the cenozoic vegetation of the iberian peninsula: a synthesis

Review of Palaeobotany and Palynology 162 (2010) 382–402

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Review of Palaeobotany and Palynology

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The Cenozoic vegetation of the Iberian Peninsula: A synthesis

Eduardo Barrón a,⁎, Rosario Rivas-Carballo b, José María Postigo-Mijarra c, Cristina Alcalde-Olivares c,Manuel Vieira d, Lígia Castro e, João Pais e, María Valle-Hernández b

a Instituto Geológico y Minero de España (IGME), Ríos Rosas 23, 28003 Madrid, Spainb Dpto. de Geología, Área de Paleontología, Facultad de Ciencias, Universidad de Salamanca, Plaza de la Merced, 37008 Salamanca, Spainc Dpto. de Silvopascicultura, Unidad de Botánica, Escuela Técnica Superior de Ingenieros de Montes, Universidad Politécnica, Ciudad Universitaria, 28040 Madrid, Spaind Centro de Geologia da Universidade do Porto/Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugale Centrode InvestigaçãoemCiência e EngenhariaGeológica, Dpto. deCiênciasdaTerra, FaculdadedeCiências e Tecnologia, UniversidadeNovade Lisboa,QuintadaTorre,2829-516Caparica, Portugal

⁎ Corresponding author. Fax: +34 91 349 58 30.E-mail address: [email protected] (E. Barrón).

0034-6667/$ – see front matter © 2009 Elsevier B.V. Adoi:10.1016/j.revpalbo.2009.11.007

a b s t r a c t
a r t i c l e i n f o
Article history:Received 18 May 2009Received in revised form 26 October 2009Accepted 23 November 2009Available online 2 December 2009

Keywords:Cenozoicpalaeobotanypalaeovegetation historypalaeoclimatologyIberian Peninsula

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 elementsforming tropical/subtropical rainforests, mangrove swamps, edaphically-mediated laurophyllous forests andleguminous-sclerophyllous communities. During the Miocene, Iberian landscapes were drastically modifieddue to geographic and climatic changes (mainly cooling and aridification) changes. Open, steppe-likeenvironments developed towards the interior of the peninsula and Arctotertiary elements invadedmountainous and riparian ecosystems, coexisting with or becoming part of evergreen, broadleaved forestsof Palaeotropical species. From the Late Miocene onwards these forests suffered changes due to theextinction of taxa, the impact of environmental change on the survivors, and the perturbations caused by thearrival of further Arctotertiary elements. However, several Palaeotropical taxa overcame the environmentaland climatic changes of the Miocene and Pliocene to form a part of the modern flora of the Iberian Peninsula.

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1. Introduction

Currently, the Iberian Peninsula can be said (at least in simpleterms) to be formed by two large phytogeographic territories:damp Iberia, with a Eurosiberian nature, dominated by deciduousforests, and dry Iberia, with a Mediterranean nature, where themost successful plants include evergreens and xerophytes (CostaTenorio et al., 2005). An analysis of the different plant taxa in eachof these territories, taking into account their palaeophytogeo-graphic origins in agreement with Mai (1989, 1991), shows thatmost of the species inhabiting damp Iberia are of Arctotertiaryorigin, while over large areas of dry Iberia the most dominantplants are Palaeotropical in origin (Barrón and Peyrot, 2006). Thissituation is the result of the long process of evolution of theEuroasiatic Cenozoic flora, and is the outcome of local geological,geographic and climatic events.

From a physiographic point of view, some 40% of the IberianPeninsula is occupied by Cenozoic basins, the stratigraphic recordsof deposition being mostly complete and commonly covering theentire Palaeogene to Neogene period (Calvo, 2004). Despite this,

they are still to receive exhaustive palaeobotanical examination;the information currently available is therefore fragmentary.Nevertheless, those studies that have been undertaken have beenof great interest with respect to the evolution of the flora andvegetation of southwestern Europe, showing a local trend forclearly tropical communities dominated by Palaeotropical elementsduring the Palaeogene, and for subtropical or warm-temperatecommunities dominated by a mixture of Arctotertiary andPalaeotropical elements during the Neogene (Postigo-Mijarra etal., 2009).

Using the evidence provided by the palaeobotanical record, theaim of the present work is to describe the different plantlandscapes that existed in Iberia and their evolution over the last65 million years.

2. Themajor paleogeographic and geological features of the Cenozoicin the Iberian Peninsula

In the Upper Cretaceous, Iberia behaved as a plate independentfrom Eurasia and Gondwana that was surrounded by continentalsedimentary and transition environments. The relative absence ofmountain ranges left the entire territory relatively uniform. Duringthe Late Cretaceous–Lower Eocene interval (70–50 Ma), the only

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Fig. 1. Distribution of emerged areas during the late Cretaceous–Lower Eocene interval (modified from López-Martínez, 1989): (a) Areas with no deposits (erosion), (b) continentaldetritic deposits, (c) non-emerged areas with coastal, external platform and oceanic basin deposits, (d) current coastline. Graphic scale: 100 km.

383E. Barrón et al. / Review of Palaeobotany and Palynology 162 (2010) 382–402

emergent areas were the Hesperic, Catalonian-Provençal and EbroMassifs (Fig. 1) (López-Martínez, 1989).

The folding of the Pyrenees began during the Palaeocene;compressive phases occurred during the Eocene from east to west,giving rise to the Pyrenean axial zone. At the end of the Oligocene(Fig. 2a), both the western Pyrenees and the Basque–Cantabrianregions became definitively emerged (López-Martínez, 1989; Alonso-Zarza et al., 2002). During the Miocene, Pyrenean tectonic structuresexperienced reactivation, and a new compressive phase took placethat completed the raising of the Pyrenees as well as the Cantabrianand Iberian Ranges.

The large Cenozoic basins of the peninsula occupy interior andepicontinental positions either isolated from or in connectionwith theMediterranean or Atlantic. Their geographic and geological character-istics strongly reflect their processes of formation and later change(Civis, 2004). The formation of the Ebro Basin began in the UpperPalaeocene–Eocene coinciding with the folding of the Pyrenees.Sedimentation was generally endorheic. The margins of the basinwere characterised by alluvial fans and fluvial deposits, while thecentre of the basin was home to a lacustrine system that producedcarbonated and evaporitic successions (Pardo et al., 2004). Endorheicconditions ended at the end of the Vallesian (∼8.5 Ma), when erosiveevacuation towards the Mediterranean took place (García-Castellanoset al., 2003). According Vázquez-Urbez et al. (2003), the first evidenceof exorheism in this basin can be inferred from deposits of Turolianage (8.7–5.332 Ma).

At the same time, the convergence of Africa and Eurasia led todeformations in the Iberian plate with consequences for the formationof the Duero and Tagus Basins, which came into existence through theraising of the Central system, most likely during the Upper Eocene(Portero and Aznar, 1984).

During the Palaeocene–Eocene interval, the compression to thenorth of what is today the Duero Basin generated a system offaults that contributed to the formation of sub-basins, in whichalluvial fans developed (Alonso-Zarza et al., 2004). After the LateOligocene and throughout the Miocene, endorheic lacustrinesystems became established in the Duero Basin, generating largecarbonate, siliciclastic and evaporite lacustrine sediments withinits centre and in the Almazán Sub-basin. These endorheic

conditions ceased between the Upper Miocene and the LowerPleistocene (Alonso-Zarza et al., 2002).

In the Tagus Basin during the Oligocene–Lower Miocene, theMadrid and Loranca Sub-basins were formed, bringing about thedeposition of shallow lacustrine and fluvio-lacustrine facies (Alonso-Zarza et al., 2004).

At the end of theMiocene, the palaeogeographic configuration of thenorth of the Iberian Peninsula was very similar to the present day. Thesouthern half, however, underwent some notable change. The palaeo-geographic history of the Guadalquivir Basin shows its eminentlyNeogene development. Although sedimentary infilling began in theSerravalian, most of its sediments are Upper Miocene or Pliocene in age(Alonso-Zarza et al., 2002). During the Lower–Middle Tortonian, theGuadalquivir Basin still formedpart of anolder, elongatedeast northeastto west southwest trending feature–the North Betic Straits–whichconnected the Atlantic and Mediterranean domains (Fig. 2b). Thesestraits, along with the so-called South-Rif Straits, compensated for thewater deficit of theMediterraneanby allowing communicationbetweenthe Atlantic and Neotethys-Mediterranean Sea.

In the Middle–Upper Tortonian, most of the olistostromes weredeposited, coinciding with the raising of the eastern mountain rangesthat interrupted communication via the North Betic Straits andgenerated the Guadalquivir Basin (Alonso-Zarza et al., 2002). Theclosure of both the above straits led, about 5.96–5.6 Ma, to the salinitycrisis of the Messinian (CIESM, 2008). For European flora and fauna,this geological event may have led to the creation of important routesof species migration with Africa and Asia. Finally, in the LowerPliocene (Fig. 2c), the Straits of Gibraltar opened, and the connectionbetween the Atlantic and the Mediterranean was restored (Alonso-Zarza et al., 2002).

Elongated depressions running northeast–southwest began toform on the Atlantic face of the western Iberian Peninsula around themiddle of the Eocene. These led to the formation of the Mondego andLower Tagus Basins. The latter, which was formed at the same time asthe Spanish Tagus Basin, was endorheic in nature during thePalaeogene, opening to the Atlantic during the Neogene.

An extensive alluvial plane developed in the interior of theLower Tagus Basin during the Lower and Middle Miocene, andduring the Upper Miocene there were large swampy areas. Until

Fig. 2. Palaeogeographical maps of the Iberian Peninsula during the (a) Oligocene(29 Ma), (b) Middle Miocene (13 Ma) and (c) Pliocene (4 Ma). Black colour: oceanicareas, white colour: marine platform, pale grey colour: emerged lands, dark greycolour: main continental basins. The current Iberian coastline and the main tectonicstructures are indicated. Graphic scale: 300 km.Modified from Paleogeological maps, Project IGCP 369 PeriTethyan Rift Basins, http://www-sst.unil.ch/igcp_369/369_text/igcp369_iberia.htm.

384 E. Barrón et al. / Review of Palaeobotany and Palynology 162 (2010) 382–402

the mid Tortonian their evolution was marked by the erosion ofthe Hesperic massif. After this time, coincidental with the raisingof the Betic Ranges, the Central Portuguese range and theWestern Mountains began to rise. In the Upper Miocene andduring the Zanclean the basin one again showed endorheicfeatures. In the Upper Pliocene the climate of the region becameincreasingly humid and an exorheic hydrographic networkdeveloped, the precursor of what is seen today (Pais, 2004; Paiset al., 2009).

3. Materials and methods

All the published palynological and macrofloristic studies thatfocus on the Cenozoic of the Iberian Peninsula (not including theQuaternary) were taken into account. However, special attentionwas given to a series of locaties (Fig. 3) since the analyses of thepalaeobotanical information they provide allows the floristiccharacterisation of the different periods of the Palaeogene andNeogene, and permits inferences regarding the composition oftheir most representative plant communities. This information alsoprovides insight into certain landscapes of the Cenozoic and theirevolution.

