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Abstract: The sediments of La Rinconada mine (Ribesalbes-Alcora basin, Province of Castellón, Eastern Spain) have yielded one of the Early Miocene''s richest megafloral assemblages in the southwestern Mediterranean. At this site, we have found a large amount of leaf compressions and impressions without preserved cuticle. We have identified a total of 31 species of vascular plants: 1 horsetail, 1 fern, 4 conifers, 23 arboreal or bushy dicotyledoneous angiosperms and 2 monocotyledoneous angiosperms. These fossils reveal the presence during the first half of the so-called Miocene Climatic Optimum of a fluvial-lacustrine flora with well diversified mixed broadleaved deciduous and coniferous taxa. Arctotertiary elements dominate the assemblage, whereas Palaeotropical taxa scarcely occur. The occurrence of Trigonobalanopsis exacantha and Trigonobalanopsis rhamnoides is conspicuous as these are common in humid subtropical evergreen vegetation during the climatic optima in the European Oligocene and Miocene. In the La Rinconada outcrop, there is a noteworthy lack of some taxa such as Juglandaceae, Nyssa and Quercus in comparison with other contemporaneous European floras. [Copyright &y& Elsevier]

Abstract: The native or allochthonous nature of certain extant species of the Iberian Peninsula is a matter of some controversy given our lack of knowledge regarding the survival and extinction processes to which they have been subject. The aim of the present work is to provide a review of the current knowledge regarding these processes during the Quaternary. The Middle Pleistocene Transition was a period of noticeable disappearance of Arctotertiary taxa in the Iberian Peninsula, related to the alteration in glacial cyclicity and climate change, including an increase in the severity of glaciations, a reduction in the length of the interglacial periods, and increased dryness during the coldest times. It is difficult to maintain that human activities played any important part in the complete or near-complete disappearance of some taxa during the Quaternary. In the Late Pleistocene and Holocene, however, the extinction of Cedrus, Picea and Carpinus might be related to climate change, competition with other taxa, and anthropogenic disturbances. In contrast, the extreme reduction or even complete disappearance of Platanus or Syringa seems to be due to natural causes alone. The available geological, molecular and palaeobotanical data suggest that some Arctotertiary taxa persisted over long periods of time during the Quaternary in the Iberian Peninsula. Indeed, the fossil record of one important group of taxa, including Castanea, Ceratonia, Carpinus and Juglans, shows its continued presence throughout the Quaternary. [ABSTRACT FROM AUTHOR]

Abstract: The Cal Guardiola site, discovered during the construction of an office building in the centre of Terrassa (Province of Barcelona, NE Spain), is home to one of the richest deposits of lower–middle Pleistocene flora in the Iberian Peninsula. The site contains a large quantity of plant macroremains, including non-carbonised wood, in an exceptional state of preservation. In this work, 100 wood fragments were analysed along with 25 pollen samples and 2 coprolites, all from the same horizon. These remains revealed the presence of a mixed deciduous forest with significant numbers of Quercus (Quercetum mixtum). Thermophilous, meso-hygrothermophilous and river forest species were also present, including some taxa rarely recorded for the Pleistocene, e.g., the mesocratic group of species represented by Juglans, Carya and Platanus. Fossil wood of Aesculus was also identified; this is the first Pleistocene reference of this species in Iberia. In this open Mediterranean forest, several remarkable gymnosperms were present. For example, Pinus haploxylon-type pollen was identified, demonstrating the survival of this group of conifers during the lower Pleistocene in the Iberian Peninsula. Pollen of Taxodiaceae was also found — the first reference of this family for the Iberian Pleistocene-showing these taxa survived on the Peninsula until the lower–middle Pleistocene transition. Warm-temperate and humid conditions prevailed during this interval; clear indications of an interstadial episode were observed. [Copyright &y& Elsevier]

Abstract: The aim of this work is to provide a first approach to the evolution of Iberia''s vegetation during the Cenozoic (with the exclusion of the Quaternary). The Palaeogene was floristically defined by Palaeotropical elements forming tropical/subtropical rainforests, mangrove swamps, edaphically-mediated laurophyllous forests and leguminous-sclerophyllous communities. During the Miocene, Iberian landscapes were drastically modified due to geographic and climatic changes (mainly cooling and aridification) changes. Open, steppe-like environments developed towards the interior of the peninsula and Arctotertiary elements invaded mountainous and riparian ecosystems, coexisting with or becoming part of evergreen, broadleaved forests of Palaeotropical species. From the Late Miocene onwards these forests suffered changes due to the extinction of taxa, the impact of environmental change on the survivors, and the perturbations caused by the arrival of further Arctotertiary elements. However, several Palaeotropical taxa overcame the environmental and climatic changes of the Miocene and Pliocene to form a part of the modern flora of the Iberian Peninsula. [Copyright &y& Elsevier]