Water fern spores (Salviniales) from the Late Cretaceous of Patagonia, Argentina

We describe a water fern spore assemblage from the Maastrichtian La Colonia Formation, Chubut Province, Patagonia, Argentina. The includes three species of Azolla (A. andreisii sp. nov., A. coloniensis, and 1), two Azollopsis intermedia tomentosa), Crybelosporites pannuceus, Gabonisporis cristata, Ghoshispora sp., Grapnelispora loncochensis, Molaspora (M. lobata M. reticulata), Paleoazolla patagonica. tomentosa, intermedia, G. reticulata are recorded for first time in Southern Hemisphere. constitutes southernmost record genus its mention In addition, is emended to include megaspore apparatuses with more than one megaspore. This most diverse so far known South America substantiates significant radiation that aquatic ferns underwent worldwide at end-Cretaceous. Furthermore, it also implies presence widespread suitable paleoenvironments allowed establishment rapid evolution these plant communities Patagonia.