The proposals of the International Commission on Stratigraphy(ICS) and the International Union of Geological Sciences (IUGS)regarding time scales are used throughout this work. The datesproposed by the consulted authors were respected. For the construc-tion of the chronogram (Figs. 4 and 5), the scale proposed byGradstein et al. (2004) was used, correlating the data from Neogenecontinental scales using the proposal of Calvo et al. (1993) and Daamset al. (1998).

Also included in this synthesis are unpublished palynologicaldata from Neogene outcrops chosen for their pollen richness, theirage, and their geographic location (Figs. 6–9). Palynologicalsamples were prepared using standard techniques (Batten, 1999).Some 500–1000 palynomorphs (on up to four slides) wereidentified per sample to determine the species ratios. Pollendiagrams were constructed using Tilia 1.0.1. software (Grimm,2008) to determine the quantitative variation of taxa or groups oftaxa through the successions examined. Aquatic taxa were groupedin all pollen diagrams and are summarized in Table 1. The pollensum was calculated using all taxa, except for the Zaratán pollendiagram in which Pinus was excluded owing to its overrepresen-tation (Fig. 7a). In the pollen diagrams, taxa providing less than 1%of the pollen were not included, although these are shown inAppendix A.

The climate was determined using the coexistence approachmethod (Mosbrugger and Utescher, 1997). This involved the use ofClimStat software and the Paleoflora database, which contains thenearest living relatives of more than 3500 Palaeogene and Neogeneplant taxa, together with their climatic requirements (derivedfrom meteorological station records located within their areas ofdistribution). The climatic variables taken into consideration(Table 2) were: mean annual temperature (MAT), mean temper-ature of the coldest month (CMT), mean temperature of thewarmest month (WMT), and mean annual precipitation (MAP).However, the main aim of the calculations undertaken was not toinfer climatic trends but to obtain information on the types ofvegetation that existed in Iberia. For this, comparisons with datesfor fossil plant associations were made, and with the findings ofcurrent climate-vegetation studies (Wolfe, 1978, 1979; Pais, 1986;Fauquette et al., 1998, 1999; Suc et al., 1999; Kvaček, 2005, 2007).Generally, the climatic intervals calculated from pollen and sporeinformation were larger than those derived from megaremains, aconsequence of the presence of regional and extra-regionalelements within the pollen assemblages studied (see the data

http://www-sst.unil.ch/igcp_369/369_text/igcp369_iberia.htm

http://www-sst.unil.ch/igcp_369/369_text/igcp369_iberia.htm

Fig. 3. Selected outcrops mentioned in the text. Star: Oligocene, 1) Cervera (Lleida province, NE Spain), 2) As Pontes lignite mine (A Coruña province, NW Spain). Circle: Miocene,3) Izarra (Álava province, N Spain), 4) Lisbon area and S141 Borehole (Vale do Tejo region, Estremadura, W Portugal), 5) Ribesalbes (Castellón province, E Spain), 6) Rubielos deMora(Teruel province, E Spain), 7) Puente de Toledo (Madrid province, Central Spain), 8) Zaratán (Valladolid province, Central Spain), 9) Belorado (Burgos province, N Spain), 10) LaCerdaña (Lleida province, NE Spain), 11) Gibraleón (Huelva province, S Spain). Triangle: Pliocene, 12) Apostiça (Sesimbra region, Setúbal Peninsula, W Portugal), 13) Casa del Pino(Huelva province, S Spain), 14) Can Albareda (Barcelona province, NE Spain), 15) Les Torrenteres (Papiol, Barcelona province, NE Spain), 16) Rio Maior (Santarém region, Ribatejo, WPortugal), 17) Vale do Freixo (Pombal region, Beira Litoral, W Portugal).


provided by miospores and leaves from Rubielos de Mora and LaCerdaña basins in Table 2).

4. Results and discussion

4.1. Early Palaeogene tropical vegetation (65.5–48.6 Ma)

The floras of the early Palaeogene developed in the so-called“greenhouse world”, in which trees were found all around the globe.The Palaeocene initially saw a continuation of the climatic conditionscharacteristic of the Mesozoic; there was even a small increase in themean annual temperature from the Middle Palaeocene (59 Ma) untilthe early Eocene (53 Ma), with a maximum in the Early Eoceneclimatic optimum (Zachos et al., 2001). Evidence provided by thefossil fauna and sediments of the Iberian Peninsula confirms thetropical nature of the climate; this is in agreement with its position inthe European archipelago flanked by the warm Tethys Sea (López-Martínez, 1989; López-Martínez et al., 1999; Tiffney and Manchester,2001).

The lack of continuous section in the scarce sites that have beenfound, and the absence of a precise chronostratigraphic frame-work, only allows a sketch to be drawn of the landscapes of thePalaeocene and Early Eocene. From a floristic standpoint the mostvaluable data are those provided by palynological studies under-taken in the Catalonian–Aragonese regions of the Pyrenees and theBetic Ranges.

According to Knobloch et al. (1993), the palaeobotanical record ofCentral Europe suggests that the floristic changes of the LateCretaceous and Palaeocene were gradual but continuous, with thenumber of modern pollen forms slowly increasing. In this way, theIberian Paleocene palynological assemblages (Haseldonckx, 1973;Médus, 1977; Médus et al., 1988, 1992; López-Martínez et al., 1999)

present higher modern floristic affinities and diversity than theMaastrichtian ones (Médus, 1970, 1972; Solé de Porta and de Porta,1984; de Porta et al., 1985), what also was recorded in China and isrelated to Early–Late Maastrichtian climatic changes (López-Martínezet al., 1999). Contrarily, in North America a loss of pollen and sporediversity is detected during the K/T boundary (Wolfe and Upchurch,1986; Nichols et al., 1990).

During the Palaeogene, the vegetation that developed in Iberiabelonged to that of the Palaeotropical belt, and, according to Batten(1981), to theNormapolles province (which already existed in the LateCretaceous). The Palaeocene forests were home to the first represen-tatives of many genera that exist today (Nichols and Johnson, 2008).During this period, plants that produced Normapolles pollen grainsplus Arecaceae, Ebenaceae, Engelhardia, Ericales, Fagaceae, Magnolia-ceae,Myricaceae,Nyssa, Sciadopityaceae, Symplocaceae and taxodioidconifers, grew close to swampy areas, along with a great abundanceand diversity of ferns (Haseldonckx, 1973; Médus, 1977; Médus et al.,1992; Fernández-Marrón et al., 2004). The importance of conifersin these plant communities should also be highlighted. This wasalso patent in the Maastrichtian of Iberia (Médus, 1970, 1972; Solé dePorta and de Porta, 1984; de Porta et al., 1985). The fewmacrofloristicdata available (López-Martínez et al., 1999) appear to suggest theexistence of evergreen laurophyllous forests that could tolerateseasonal dryness.

The floras of the Lower Eocene suggest associations very similar tothose inferred for the Palaeocene (Médus, 1977; Médus and Colombo,1991), and can be considered strongly thermophilous and evergreen(Collinson and Hooker, 2003). One novelty was the appearance ofpalaeomangrove swamps with Nypa (Fig. 4), the pollen grains ofwhich are abundant (Haseldonckx, 1973). These ecosystems rangedwide across the European archipelago, suggesting a warm, wetclimate for this time. Finally, for the Lower Eocene in the Iberian

Fig. 4. Chronostratigraphic scale chart of the Paleogene according the International Geological Time Scale proposed by Gradstein et al. (2004). The most important events concerningthe Paleogene Iberian vegetation have been indicated.


Table 1Genera and families considered in pollen diagrams (Figs. 6–9) as aquatic taxa.

Taxa Barranco Casas Puente de Toledo Zaratán Belorado La Cerdaña Gibraleón Casa del Pino Can Albareda Les Torrenteres Rio Maior

Alisma * * *Alismataceae * * *Callitriche *Cyperaceae * * * * * * * *Epilobium * * *Hippuris *Lythrum * * *Myriophyllum * * * * *Nuphar * * * *Nymphaea * *Nymphaeaceae * * *Polygonum persicaria type *Potamogeton * * * * * * *Sparganium * * * * *Sparganiaceae–Typhaceae * *Trapa *Typha * * * * * * * *Utricularia *


southwest (in the Betic Ranges), Solé de Porta et al. (2007) suggesteda tropical–subtropical rainforest vegetation including Arecaceae andpteridophytes.

4.2. Climate-inducedmodifications in the Palaeotropical vegetation of Iberia

From the Late Eocene onwards there was a growing trend towardsaridity, which led to the continentalisation of Eurasian climates. Thiswas accompanied by a fall in temperatures around the world (López-Martínez, 1989; Mai, 1989). From the climatic optimum of the LowerEocene (Fig. 4) until the beginning of the Oligocene (~34 Ma),temperatures continued to fall, culminating in the Eocene–Oligocenetransition and its long period of glaciation (400,000 ka; the Oi-1glaciation; Fig. 4). This glaciation coincidedwith the appearance of theAntarctic ice cap (Miller et al., 1991; Zachos et al., 2001; Mosbruggeret al., 2005). The observed trend to greater dryness and greater coldfrom the Late Eocene had notable repercussions for the floras ofCentral Europe and North America (Collinson, 1992; Wolfe, 1992;Knobloch et al., 1993). According toMosbrugger et al. (2005), this wasa time of marked seasonality with particularly cold winters. In theIberian Peninsula, the climate changes that culminated in the Eocene–Oligocene Transition were marked by the disappearance of 32Palaeotropical genera (Postigo-Mijarra et al., 2009).

4.2.1. Changes in vegetation during the Late EocenePinus pollen dominates assemblages from the very early

Bartonian record of the Pyrenees (Fig. 4). This has been relatedto a fall in temperatures and an increase in seasonality (Hasel-donckx, 1973). The results of palynological studies of Bartonian–Priabonian sediments from the Ebro Basin indicate this period tohave been a time when different Palaeotropical plant communitiesexisted, including mangrove swamps, forests associated withswampy areas, and extrapalustrine forests, all of which developeddue to the warm, wet climate (Cavagnetto and Anadón, 1994,1996). These ecosystems were inhabited by taxa such as Alangium,Alchornea, Austrobuxus, Bignoniaceae, Croton, Dissilaria, Paedicalyxand Grewia that today are confined to tropical and subtropicalareas. The genera Acrostichum, Avicennia, Aegiceras, Brownlowia,Pelliceria, Heritiera, and especially Nypa, defined the mangrovesthat existed during the Upper Eocene (Álvarez Ramis, 1982;Cavagnetto and Anadón, 1996).

For the Priabonian of the Ebro Basin, taxa such as Acacia, Albi-zia, Combretum-type and Terminalia–plants associated with open,

dry environments–have been detected (Cavagnetto and Guinet,1994; Cavagnetto and Anadón, 1996). These provide the firstevidence of the climate change that occurred in the Late Eocene inIberia, and indicate a change in the landscape as tropical forestsbecame open tropical/subtropical sclerophyllous forests (Fig. 4).Megafossil woods belonging to the Cupressaceae family (Cupressi-Vallin = Tetraclinis sp.?; Plate I, fig. 1) have been recovered in theMondego Basin, along with the remains of leguminous plants(Leguminoxylon teixeirae Vallin; Plate I, fig. 4), as well as abundantPinus pollen, all of which indicates the existence of plant formationsadapted to dry climates (Pais, 1992). Formations of such xerophyticplants seem to have been restricted to the south of Europe during thisperiod (Utescher and Mosbrugger, 2007), a time when Normapollesplants apparently disappeared. The Iberian final records for the latterare those for the Upper Eocene of the Catalonian Pyrenees (Sitter,1961).

