductive structures, similar to the fruit-receptacle of Nelumbo with fruits in situ, were found associated but not in organic connection with the leaves. These fossils constitute the only and oldest record for the family in the Southern Hemisphere. This record indicates that Nelumbo was more widespread in the past than today.