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The deposits of the As Pontes Basin in north-west Spain yield extraordinarily well-preserved microfloral assemblages that have unmatched diversity within the European Oligocene. The comprehensive examination of 300 miospore taxa has led to the discovery of two new fossil pollen genera, Eucommiopsispollenites gen. nov. and Pistaciapollenites gen. nov., as well as seven new species: Eucommiopsispollenites compactus sp. nov., Eucommiopsispollenites gracilis sp. nov., Nymphaeapollenites asponticus sp. nov., Nymphaeapollenites perforatus sp. nov., Pistaciapollenites heteroporatus sp. nov., Punctilongisulcites cryptornatus sp. nov. and Symplocoipollenites diktyotos sp. nov. Moreover, the botanical affinity and geographic distribution of 13 additional species of particular interest are discussed in detail, because these are either recorded for the first time anywhere within the Paleogene (Lythraceaepollenites bavaricus, Myrtaceidites myrtiformis, Punctilongisulcites punctiechinatus, Rhuspollenites ornatus and Vitispollenites tener), in the Iberian Peninsula (Aglaoreidia pristina, Diospyrospollenites ovalis, Pseudospinaepollis pseudospinosus, Reevesiapollis reticulatus and Tricolporopollenites vancampoae), or are studied for the first time using scanning electron microscopy (SEM) (Pentapollenites regulatius, Polycolpites helmstedtensis and Triporopollenites robustus). SEM analysis has enabled the conclusive botanical assignment of two species: Polycolpites helmstedtensis, with affinity to the extant tropical genus Eriandra, and Triporopollenites robustus, related to Myricaceae. In view of these affinities, new combinations are proposed accordingly: Polygalacidites helmstedtensis comb. nov. and Myricipites robustus comb. nov. The results of this study carry significant biostratigraphic and palaeobiogeographic implications at a regional and wider, continental scale. Firstly, the similarities of the As Pontes microflora with other Oligocene assemblages located various thousands of kilometres apart indicates the spread of a relatively homogenous broadleaved evergreen flora in Europe and allows for the recognition of Myricipites robustus and the genus Pentapollenites as key biostratigraphic index taxa across the continent. Secondly, the last occurrence datums of thermophilous taxa that became extinct in the Eocene in more northern latitudes indicates that the Iberian Peninsula functioned as a refuge area for thermic vegetation at least since the early Oligocene. [ABSTRACT FROM AUTHOR]

This paper focuses on pollen, spores, non-pollen palynomorphs (NPPs) and certain geochemical elements from the ombrotrophic blanket bog of Zalama (Basque-Cantabrian Mountains, northern Iberian Peninsula), with the support of a robust chronology based on 17 AMS 14C dates. The main results related to the last 8000 years show that, during the early middle Holocene, pines and deciduous forests were the most extensive tree formations. At the beginning of the succession, pines reach 44%, showing regional presence, whereas after 7600 cal. a BP, deciduous forests were particularly abundant. From c. 6500 cal. a BP the pollen diagram constructed from our samples shows the first anthropogenic evidence, linked with the new economic practices related to the Neolithic of the Basque-Cantabrian Mountains. From 3300 cal. a BP the expansion of Fagus sylvatica is particularly clear, and has since then become one of the dominant forest species in this region. We also discuss the Holocene evolution of other noteworthy plant communities in southwestern Europe, such as Taxus baccata, Juglans and shrublands. [ABSTRACT FROM AUTHOR]