4.2.2. Evergreen subtropical Oligocene–Miocene vegetation (33.9–13.82 Ma)The fossil record of the Oligocene for Iberia shows that the

Ebro Basin during the Rupelian was home to a subtropical florawith 34–49% of its components being megathermal or mega-mesothermal and well adapted to periods of seasonal drought(Sanz de Siria, 1992; Cavagnetto and Anadón, 1996; Hably andFernández-Marrón, 1998). Notophyllous species belonging toLauraceae (Plate I, fig. 2), Myricaceae and Ficus were widespreadbut linked to areas where the soil water was sufficient and wherethe topography was favourable (Sanz de Siria, 1996). Theselauroids were mixed with species of the genus Quercus and thefamilies Cupressaceae, Fabaceae, Juglandaceae, Myrtaceae, Sapin-daceae and Sapotaceae, forming an evergreen, sclerophyllous–laurophyllous forest.

In the northwest of the peninsula, the palynoflora reflected in theRupelian–Chattian transition levels (Cavagnetto, 2002) reveals theexistence of Palaeotropical trees and an abundance of ferns andmembers of the Pinaceae, Podocarpaceae, taxodioid conifers, Cyca-daceae, Sapotaceae, Symplocaceae, Malvaceae, Araliaceae, Theaceae,Cyrillaceae, Juglandaceae, Fagaceae and Arecaceae (Fig. 4). Theseaccounted for some 49% of the taxa in the Ebro Basin at this time. Openareas with herbaceous vegetation cannot be inferred from this data,nor is there evidence of sclerophyllous formations (Cavagnetto andAnadón, 1996).

The temperature intervals for the Ebro Basin (Cervera outcrop)and Peninsular northwest (As Pontes lignite mine) (Fig. 3)

Fig. 5. Chronostratigraphic scale chart of the Marine Mediterranean Neogene based on the International Geological Time Scale (Gradstein et al., 2004). The Land Neogene WesternEuropean Stages have been correlated with the Marine Mediterranean ones according the frameworks proposed by Calvo et al. (1993) and Daams et al. (1998). The most importantevents concerning the Neogene Iberian vegetation have been indicated.


Table 2Climatic variables calculated using the Coexistence Approach method (Mosbrugger and Utescher, 1997) for selected Iberian Cenozoic outcrops. The obtained data are not inaccordance with those exposed by Jiménez-Moreno et al. (2009).

Site Age Numberof taxa

Material Reference MAT CMT WMT MAP

Cervera (Ebro Basin) Rupelian(Lower Oligocene)

77 Leaves Sanz de Siria (1992) 17–18.5 °C 5.6–11.7 °C 27.2–27.8 °C 1255–1355 mm

As Pontes (NW Spain) Rupelian/Chattian(Oligocene)

167 Miospores Cavagnetto (2002) 17.2–18.4 °C 6.6–7.0 °C 27.3–27.8 °C 1300–1322 mm

Izarra Basin (N Spain) Aquitanian(Lower Miocene)

28 Leaves Barrón et al. (2006a) 15.5–15.6 °C 0–4.8 °C 26.4–26.7 °C 867–1237 mm

Izarra Basin (N Spain) Aquitanian(Lower Miocene)

87 Miospores Barrón et al. (2006a) 16.2–18.5 °C 5.5–11 °C 25.8–27.6 °C 956–1349 mm

Lisbon area (Lower TagusBasin, Portugal)

Aquitanian(Lower Miocene)

45 Miospores Pais (1981) 15.6–21.7 °C 5–13.6 °C 24.7–27.9 °C 1096–1520 mm

Ribesalbes (E Spain) Lower Aragonian(Lower Miocene)

32 Leaves Fernández-Marrón (1979) 13.6–15.8 °C 2.2–4.8 °C 26.5 °C 1000 mm

Rubielos de Mora (E Spain) Lower Aragonian(Lower Miocene)

33 Leaves Barrón and Diéguez (2001) 12.9–16.1 °C 0.6–2.7 °C 23.8–25.6 °C 1036–1058 mm

Barranco Casas (Rubielosde Mora, E Spain)

Lower Aragonian(Lower Miocene)

94 Miospores This work 17.2–18.3 °C 7.7–10.2 °C 25.0–26.4 °C 1217–1384 mm

S 141 borehole (LowerTagus Basin, Portugal)

Burdigalian(Lower Miocene)



Serravallian(Middle Miocene)

31 Miospores Pais (1981) 15.7–21.1 °C 2.9–13.3 °C 25.7–28.3 °C 1096–1355 mm

Puente de Toledo (MadridSub-basin, C Spain)

Aragonian(Middle Miocene)

94 Miospores This work 16.5–18.5 °C 5.5–13.1 °C 20.3–23.1 °C 887–1167 mm

Zaratán (Central DueroBasin, C Spain)

Aragonian–Vallesian(Middle–UpperMiocene)

62 Miospores Rivas-Carballo (1991) 15.6–17 °C 5–10.3 °C 24.7–26 °C 823–1372 mm

Belorado (NE Duero Basin,C Spain)

Aragonian–Vallesian(Middle–UpperMiocene)

68 Miospores Valle-Hernández et al. (1995) 15.6–18.4 °C 6.4–12.5 °C 24.7–27.7 °C 823–1167 mm


Early Tortonian(Upper Miocene)


La Cerdaña Basin (NE Spain) Vallesian (UpperMiocene)

53 Leaves Barrón (1996) 14.4–15.8 °C 3.7–5.2 °C 25.7–26.4 °C 1231–1355 mm

La Cerdaña Basin (NE Spain) Vallesian (UpperMiocene)

78 Miospores This work 16.5–17 °C 0.9–10.03 °C 23.6–26.3 °C 887–1167 mm

Gibraleón (GuadalquivirBasin, SW Spain)

Messinian (UpperMiocene)

47 Miospores Peñalba (1985) 15.6–19.5 °C 5–13.5 °C 24.7–26.4 °C 823–1613 mm

Casa del Pino (GuadalquivirBasin, SW Spain)

Zanclean (Pliocene) 49 Miospores Peñalba (1985) 13.3–18.3 °C 5.6–10.2 °C 23.6–26.4 °C 735–1384 mm

Lower Tagus Basin(Portugal)

Zanclean (Pliocene) 52 Miospores Vieira (2009) 15.7–17.4 °C 6.6–8.3 °C 24.7–27 °C 1096–1355 mm

Can Albareda, base(NE Spain)

Piacenzian (Pliocene) 40 Miospores This work 11.4–19.5 °C 0.4–13.3 °C 21.7–26.4 °C 631–1355 mm

Can Albareda, top(NE Spain)

Piacenzian (Pliocene) 72 Miospores This work 15.7–17 °C 5–10.03 °C 24.7–26.4 °C 1096–1372 mm

Les Torrenteres (NE Spain) Piacenzian (Pliocene) 92 Miospores This work 15.6–17 °C 5.6–9.6 °C 21.7–26.4 °C 1096–1281 mmRio Maior (LowerTagus basin, Portugal)

Piacenzian–Gelasian(Pliocene)

130 Miospores Vieira (2009) 16.4–17 °C 6.6–10.3 °C 25–26 °C 1194–1278 mm


obtained by the coexistence approach method are practicallyidentical (Table 2), with both enjoying subtropical climates. Therainfall for the Peninsular northeast was slightly higher than in theEbro Basin.

The floras of the Lower Miocene in Iberia showed somesimilarities with those of the Oligocene, although with significantdifferences due to the extinction of many Palaeotropical genera(Postigo-Mijarra et al., 2009). In fact, the lowermost Mioceneoutcrops of As Pontes e Izarra (Médus, 1965; Barrón, 1999; Barrónet al., 2006a), the Aquitanian–Serravallian outcrops of the LowerTagus Basin (Castro, 2006; Pais et al., in press), and theBurdigalian–Langhian outcrops of Catalonia (Bessedik, 1985) areall still characterised by Palaeotropical elements such as Simar-oubaceae, aquatic ferns (Plate I, fig. 3), Malvaceae, Sapotaceae,Engelhardia, etc. The results of the calculations for the climate ofthe Izarra Basin (Fig. 3; Table 2) indicate conditions similar tothose in East Asia where broadleaved sclerophyllous subtropicalforests are now found (Wolfe, 1979). The mean annual temper-

ature of the Lower Tagus Basin (Lisbon area; Fig. 3) during theAquitanian appears to have been between 15.6–21.7 °C and thearea appears to have enjoyed abundant rainfall (Pais, 1986;Table 2).

From the Oligocene onwards, communities of leguminous plants(forests or shrubs) started to dominate the landscape of many Iberianregions (Fig. 4). These communities included species of the generaAcacia, Albizia, Caesalpinia, Cassia, Hylodesmum, Mimosa and Gledit-sia, and sclerophyllous taxa such as Paliurus, Ziziphus, Rhamnus andTetraclinis. These have been recorded in Iberia since the LowerOligocene (Cavagnetto and Guinet, 1994), and were very wellrepresented in the Lower and Mid Miocene in Catalonia (Sanz deSiria, 1994). The most recent data for these communities come fromthe late Zanclean of the Guadalquivir Basin (Barrón et al., 2003). Overthis long period of time the above plant communities changed incomposition depending on the climate. On some occasions they mayhave made up mixed formations with conifers, along with remnantsof the genus Tetraclinis during drier times (Sanz de Siria, 1992; Barrón,

http://dx.doi.org/10.1016/j.revpalbo.2009.08.001


1999), and with Pinaceae when times were comparatively wetter(Fernández-Marrón, 1979).

On the shores of the Tethys Sea changes were also underway in thecomposition of the mangroves, which from the early Aquitanian untilthe Lower Tortonian were characterised by Avicennia (Bessedik, 1985;Bessedik and Cabrera, 1985; Jiménez-Moreno and Suc, 2007). Thetolerance of this genus to grow and reproduce across a broad range ofclimatic, saline, and tidal conditions and to produce large numbers ofbuoyant propagules (Duke et al., 1998) allowed it to colonize thewestern coastlines of the Mediterranean during the Miocene andtoday may explain its ubiquitous presence in mangrove habitatsaround the world. Mangroves with Rhizophora survived in southeast-ern Iberia until the Pliocene (Postigo-Mijarra et al., 2009).

4.3. Laurel forests (notophyllous broadleaved evergreen forests)

According to Mai (1989), laurel forests were one of the mostimportant vegetation types making up the Palaeotropical geoflora ofthe European Palaeogene and Neogene.

