The Charophyte Fossil Record On The Iberian Peninsula: A Synthesis

Iberia was first an island and then a European peninsula during most of the Earth’s history. This along with a long-lasting non-marine record has determined that fossil charophytes are wellrepresented and show significant particularities. As a matter of fact, the Iberian Peninsula is one of the best suited regions of Europe in which to study the charophyte fossil record from the Jurassic to the present. Middle and Late Jurassic charophyte assemblages are represented in the Lusitanian basin (Portugal). They show dominance of the family Porocharaceae in many of the environments available for charophytes. Lower Cretaceous charophytes, dominated by clavatoraceans, have been more studied in the Iberian Chain, where this family achieved high diversity. Also, many European charophyte biozones of this interval are based on Iberian clavatoraceans and have their stratotypes in the Iberian Chain. Upper Cretaceous charophytes of the Iberian Peninsula have been more studied in the Campanian of the Southwestern Iberian Chain (Serranía de Cuenca) and in the Maastrichtian of the south-Pyrenean basins (Catalonia). The floras show important affinity with those from southern France, which is not surprising since both regions were part of the so-called Ibero-Armorican Island. The Upper Cretaceous charophyte record from the southern Pyrenees is significant because it contains a reference section enabling us to define the Cretaceous-Palaeogene boundary based on charophytes in the Àger basin. Palaeogene charophytes from Iberia are best known from studies devoted to the Ebro foreland basin, where a detailed biozonation of the Eocene and Oligocene has been proposed. The charophyte assemblages were composed of a mixture of fossil and present-day genera and included both typical European species as well as endemic taxa. Neogene charophytes from Iberia are poorly known, but a number of studies have been performed, mainly in Central Spain and in the Ebro basin.