The first compelling data for Cenozoic laurel forests in Iberiacome from the Upper Rupelian of the Ebro Basin (Cervera outcrop;Figs. 3 and 4). In a macrofloristic study Sanz de Siria (1996)indicates the existence of mixed lauroid communities of Lauraceae(Plate I, fig. 2) and Fagaceae plus members of Ebenaceae,Juglandaceae, Myrtaceae, Sapindaceae and Ficus; these developedin humid environments at altitudes of 400–500 m (similar to thatof the oak-type laurels of southeastern China). The leaf assem-blages examined also showed a high number of sclerophyllous taxabelonging to the families Anacardiaceae, Cupressaceae, Fabaceaeand Rhamnaceae, whose presence is confirmed by palynologicaldata (Cavagnetto and Anadón, 1996). Unlike that indicated by Sanzde Siria (1996), this suggests that extremely dry conditionsprevailed in the area during this time. However, the strongpresence of laurel leaves in associations greater in number thanmicrophyllous associations might indicate that the laurels werefound close to water — and therefore in the area wherefossilisation was most likely. Thus, the laurel forests that existedduring the late Lower Oligocene in the Ebro Basin must haveexisted for much of the year on the water to be found in the soil,and probably made up riparian communities. Such formationsgrowing in a semi-arid–arid tropical context have no modern-dayanalogues, and may relate to the edaphically-mediated formationof laurel-conifer forests discussed by Mai (1989).

Dry conditions prevailed in many areas of the Peninsula during theMiocene. Thus, although riparian laurel woods persisted in differentbasins, the plant communities to which they belonged becameincreasingly characterised by Arctotertiary taxa. Edaphically-mediat-ed laurel forests have been recorded for the Lower Miocene of theIzarra Basin (Barrón, 1999) and for the Lower and Middle Miocene ofCatalonia (Sanz de Siria, 1994). According to Utescher et al. (2007),during the Langhian the Peninsular northeast represented the part ofEurope with the greatest diversity of tree taxa in this type of forest.

From the Aquitanian, laurel forests also appear to be linked tohumid sea-influenced or mountainous areas (Fig. 5). This is thecase for those which developed in the La Cerdaña Basin (Fig. 3;Barrón, 1996; Barrón and Diéguez, 2005). The growth of theseforests in the Vallesian may have been related to the orography ofthe area and the orientation of its peaks. These forests possessedelements reminiscent of those that exist today in Macaronesia,which include different genera of Lauraceae, Myricaceae and

Fig. 6. (a) Pollen diagram of Barranco Casas outcrop (western Rubielos de Mora Basin, E Spai(eastern sector of the Sub-basin of Bellver, NE Spain). For stratigraphic details see Barrón andSpain). For stratigraphic details see Peñalba (1985).

Myrsinaceae. They must also have included magnolias and oakssuch as Quercus drymeja Ung. and Q. neriifolia Al. Braun.

The last laurel forest records for the IberianPeninsula are thoseof thePiacenzian outcrops at Baix Llobregat (Barcelona), Ciurana (Girona) andaround Tortosa (Tarragona) (Sanzde Siria, 1987). They all share the traitthat their fossils do not come from mountainous areas but from placesclose to the Mediterranean coast. In fact, trees with lauroid leavesbelonging to the genera Laurus, Persea, Cinnamomum, Benzoin andQuercus represent 47% of the plant remains at the Papiol site.

The above data show that laurel forests were of greatimportance in the landscapes of much of Cenozoic Iberia. Incontrast to that indicated by Kovar-Eder et al. (2006), they appearto have occupied more than 30% of its territory from the Tortonianto the Piacenzian, growing everywhere from mountainous to low-lying areas.

4.4. Appearance and spreading of Arctotertiary vegetation

During the Upper Eocene, genera of Arctotertiary origin such asAlnus, Castanea, Salix and Ulmus began to be represented (Fig. 4),although they were not very common and were always linked toriparian formations. During the Oligocene the appearance of Arcto-tertiary elements persisted. The above genera became consolidatedand Abies, Acer, Carpinus, Celtis, Cornus, Corylus, Fagus, Fraxinus, Ju-glans, Liquidambar, Ostrya, Picea, Populus, Sambucus, Tsuga and Zelk-ova appeared in the assemblages for the first time (Cavagnetto andAnadón, 1996; Cavagnetto, 2002).

The Oligocene–Miocene boundary (23 Ma) was characterisedby a strong glacial maximum lasting a brief 200 Ka. This wasfollowed by a series of less intense, intermittent glaciations (Milleret al., 1991; Paul et al., 2000; Zachos et al., 2001; Billups et al.,2004) and an accompanying fall in global temperatures. Accordingto Mosbrugger et al. (2005), this cooling was especially noticeableduring winter. During this time, the major floral changes in CentralEurope involved the coexistence of an interaction betweenPalaeotropical and Arctotertiary plants, including the substitutionof the former by the latter (Mai, 1989). The data availableregarding plant extinctions suggests that in the Iberian Peninsulathese changes in flora were slower and took place over theNeogene (Postigo-Mijarra et al., 2009).

In the Lower Miocene of As Pontes (Fig. 3; Médus, 1965), thetransformation of a swampy vegetation with Palaeotropical elements(including Myricaceae, Simaroubaceae, Anacardiaceae, Cyrillaceaeand Engelhardia) to one of Arctotertiary genera such as Betula, Cory-lus, Carpinus and Carya can be clearly seen (Fig. 5).

At the beginning of the Burdigalian (~19 Ma) in the LowerTagus Basin (S 141 Borehole; Fig. 3), the deciduous tree florabegan to take on more importance than the subtropical evergreenand coniferous flora (Pais, 1986). However, at the beginning of theMiocene climatic optimum, Palaeotropical plants along withconifers once again dominated the subtropical landscapes. Accord-ing to the available palynological (Pais, 1981) and climatic data(Table 2), they appear to have formed notophyllous broadleavedevergreen forests. At the end of the Burdigalian there was a time ofhigh rainfall (Böhme, 2003) that once again allowed the expansionof Arctotertiary vegetation. From then on until the Tortonian thearea seems to have been dominated by a mixed broadleavedevergreen/deciduous vegetation, although humid tropical tosubtropical taxa such as Spirematospermum, Toddalia, Malvaceae(Plate I, fig. 3), and Sapotaceae associated with hydro-hygrophytic

n). For stratigraphic details see Peñalver (2002); (b) pollen diagram of La Cerdaña BasinComas-Rengifo (2007); (c) pollen diagram of Gibraleón outcrop (Guadalquivir Basin, S


genera have been identified for the Serravallian (Pais, 1986; Pais etal., in press.). It may be that mixed broadleaved/deciduousvegetation also existed in the Mid Miocene in the Peninsularnorthwest, as indicated by the pollen composition of the Xinzo deLimia Basin (Alcalá et al., 1996), where Pinaceae, Alnus, Betula,Quercus, Ericaceae, Poaceae and Pteridophyta are represented inconsiderable numbers.

Unlike in the west of the Peninsula, where the Atlantic had animportant impact on the structure of the vegetation during theMiocene, in the rest of the Iberia Arctotertiary vegetation wasrestricted to damp or mountainous areas. The megafloras of theLower Miocene basins of Ribesalbes and Rubielos de Mora (whichare in close geographical proximity; Fig. 3) suggest the climate ofthe latter to have been wetter and cooler, but not so drier andcooler as Jiménez-Moreno et al. (2007) indicated; this isconfirmed by the results of calculations for their CMT and MAP.However, their inferred MAT are similar (Table 2) and illustrativeof a subtropical climate in which notophyllous broadleavedevergreen forests developed. The climatic discrepancy betweenthem is almost certainly conditioned by the fact that theRibesalbes Basin was closer to sea level during the Early Miocene.Its flora had an Arctotertiary component including Alnus, Celtis,Liquidambar (Plate I, fig. 9), Populus and taxodioid conifers(Fernández-Marrón, 1979) that developed in a shoreline area. Incontrast, the Rubielos de Mora Basin was situated at more than900 m above sea level, and here broadleaved evergreen andconiferous forest including ferns (Plate II, fig. 6), Calocedrus,Carya, Cryptomeria, Picea, Pinus, Quercus, Sequoia, Sorbus (Plate I,fig. 5), Zelkova and diverse herbs (Plate II, fig. 1) grew (Barrón andDiéguez, 2001; Barrón et al., 2006b). The palynological data (Fig.6A) seem to suggest a better representation of Arctotertiaryelements than Palaeotropical elements, with periods of predom-inance of conifers alternating with others characterised bydeciduous angiosperm trees (Barrón et al., 2006b; Jiménez-Moreno et al., 2007).

Similarly, the sites of the LaCerdaña (Fig. 3) and La Bisbal (Catalonia)Basins, both of Upper Miocene age, are geographically very close. Theintramontane basin of La Cerdaña developed in the eastern Pyreneesduring the Vallesian. Its palaeobotanical record indicates that, in asubtropical climatic context (Table 2) and owed to its altitude andorography, an ecotone involving notophyllous broadleaved evergreenforests and mixed mesophytic forests existed. The latter showed highdiversity, containing species of the genera Abies, Acer, Betula, Carpinus,Fagus, Fraxinus (Plate I, fig. 8), Ostrya, Parrotia, Pinus (Plate I, fig. 6),Quercus (Plate II, fig. 7), Tilia and Zelkova, thereby relating them to thosethat currently exist in the Euxinic and Hyrcan regions (Barrón, 1996).Palynological studies (Fig. 6b; Appendix A) have confirmed the abovemacrofloristic information, and show that there were times when thepresence of conifers diminished (the RIU level). This might have beenrelated to palaeofires or changes in the environment (greaterdevelopment of lacustrine areas, increase in rainfall etc.).

Unlike at La Cerdaña, the record for the La Bisbal outcrop reveals anArctotertiary vegetation with Alnus, Salix, Platanus, Populus, Ulmusand Pterocarya linked to a riparian environment (Sanz de Siria, 1994).This flora developed under subtropical conditions with mean annualtemperatures of around 18 °C, and at low altitude close to theMediterranean coast. In a manner opposite to that suggested for thelaurel forests, the deciduous Arctotertiary vegetation of the UpperMiocene was not so important in the Peninsular northeast — incontrast to that indicated by Kovar-Eder et al. (2006). This

Fig. 7. (a) Pollen diagram of Zaratán section (Centro Duero Basin, Central Spain). For stratdiagram of Belorado area (Northeastern Duero Basin, N Spain). For stratigraphic details seeSub-basin, Central Spain). For stratigraphic details see Rivas-Carballo (2007).

Arctotertiary vegetation would have had to compete with broad-leaved evergreen forests, causing it to concentrate in very damp orvery cold areas.

4.5. Neogene non-forested lands and steppe-like areas

From the Priabonian onwards, herbaceous plants and bushes suchas Ephedra, Chenopodiaceae, Combretum, Linum, Plumbaginaceae andThymelaeaceae characteristic of dry, open lands (Cavagnetto andAnadón, 1996), began to become more important in the Ebro Basin.Grasses were scarce— a situation to date reported only for Rupelian ofthe Sarral outcrop. Grasses were common in Iberian ecosystems fromthe Upper Burdigalian (Fig. 5), when Catalonia was home to openlands characterised by these plants, along with Amaranthaceae–Chenopodiaceae and Asteraceae (Bessedik, 1985).

From the Langhian onwards, at the very end of the Mioceneclimatic optimum, droughts lasting six months occurred (Böhme,2003). This, along with the significant fall in temperatures of theLanghian-Serravallian, allowed the formation of open, steppe-likeecosystems in the Peninsular northeast, south and centre during theMid and Upper Miocene (Valle-Hernández et al., 2006; Jiménez-Moreno and Suc, 2007).

In general terms, the vegetation of the Aragonian–Vallesian in thecentral domain of the Duero Basin (Zaratán section; Fig. 3) corre-sponded to a steppe of Asteraceae, Amaranthaceae–Chenopodiaceae,Poaceae and Plantago with isolated stands of Juniperus, Quercus andPinus (Fig. 7a) and total absence of Arctotertiary taxa from mid-altitude areas such as Betula, Cathaya, Cedrus, Fagus and Tsuga.Fraxinus dominated riparianwoodswherewaterwas available (Rivas-Carballo, 1991; Rivas-Carballo et al., 1994).

This vegetation changed over the Mid and Upper Miocene. Drysteppeland gave way to thermophilous forests of Juniperus–Quercus,which in turn gave way to prairie land with formations of xerophyticMediterranean vegetation dominated by evergreen Quercus (Fig. 5).The climate inferred for the area was subtropical (Table 2) variation inthe vegetation may therefore have been due to local changes in theclimate.

In areas close to mountain ranges ecotones developed. In theregion of Belorado (Fig. 3), which lies in the Duero Basin where asmall depression formed at the foot of a south-facing mountainrange, ideal conditions were created for the establishment of alocal subtropical microclimate (Table 2). Palynological studies(Valle-Hernández et al., 1995) have revealed the area was home tofar fewer Mediterranean taxa than the centre of the basin, thescarcity of Juniperus, Quercus and Asteraceae pointing to a lesscontinental climate (Fig. 7b). In addition, the evidence suggests theexistence of prairies, deciduous broadleaved forest with Palaeo-tropical elements such as Arecaceae, Malvaceae, Sapotaceae andSchizeaceae, forests of conifers such as Abies, Picea, Cedrus andPinus, and formations of riparian taxa such as Alnus, Clethraceae–Cyrillaceae, Nyssa and Populus (Fig. 7b; Appendix A).

In theAragonian in theMadrid Sub-basin (PuentedeToledooutcrop;Fig. 3), open ecosystems with Asteraceae, Amaranthaceae–Chenopo-diaceae, Poaceae and Plumbaginaceae (Fig. 7c) developed, along withopenMediterraneanwoodland characterised by evergreenQuercus andriparian formations with Pteridophyta, hygrophytic herbs (Plate II,fig. 2), Populus and Ulmaceae (Rivas-Carballo and Valle-Hernández,2004). Scarcely, other mesophylous taxa such as Betula, Carpinus, Carya(Plate II, fig. 4), Fraxinus and Tilia appear (Appendix A). The climatic

igraphic details see Rivas-Carballo (1991) and Rivas-Carballo et al. (1994); (b) pollenValle-Hernández et al. (1995); (c) pollen diagram of Puente de Toledo outcrop (Madrid

Fig. 8. (a) Pollen diagram of Casa del Pino outcrop (Guadalquivir Basin, S Spain). For stratigraphic details see Peñalba (1985); (b) pollen diagram of Can Albareda section (Catalonia,NE Spain). For stratigraphic details see Civis (1977b) and Valle-Hernández (1983); (c) pollen diagram of Les Torrenteres section (Catalonia, NE Spain). For stratigraphic details seeCivis (1977a) and Valle-Hernández (1982).


Fig. 9. Pollen diagram of Rio Maior (F98 Borehole) (Lower Tagus Basin, W Portugal). For stratigraphic details see Vieira (2009).

395E.Barrón

etal./

Reviewof

Palaeobotanyand

Palynology162

(2010)382

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intervals obtained are similar to those calculated for the Duero Basin(Table 2); the two basins may therefore have had similar plant life.

On theAtlanticmargin of the Peninsula during theUpper Burdigalian–Lower Tortonian (Lisbon area; Fig. 3), herbaceous formations wereless important than trees— a consequence of the influence of the ocean.It is possible that their development was linked to coastal zones (Pais,1986). However, in the Lower Tortonian, the climatic intervals in thisarea were similar to those of the Madrid Sub-basin and Duero Basin,reflecting the similar climatic conditions to be found over much of thePeninsula at that time (Table 2). The plant life may therefore have beensimilar in different places.

At the end of the Miocene, the process of aridificationintensified, extending the area occupied by open ecosystems andencouraging the appearance or expansion of several families ofplants adapted to such environments (Singh, 1988). From 9 Ma theIberian Peninsula began to show conditions of great aridity whichintensified during the Messinian. Few data exist for this period, butthe aridity seems to have conditioned the existence of prairies andsteppe in the centre, east and south of the Peninsula (Solé de Portaand de Porta, 1977; Peñalba, 1985; Van Campo, 1989). In theIberian southwest (Gibraleón outcrop; Fig. 3), the Messinianvegetation was characterised by prairies or steppe of Asteraceae,Plantago, Poaceae and Rumex which became progressively enrichedwith Mediterranean-type elements (Arecaceae, Cornus, Oleaceae,Pinus and Quercus) (Fig. 6c). Some subtropical taxa such asClethraceae–Cyrillaceae, Nyssa and Symplocaceae (Fig. 6c; Appen-dix A) were also present (Peñalba, 1985).

4.6. The vegetation in the Pliocene (5.332–1.806 Ma)

The Pliocene is a key period for understanding the origin ofIberia's current vegetation. This period experienced a profoundtransformation of its plant landscapes, largely due to climatechange. The cooling that occurred over the Zanclean, approxi-mately during MIS TG5-MIS GI1, was progressive, leading toperiodic variations in temperature (Lisiecki and Raymo, 2005).Later, in the Piacenzian, a new, brusque cooling occurred about3.3 Ma. Finally, about 2.7–3.3 Ma, isotopic studies show anotheracute cooling occurred over a relatively short period of time(Lisiecki and Raymo, 2005, 2007). A progressive reduction insummer rainfall and the development of a dry season coincidingwith the warmest period of the year occurred around 3.1–3.2 Ma,thus initiating Mediterranean seasonality (Suc and Cravatte, 1982;Bessais and Cravatte, 1988). These changes led to the disappear-ance of the subtropical tree vegetation (Fig. 5), giving way to theMediterranean vegetation that exists today. These climate changesalso led to the extinction of many Palaeotropical and Arctotertiarytaxa (Postigo-Mijarra et al., 2009).

Plate I. Selected Cenozoic Iberian megaremains:

(1). Cupressinoxylon lusitanensis Vallin wood (specimen housed in the Dpto. defrom the Late Eocene of Sobreda (Mondego Basin, Portugal);

(2). Lindera stenoloba (Saporta) Laurent (specimen 32.499, Museu de Ciències N

(3). Salvinia sp. (specimen FM-301, Museo de Ciencias Naturales de Álava, Vitor

(4). Leguminoxylon teixeirae Vallin wood (specimen housed in the Dpto. de Ciêncthe Late Eocene of Sobreda (Mondego Basin, Portugal);

(5). Composite leaf of Sorbus sp. (specimen MPV-1797-RM, Museo de Ciènces NBasin (E Spain);

(6). Male cones of Pinus sp. (specimen MNCNV-4750, Museo Nacional de Cienci

(7). Acer pseudomonspessulanum Unger (specimen UH-Le-26, Dpto. Geodiná(Guadalquivir Basin) (S Spain);

(8). Samara of Fraxinus numana Massalongo (specimen 032, Lladó Collection, Sa

(9). Palmate leaf of Liquidambar pseudoprotensa Andreánszky (specimen Rb-p-54Basin (E Spain). Graphic scale: (1)=150 μm, (4)=200 μm, (2–3, 5–9)=1

After the crisis of the Messinian, the Iberian Peninsula enjoyed awarm-temperate or subtropical climate that lasted throughout thefirst part of the Pliocene. The few palaeobotanical data we have for theZanclean of Iberia come from the Guadalquivir Valley and the TagusBasin. The results of the palynological studies performed by Peñalba(1985) and Valle-Hernández and Peñalba (1987) show that theGuadalquivir Valley (Casa del Pino outcrop; Fig. 3) was home to amixed forest vegetation including conifers, deciduous Arctotertiaryelements (Alnus, Fraxinus Populus and Salix), certain Palaeotropicalelements linked to swampy areas (Taxodiaceae, Clethraceae–Cyrilla-ceae, Myrica, Nyssa, Sapotaceae, etc.), and a high density ofpteridophytes (Fig. 8a; Appendix A). The percentages of evergreenQuercus and Asteraceae at the top of the succession indicate theformation of steppe zones with stands of Mediterranean elements. Atthe end of the Zanclean, these steppes were characterised byleguminous shrubs (Barrón et al., 2003).

The palynological data for the Lower Tagus Basin (Apostiça andVale do Freixo outcrops; Fig. 3) appear to indicate that in theUpper Zanclean broadleaved notophyllous evergreen forests withArecaceae, Castanea/Castanopsis, Engelhardia, Magnolia, Sapotaceae,Symplocos and taxodioid conifers existed (Vieira, 2009; Pais et al.,in press.), with little in the way of Arctotertiary plants. Theseforests developed in a subtropical environment with muchmoisture (the product of rainfall and humidity due to theproximity of the Atlantic) (Table 2).

Palaeobotanical studies of the Piacenzian of Catalonia reveal theexistence of a diverse vegetation which, depending on soil conditionsand altitude, would have been structured as follows (Valle-Hernán-dez, 1982; Sanz de Siria, 1987): halophyte formations close to thecoast (Amaranthaceae–Chenopodiaceae, Armeria, Asteraceae, Ephe-dra, etc.); taxodioid conifers, riparian deciduous trees and hydro-hygrophytic elements such as Myriophyllum, Potamogeton, Ranuncu-laceae and Typha in swampy areas and along rivers; laurel forestswith Lauraceae, evergreen oaks, Magnoliaceae, Myrica, Ficus, Ilex andDiospyros close to sources of water; Arctotertiary and Mediterraneanelements (Cupressaceae, Pinus, evergreen and deciduous oaks, Acer,Olea, Phillyrea, Carya, Carpinus, Poaceae, Amaranthaceae–Chenopo-diaceae, Plantago, etc.) in more or less open plains woodlands; andconiferous forests of Pinus, Picea and Abies in mountainous areas.Evidence also exists that there were moments when the treecomponent becamemuch reduced, giving way to prairies and steppescharacterised by Amaranthaceae–Chenopodiaceae, Poaceae and dif-ferent Asteraceae, such as Armeria (Suc and Cravatte, 1982; Bessaisand Cravatte, 1988).

Palynological studies carried out in Can Albareda and LesTorrenteres sections (Fig. 3), have related the sedimentologicalcharacteristics of the area's outcrops and the different types ofvegetation that existed during the Pliocene. In the sandiest and mostdetritic levels originating frommaterials close to the coast (bottomof

Ciências da Terra, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa)

aturals de la Ciutadella, Barcelona), upper Rupelian (Oligocene) of Cervera (Catalonia);

ia-Gasteiz), Aquitanian (Lower Miocene) of Izarra outcrop (N Spain);

ias da Terra, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa) from

aturals de València) from the lower Aragonian (Lower Miocene) of Rubielos de Mora

as Naturales, CSIC), Vallesian (Upper Miocene) of La Cerdaña Basin, (NE Spain);

mica y Paleontología, Universidad de Huelva), upper Zanclean (Pliocene) of Lepe

badell) from the Vallesian (Upper Miocene) of La Cerdaña Basin, (NE Spain);

, Museo de la Baronía, Castellón), Ramblian–Aragonian (Lower Miocene) of Ribesalbescm.


the Can Albareda diagram; Fig. 8b) Pinaceae is poorly represented,and taxodioid conifers and Pteridophyta are almost completelyabsent. However, Alnus, Rhamnus, Olea-Phillyrea, Ericaceae, decidu-ous Quercus, Plantago and Poaceae appear in much larger numbers.These assemblages stand out because of the importance of Mediter-ranean-type elements that surely existed in woody formationssimilar to those that exist now. However, the marly sedimentsprovided by areas further away from the coast are dominated byPinus and contain a greater amount (and greater diversity) oftaxodioid conifers, evergreen Quercus, Cedrus, Tsuga, Engelhardia,Olea-Phillyrea, Alnus, Poaceae and Amaranthaceae–Chenopodiaceae,along with different pteridophytes (Fig. 8b–c). These last assem-blages may reflect the existence of extralittoral mixed forests withriparian or swamp elements. The calculations for the climate seem toindicate somewhat drier, colder conditions for the base of the CanAlbareda than for its top and Les Torrenteres (Table 2); this agreeswith the available palynological and sedimentological data.

At the end of the Piacenzian and throughout the Gelasian, between1.8 and 2.58 Ma, thermal contrasts became ever greater and theprogressive cooling underway became more intense (Lisiecki andRaymo, 2005). These falls in temperature have been related to theextinction of many (mainly Palaeotropical) taxa (Postigo-Mijarra etal., 2009). In Catalonia, the vegetation inferred by Gelasian macro-remains are characterised by sub-Mediterranean deciduous Arctoter-tiary elements (Fig. 5), especially Quercus cerris L. and Carpinussuborientalis Sap. (Roiron, 1983). Palynological studies indicateforested environments containing Arctotertiary deciduous elementsand conifers plus some residual genera from older periods, such asEngelhardia, Eucommia, Nyssa, Symplocos and Sapotaceae. The latterwould have required warmer and wetter conditions than the abovesub-Mediterranean elements, and were therefore in decline. Duringthe coldest times steppes with Pinus formed (Leroy, 1997).

At Rio Maior (F98 Borehole, Lower Tagus Basin; Fig. 3), during thePiacenzian and Gelasian, a mixed broadleaved evergreen vegetationalmost certainly developed, containing mainly Pinus, Quercus, Engel-hardia,Myrica and Ericaceae (Diniz, 1984a,b; Vieira, 2009). During thefirst part of the Piacenzian, this vegetation was characterised bysubtropical plants typical of swampy areas (taxodioid conifers, Craigia[Plate II, fig. 5], Nyssa, Leitneria), and abundant Pteridophyta, all livingin a subtropical climate (Table 2). Later, coinciding with the climatechange of the middle–late Piacenzian, the pollen diagram evidenceshows the decreasing of the more thermophilous taxa such as Engel-hardia, and an increase in Pinus. Finally, in the Gelasian, the vegetationbecame more open, and was accompanied by a drastic fall in thenumber of thermophilous taxa, ferns and Quercus, and an increase inAsteraceae (Fig. 9).

4.7. Xerophytic Mediterranean vegetation

Palamarev (1989) proposed that the Mediterranean floras aroseout of the subtropical flora living in azonal communities andinfluenced by dry soil conditions in areas with their own micro-climates. This vegetation corresponds to an Eocene association in theDryophylleto–Daphnogenetum-sempervirentifruticosum-type group.From the Oligocene onwards, coinciding with the start of the

Plate II. Selected Neogene Iberian miospores:

(1). Liliaceae gen. et sp. indet., lower Aragonian (Lower Miocene), Barranco Cas

(2). Lithrum sp., Aragonian (Middle Miocene), Puente de Toledo outcrop, Madri

(3). Bombacidites lusitanicus Pais, Serravallian (Middle Miocene), Penedo section

(4). Carya sp., Aragonian (Middle Miocene), Puente de Toledo outcrop, Madrid

(5). Craigia sp., Piacenzian (Pliocene), F98 Borehole, Rio Maior (W Portugal);

(6). Polypodiaceoisporites sp., lower Aragonian (Lower Miocene), Barranco Casas

(7). Quercus sp., Vallesian (Upper Miocene), La Cerdaña Basin, (NE Spain).

formation of arid areas, the pre-Mediterranean elements of thisassociation began to diversify to form subtropical or warm-temperate,broadleaved and deciduous or evergreen communities principallycomprising Lauraceae, Fagaceae, Magnoliaceae, Theaceae and certainconifers.

A large number of the ancestors of modern-day Mediterraneantaxa can be found among Palaeotropical floras which, during theNeogene, had to compete with Arctotertiary elements that graduallybecame more significant. Some elements of these floras must haveadapted to the dry climates throughout the Miocene. As mentionedabove, during this period evergreen sclerophyllous–laurophyllousforests were of great importance in the vegetation of Iberia. It mayhave been in Iberia where species of the genera Pistacia and Ceratoniaevolved. The oldest recorded Pistacia are those of the Burdigalian ofCatalonia (Bessedik, 1985), while Ceratonia has a first appearance inthe Middle Miocene of Madrid Basin (Appendix A) and the south ofthe Peninsula (Jiménez-Moreno and Suc, 2007).

Other pre-Mediterranean elementsmay have been associatedwiththis evergreen laurophyllous vegetation, e.g., the ancestors of Quercusilex L. and Q. coccifera L. The former may have its origins in holm oaksassociated with lauroid elements such as Q. drymeja Ung. in the UpperMiocene of La Cerdaña (Barrón, 1996), Q. praeilex Sap. in the UpperMiocene of Ardèche (Saporta, 1879), and Q. praecursor Sap. et Mar. inthe Pliocene of Meximieux (Saporta and Marion, 1876). The idea thatQ. ilex should arise from this set of subtropical oaks is in agreementwith the area of distribution of the subspecies ilex in humid andsubhumid Mediterranean areas (Pons and Vernet, 1971).

Q. coccifera on the other hand appears to be related to fossil speciesthat developed in humid–mesic environments (Kvaček and Walther,1989) such as Q. mediterranea Ung. During the driest periods of theNeogene, this speciesmost likely sought refuge in lauroid formations. Inthe Iberian Peninsula, Q. mediterranea has been identified in theVallesian of the La Cerdaña Basin in association with mesophyllousand notophyllous taxa (Barrón, 1996). Similarly, the genus Neriumwasrelated to lauroid vegetation from the Palaeogene until the Pliocene(Saporta and Marion, 1876; Colom, 1983; Sanz de Siria, 1987).

As mentioned earlier, the first data onMediterranean-type environ-ments in the Iberian Peninsula came from palynological studies ofAragonian materials within the Duero Basin. Here the tree cover wasrepresented by Mediterranean woodland, which would have includedboth fluvial broadleaved ash and alder woods, and steppeland woodsand thickets dominated by Quercus (Rivas-Carballo, 1991).

From the Pliocene onwards, the eastern Peninsula saw anexpansion of Mediterranean-type taxa, many of which had Palaeo-tropical ancestors. Arctotertiary taxa that adapted to Mediterraneanclimatic conditions were also to be found, although in smallernumbers in megafloristic assemblages. Such was the case of Acerpseudomonspessulanum Ung., (Plate I, fig. 7) the remains of whichhave been found in the south of the Peninsula (Barrón et al., 2003).

Despite the disappearance of the laurel forests during the Pliocene,some of the species that belonged to them survived in refugia, and arenow found in areas that can provide for their specific temperature andwater requirements (Costa Tenorio et al., 2005). Such is the case ofLaurus nobilis L., Rhododendron ponticum L., Prunus lusitanica L., Myr-ica faya Ait. and different types of vascular cryptogams.

as outcrop, Rubielos de Mora Basin (E Spain),

d Sub-basin (C Spain);

, Lisbon Area (W Portugal);

Sub-basin (C Spain);

outcrop, Rubielos de Mora Basin (E Spain);

Fig. 10. Composite range chart of the main types of vegetation in the Iberian Peninsula along the Cenozoic. The appearance and disappearance time of these vegetation types isshown. Abbreviations: Dan—Danian, Se— Selandian, Tha— Thanetian, Y— Ypresian, Lu— Lutetian, Ba— Bartonian, Pri— Priabonian, Ru— Rupelian, Ch— Chattian, Aq— Aquitanian,Bur — Burdigalian, Lan — Langhian, Ser — Serravallian, Tor — Tortonian, Mes — Messinian, Zan — Zanclean, Pia — Piacenzian, Gel — Gelasian, E — Early Pleistocene, M — MiddlePleistocene, L — Late Pleistocene, H — Holocene.


Today, Macaronesia provides refugia for Palaeotropical broad-leaved evergreen vegetation. Species of Laurus, Ocotea, Persea,Notholaea, Prunus, Myrica, Myrsinaceae, etc., still co-occur, as theydid in the Iberian Peninsula during the Neogene. However, theseforests are impoverished with respect to certain typical Palaeotropicalcomponents such as the Magnoliaceae, Ebenaceae, the evergreenQuercus and different species of Arecaceae.

5. Conclusions

During most of the Cenozoic, the vegetation of the IberianPeninsula was characterised by Palaeotropical taxa that livedalongside Arctotertiary elements from the Oligocene onwards. Themain vegetational types through the Cenozoic were: tropical,evergreen xerophyllous (subtropical and Mediterranean sclerophyl-lous formations, leguminous communities), coniferous, laurel anddeciduous broad leaved forests, mangroves and non-forested lands(steppes or prairies) (Fig. 10).

During the Palaeocene and Eocene, tropical evergreen forestsdeveloped with Lauraceae, Fagaceae, Juglandaceae and Normapollesproducers, with ferns occupying the understory, forming a vegetationstyle similar to that of the late Cretaceous. From the Eocene onwards,mangroves including Nypa became important along the shores of theTethys Sea.

The cooling that occurred at the end of the Palaeogene led to thedevelopment of evergreen sclerophyllous forests, open woodland ofleguminous species, edaphically-mediated laurel forests and theappearance of Arctotertiary taxa during the Oligocene.

The laurel forests were of great importance in the landscapes of theCenozoic in Iberia. They may have replaced the territory's tropicalforests following the Late Eocene. Showing great ecological tolerancethey appeared in mountain ranges and near the sea. These forestswere the main generators of the taxa that comprise the modernIberian Mediterranean flora.

During the Miocene, the Arctotertiary vegetation survived thewarm, subtropical climate by retreating to the mountains or riparianareas where water (from the rain or in the ground) was in sufficientsupply. It may have competed with laurel forests to form ecotones inmountainous areas, although it was predominant in the Lower TagusBasin in the Middle and Upper Miocene.

Grasses became common from the Upper Burdigalian. Dependingon the water available, great prairies or steppes of Amaranthaceae–Chenopodiaceae, Poaceae and Asteraceae developed in the centre ofthe Peninsula during the Mid and Upper Miocene. The first signs ofMediterranean-type environments are reflected in small Quercus andCupressaceae woods that dotted the steppe of the Duero Basin duringthe Vallesian.

In Catalonia and Portugal, palynological studies have shown thatduring the Pliocene there was a progressive extinction of thermo-phyllous taxa and an increase in Mediterranean elements (evergreenQuercus, Olea, Ericaceae and Cistaceae). In the Lower Tagus Basin,open vegetation became predominant during the Gelasian.

Despite all data presented in this paper, the majority of theCenozoic Iberian basins have been not sufficiently studied from aPalaeobotanical point of view. In addition, there is less knowledgeconcerning Iberian Paleogene than Neogene. At present, thesedeficiencies impede a complete reconstruction of the vegetationalhistory during the Iberian Cenozoic.

Acknowledgements

This work was performed as part of the PALEODIVERSITAS I (CGL2006-02,956-BOS) and NECLIME research projects. We wish to thankDr. José Carrión (Editor) and the two anonymous referees whoprovided valuable suggestions for the improvement of themanuscript.We also sincerely thank Dr. Nuria Solé de Porta, Dr. Jorge Morales, Dr.Julio Gómez-Alba, Robert Raine and Adrian Burton for their help andkindness.


Appendix A. Supplementary data

Supplementary data associatedwith this article can be found in theonline version. doi:10.1016/j.revpalbo.2009.11.007.

References

Alcalá, B., Benda, L., Ivanovic Calzaga, Y., 1996. Erste palynologische Untersuchungenzur Altersstellung des Neogen-Beckens von Xinzo de Limia (Prov. Orense, Spanien).Newsl. Stratigr. 34, 31–38.

Alonso-Zarza, A.M., Armenteros, I., Braga, J.C., Muñoz, A., Pujalte, V., Ramos, E., Aguirre,J., Alonso-Gavilán, G., Arenas, C., Baceta, J.I., Carballeira, J., Calvo, J.P., Corrochano, A.,Fornós, J.J., González, A., Luzón, A., Martín, J.M., Pardo, G., Payros, A., Pérez, A.,Pomar, L., Rodríguez, J.M., Villena, J., 2002. Tertiary. In: Gibbons, W., Moreno, T.(Eds.), The Geology of Spain. Geol. Soc, London, pp. 293–334.

Alonso-Zarza, A.M., Calvo, J.P., Silva, P.G., Torres, T., 2004. Cuenca del Tajo. In: Vera, J.A.(Ed.), Geología de España. SGE-IGME, Madrid, pp. 556–561.

Álvarez Ramis, C., 1982. Sobre la presencia de una flora de paleomanglar en elPaleógeno de la depresión central catalana (curso medio del Llobregat). Acta Geol.Hisp. 17, 5–9.

Barrón, E., 1996. Estudio tafonómico y análisis paleoecológico de la macro y microfloramiocena de la cuenca de la Cerdaña. Ph.D. thesis. Univ. Complutense Madrid, Spain.

Barrón, E., 1999. Estudio macroflorístico del afloramiento mioceno de concrecionescarbonáticas de Izarra (Álava, España). Aspectos tafonómicos, paleoecológicos ybioestratigráficos. Rev. Esp. Paleontol. 14, 123–145.

Barrón, E., Comas-Rengifo, M.J., 2007. Differential accumulation of miospores in UpperMiocene sediments of the La Cerdaña basin (Eastern Pyrenees, Spain). CR Palevol 6,157–168.

Barrón, E., Diéguez, C., 2001. Estudio macroflorístico del Mioceno Inferior lacustre de laCuenca de Rubielos de Mora (Teruel, España). Bol. Geol. Min. 112 (2), 13–56.

Barrón, E., Diéguez, C., 2005. Cuticular study of leaf compressions from the UpperMiocene (Vallesian) diatomites of Cerdaña Basin (Eastern Pyrenees, Spain). N. Jb.Geol. Paläontol. Abh. 237, 61–85.

Barrón, E., Peyrot, D., 2006. La vegetación forestal en el Terciario. Paleoambientes ycambio climático. Fundación Séneca–Agencia de Ciencia y Tecnología de la Regiónde Murcia, Murcia, pp. 55–76.

Barrón, E., Muñiz, F., Mayoral, E., 2003. Aspectos macroflorísticos del Plioceno de Lepe(Cuenca del Guadalquivir, Huelva, España). Consideraciones paleoecológicas. Bol.R. Soc. Esp. Hist. Nat. (Sec. Geol.) 98, 91–109.

Barrón, E., Hernández, J.Mª., López-Horgue, M.A., Alcalde-Olivares, C., 2006a. Palaeoe-cology, biostratigraphy and palaeoclimatology of the lacustrine fossiliferous beds ofthe Izarra Formation (Lower Miocene, Basque–Cantabrian basin, Álava province,Spain) based on palynological analysis. Rev. Esp. Micropaleontol. 38, 321–338.

Barrón, E., Lassaletta, L., Alcalde-Olivares, C., 2006b. Changes in the Early Miocenepalynoflora and vegetation in the east of the Rubielos de Mora Basin (SE IberianRanges, Spain). N. Jb. Geol. Paläontol. Abh. 242 (2/3), 171–204.

Batten, D.J., 1981. Stratigraphic, palaeogeographic and evolutionary significance of LateCretaceous andearly TertiaryNormapollespollen. Rev. Palaeobot. Palynol. 35, 125–137.

Batten, D.J., 1999. Small palynomorphs. In: Jones, T.P., Rowe, N.P. (Eds.), Fossil Plantsand Spores: Modern Techniques. Geol. Soc, London, pp. 15–19.

Bessais, E., Cravatte, J., 1988. Les écosystèmes végétaux pliocènes de Catalogne Méridionale.Variations latitudinales dans le domaine Nord-OuestMéditerranéen. Geobios 21, 49–63.

Bessedik, M., 1985. Reconstitution des environments miocènes des règions nordouestméditerranéenes a partir de la palynologie. Ph.D. thesis. Univ. Montpellier II, France.

Bessedik, M., Cabrera, L., 1985. Le couple récif-mangrove à Sant Pau d'Ordal (Vallès-Pénédès, Espagne), témoin du maximum transgressif en Méditerranée nordoccidentale (Burdigalien supérieur–Langhien inférieur). Newsl. Stratigr. 14, 20–35.

Billups, K., Pälike, H., Channell, J.E.T., Zachos, J.C., Shackleton, N.J., 2004. Astronomiccalibration of the late Oligocene through early Miocene geomagnetic polarity timescale. Earth Planet. Sci. Lett. 224, 33–44.

Böhme,M., 2003. TheMiocene Climatic Optimum: evidence from ectothermic vertebratesof Central Europe. Palaeogeogr. Palaeoclimatol. Palaeoecol. 195, 389–401.

Calvo, J.P., 2004. Rasgos comunes de las cuencas cenozicas. In: Vera, J.A. (Ed.), Geologíade España. SGE-IGME, Madrid, pp. 584–586.

Calvo, J.P., Daams, R., Morales, J., López-Martínez, N., Agustí, J., Anadón, P., Armenteros,I., Cabrera, L., Civis, J., Corrochano, A., Díaz-Molina, M., Elizaga, E., Hoyos, M., Martín-Suárez, E., Martínez, J., Moissenet, E., Muñoz, A., Pérez-García, A., Pérez-González,A., Portero, J.M., Robles, F., de Santisteban, C., Torres, T., Van derMeulen, A.J., Vera, J.A.,Mein, P., 1993. Up-to-date Spanish continental Neogene synthesis and paleoclimaticinterpretation. Rev. Soc. Geol. Esp. 6 (3–4), 29–40.

Castro, L.N.S.P., 2006. Dinoflagelados e outros palinomorfos do Miocénico do sectordistal da Bacia do Baixo Tejo. Ph.D. thesis. Univ. Nova Lisboa, Portugal.

Cavagnetto, C., 2002. La palynoflore du Bassin d'As Pontes en Galice dans le Nord Ouestde l'Espagne à la limite Rupélien-Chattien (Oligocène). Palaeontogr. Abt. B 263,161–204.

Cavagnetto, C., Anadón, P., 1994. Une mangrove complexe dans le Bartonien du bassinde l' Ebre (NE de l' Espagne). Palaeontogr. Abt. B 236, 147–165.

Cavagnetto, C., Anadón, P., 1996. Preliminary palynological data on floristic and climaticchanges during the Middle Eocene–Early Oligocene of the eastern Ebro basin,northeast Spain. Rev. Palaeobot. Palynol. 92, 281–305.

Cavagnetto, C., Guinet, P., 1994. Pollen fossile de Leguminosae–Mimosoideae dansl'Oligocène inférieur de l'Ebre (Espagne)—implications paléoclimatiques etpaléogeographiques. Rev. Palaeobot. Palynol. 81, 327–335.

CIESM, 2008. The Messinian Salinity Crisis from mega-deposits to microbiology—aconsensus report nº 33. In: Briand, F. (Ed.), CIESMWorkshop Monographs, Monaco,p. 168.

Civis, J., 1977a. Los foraminíferos pliocénicos de Papiol (Barcelona). Significaciónpaleoecológica y paleogeográfica. Stvd. Geol. Salmant. 13, 7–30.

Civis, J., 1977b. Estudio de los foraminíferos pliocénicos de Can Albareda (Barcelona).Análisis paleoecológico y bioestratigráfico. Stvd. Geol. Salmant. 13, 105–126.

Civis, J., 2004. Cuencas cenozoicas: rasgos generales, estructuración. In: Vera, J.A. (Ed.),Geología de España. SGE-IGME, Madrid, pp. 531–533.

Colom, G., 1983. Los lagos del Oligoceno de Mallorca. Gràfiques Miramar S.A, Palma deMallorca. 166 pp.

Collinson, M.E., 1992. Vegetational and floristic changes around the Eocene/Oligoceneboundary in western and central Europe. In: Prothero, D.R., Berggren, W.A. (Eds.),Eocene–Oligocene Climatic and Biotic Evolution. Princeton Univ. Press, Princeton,pp. 437–450.

Collinson, M., Hooker, J.J., 2003. Paleogene vegetation of Eurasia: framework formammalian faunas. Deinsea 10, 41–83.

Costa Tenorio, M., Morla Juaristi, C., Sainz Hollero, H., 2005. Los bosques ibéricos: unainterpretación geobotánica, 4th ed. Ed. Planeta, Barcelona, p. 597.

Daams, R., Alcalá, L., Álvarez Sierra, M., Azanza, B., van Dam, J.A., van der Meulen, A.-J.,Morales, J., Nieto, M., Peláez-Campomanes, P., Soria, D., 1998. A stratigraphicalframework for Miocene (MN4–MN13) continental sediments of Central Spain. CRAcad. Sci. Paris Scien. Terre Planètes 327, 625–631.

Diniz, F., 1984a. Apports de la palynologie à la connaissance du Pliocène portugais. RioMaior, unbassinde réferencepour l'histoire de laflore, de la végétation et du climatdela façade atlantique de l'Europe meridionale. Ph.D. thesis. Univ. Montpellier, France.

Diniz, F., 1984a. Étude palynologique du bassin pliocène de Rio Maior (Portugal).Paléobiol. Cont. 14, 259–267.

Duke, N.C., Benzie, J.A.H., Goodall, J.A., Ballment, E.R., 1998. Genetic structure andevolution of species in the mangrove genus Avicennia (Avicenniaceae) in the Indo-West Pacific. Evolution 52 (6), 1612–1626.

Fauquette, S., Guiot, J., Suc, J.-P., 1998. A method for climatic reconstruction of theMediterranean Pliocene using pollen data. Palaeogeogr. Palaeoclimatol. Palaeoecol.144, 183–201.

Fauquette, S., Suc, J.-P., Guiot, J., Diniz, F., Feddi, N., Zheng, Z., Bessais, E., Drivaliari, A.,1999. Climate and biomes in the West Mediterranean area during the Pliocene.Palaeogeogr. Palaeoclimatol. Palaeoecol. 152, 15–36.

Fernández-Marrón, M.T., 1979. Essai de resolution de problemes stratigraphiques de lalimite Paleogene–Neogene par les études de macroflore. Ann. Geol. Pays Hellén.hors ser. fasc. 1, 403–412.

Fernández-Marrón, M.T., López-Martínez, N., Fonollá-Ocete, J.F., Valle-Hernández, M.F.,2004. The palynological record across the Cretaceous–Tertiary boundary indiffering palaeogeographical settings from the southern Pyrenees, Spain. In:Beaudoin, A.B., Head, M.J. (Eds.), The Palynology and Micropalaeontology ofBoundaries: Geol. Soc. London Spec. Publ., vol. 230, pp. 243–255.

García-Castellanos, D., Vergés, J., Gaspar-Escribano, J., Cloeting, S., 2003. Interplay betweentectonics, climate andfluvial transport during theCenozoic evolution of theEbrobasin(NE Iberia). J. Geophys. Res. 108 (B7), 2357. doi:10-1029/2002JB002073.

Gradstein, F.M., Ogg, J.G., Smith, A.G., Agterberg, F.P., Bleeker, W., Cooper, R.A., Davydov,V., Gibbard, P., Hinnov, L.A., House, M.R., Lourens, L., Luterbacher, H.-P., McArthur, J.,Melchin, M., J., Robb, L.J., Shergold, J., Villeneuve, M., Wardlaw, B.R., Ali, J., Brinkhuis,H., Hilgen, F.J., Hooker, J., Howarth, R.J., Knoll, A.H., Laskar, J., Monechi, S., Powell, J.,Plumb, K.A., Raffi, I., Röhl, U., Sanfilippo, A., Schmitz, B., Shackleton, N.J., Shields, G.A.,Strauss, H., van Dam, J., Veizer, J., van Kolfschoten, Th.,Wilson, D., 2004. Geologic TimeScale. Cambridge Univ. Press, Cambridge, p. 500.

Grimm, E.C., 2008. TILIA 1.0.1Illinois State Museum, Springfield, IL. http://intra.museum.state.il.us/pub/grimm/.

Hably, L., Fernández-Marrón, M.T., 1998. A comparison of the Oligocene floras of theTethyan and Central-Paratethyan areas on the basis of Spanish and Hungarianmacroflora. Tertiary Res. 18, 67–76.

Haseldonckx, P., 1973. The Palynology of some Paleogene deposits between the RioEsera and the Rio Segre, southern Pyrenees, Spain. Leidse. Geol. Meded. 49,145–165.

Jiménez-Moreno, G., Suc, J.-P., 2007. Middle Miocene latitudinal climatic gradient inWestern Europe: evidence from pollen records. Palaeogeogr. Palaeoclimatol.Palaeoecol. 253, 208–225.

Jiménez-Moreno, G., Fauquette, S., Suc, J.-P., Aziz, H.A., 2007. Early Miocene repetitivevegetation and climatic changes in the lacustrine deposits of the Rubielos de MoraBasin (Teruel, Spain). Palaeogeogr. Palaeoclimatol. Palaeoecol. 250, 101–113.

Jiménez-Moreno, G., Fauquette, S., Suc, J.-P., 2009. Miocene to Pliocene vegetationreconstruction and climate estimates in the Iberian Peninsula from pollen data.Rev. Palaeobot. Palynol. doi:10.1016/j.revpalbo.2009.08.001.

Knobloch, E., Kvaček, Z., Bužek, C., Mai, D.H., Batten, J.D., 1993. Evolutionary significanceof floristic changes in the Northern Hemisphere during the Late Cretaceous andPalaeogene, with particular reference to Central Europe. Rev. Palaeobot. Palynol. 78,41–54.

Kovar-Eder, J., Kvaček, Z., Martinetto, E., Roiron, P., 2006. Late Miocene to Early Pliocenevegetation of southern Europe (7–4 Ma) as reflected in the megafossil plant record.Palaeogeogr. Palaeoclimatol. Palaeoecol. 238, 321–339.

Kvaček, Z., 2005. Early Miocene records of Craigia (Malvaceae s.l.) in Most Basin, NorthBohemia—whole plant approach. J. Czech. Geol. Soc. 49, 161–171.

Kvaček, Z., 2007. Do extant nearest relatives of thermophile European Cenozoic plantelements reliably reflect climatic signal? Palaeogeogr. Palaeoclimatol. Palaeoecol.253, 32–40.

Kvaček, Z., Walther, H., 1989. Paleobotanical studies in Fagaceae of the EuropeanTertiary. Pl. Syst. Evol. 162, 213–229.

http://dx.doi.org/10-2002JB002073


Leroy, S.A.G., 1997. Climatic and non-climatic lake level changes inferred from a Plio–Pleistocene lacustrine complex of Catalonia (Spain): palynology of the Tres Pinssequence. J. Palaeolimnol. 17, 347–367.

Lisiecki, L.E., Raymo, M.E., 2005. A Pliocene–Pleistocene stack of 57 globally distributedbenthic δ18 O records. Paleoceanography 20, PA1003. doi:10.1029/2004PA001071.

Lisiecki, L.E., Raymo, M.E., 2007. Plio–Pleistocene climate evolution: trends andtransitions in glacial cycle dynamics. Quatern. Sci. Rev. 26, 56–69.

López-Martínez, N., 1989. Tendencias en Paleobiogeografía. El futuro de la biogeografíadel pasado. In: Aguirre, E. (Ed.), Paleontología, Nuevas tendencias 10. CSIC, Madrid,pp. 271–296.

López-Martínez, N., Fernández-Marrón, M.T., Valle-Hernández, M.F., 1999. Thesuccession of vertebrates and plants across the Cretaceous–Tertiary boundary inthe Tremp formation, Ager valley (South-central Pyrenees, Spain). Geobios 32,617–627.

Mai, D.H., 1989. Development and regional differentiation of the European vegetationduring the Tertiary. Pl. Syst. Evol. 162, 79–91.

Mai, D.H., 1991. Palaeofloristic changes in Europe and the confirmation of theArctotertiary–Palaeotropical geofloral concept. Rev. Palaeobot. Palynol. 68, 29–36.

Médus, J., 1965. L'évolution biostratigraphique d'une lagune néogène de Galicie(Espagne). Pollen Spores 7, 381–393.

Médus, J., 1970. Contribution a la connaissance des associations polliniques du Crétacéterminal dans le S–E de la France et leN.E. de l' Espagne. Rev.Micropaléontol. 13, 3–15.

Médus, J., 1972. Palynological zonation of the Upper Cretaceous in Southern France andNortheastern Spain. Rev. Palaeobot. Palynol. 14, 287–295.

Médus, J., 1977. Palynostratigraphie des zones a Alveolina primaeva A. laevis et A.cucumiformis dans le Pyrénées. Geobios 10, 625–639.

Médus, J., Colombo, F., 1991. Succession climatique et limite stratigraphique Crétacé–Tertiaire dans le N.E. de l' Espagne. Acta Geol. Hisp. 26, 173–179.

Médus, J., Feist, M., Rocchia, R., Batten, D.J., Boclet, D., Colombo, F., Tambareau, Y.,Villatte, J., 1988. Prospects for recognition of the palynological Cretaceous/Tertiaryboundary and an iridium anomaly in nonmarine facies of the eastern SpanishPyrenees: a preliminary report. Newsl. Stratigr. 18, 123–138.

Médus, J., Colombo, F., Durand, J.P., 1992. Pollen and spore assemblages of theuppermost Cretaceous continental formations of south-eastern France and north-eastern Spain. Cretaceous Res. 13, 119–132.

Miller, K.G., Wright, J.D., Fairbanks, R.G., 1991. Unlocking the ice house: Oligocene–Miocene oxygen isotopes, eustasy, and margin erosion. J. Geophys. Res. 96 (B4),6829–6848.

Mosbrugger, V., Utescher, T., 1997. The coexistence approach—a method forquantitative reconstructions of Tertiary terrestrial paleoclimate data using plantfossils. Palaeogeogr. Palaeoclimatol. Palaeoecol. 134, 61–86.

Mosbrugger, V., Utescher, T., Dilcher, D., 2005. Cenozoic continental climatic evolutionof Central Europe. Proc. Nat. Acad. Sci. USA 102, 14964–14969.

Nichols, D.J., Johnson, K.R., 2008. Plants and the K–T Boundary. Cambridge Univ, Press,Cambridge. 280 pp.

Nichols, D.J., Fleming, R.F., Frederiksen, N.O., 1990. Palynological evidence of effects ofthe terminal Cretaceous event on terrestrial floras in Western North America. In:Kauffman, E.J., Walliser, O.H. (Eds.), Extinction Events in Earth History. Springer-Verlag, Berlin, pp. 351–364.

Pais, J., 1981. Contribuição para o conhecimento da vegetação Miocénica da parteocidental da Bacia do Tejo. Ph.D. thesis. Univ. Nova Lisboa, Portugal.

Pais, J., 1986. Évolution de la végétation et du climat pendant le Miocène au Portugal.Ciênc. Terra (UNL) 8, 179–191.

Pais, J., 1992. Contributions to the Eocene paleontology and stratigraphy of Beira Alta,Portugal. III—Eocene plant remains from Naia and Sobreda (Beira Alta, Portugal).Ciênc. Terra (UNL) 11, 91–108.

Pais, J., 2004. The Neogene of the Lower Tagus Basin (Portugal). Rev. Esp. Paleontol. 19,229–242.

Pais, J., Cunha, P.P., Legoinha, P., 2009. Uma proposta litostratigráfica para o Cenozóicode Portugal. Livro branco da Geologia de Portugal, APG, Lisboa.

Pais, J., Castro, L., Vieira, M., Barrón, E., in press. Miocene and Pliocene plants fromPortugal and paleoclimates. Mem. Acad. Ciên. Lisboa, Class. Ciên. 43.

Palamarev, E., 1989. Paleobotanical evidences of the Tertiary history and origin of theMediterranean sclerophyll dendroflora. Pl. Syst. Evol. 162, 93–107.

Pardo, G., Arenas, C., González, A., Luzón, A., Muñoz, A., Pérez, A., Perez-Ribarés, F.J.,Vázquez-Urbez, M., Villena, J., 2004. La cuenca del Ebro. In: Vera, J.A. (Ed.), Geologíade España. SGE-IGME, Madrid, pp. 533–543.

Paul, H.A., Zachos, J.C., Flower, B.P., Tripati, A., 2000. Orbitally induced climate andgeochemical variability across the Oligocene/Miocene boundary. Paleoceanogra-phy 15, 471–485.

Peñalba, C., 1985. Estudio esporopolínico del Neógeno occidental de la Cuenca delGuadalquivir. M.Sc. thesis. Univ, Salamanca, Spain.

Peñalver, E., 2002. Los insectos dípteros del Mioceno del Este de la Península Ibérica;Rubielos de Mora, Ribesalbes y Bicorp. Tafonomía y Sistemática. Ph.D. thesis. Univ.València, Spain.

Pons, A., Vernet, J.-L., 1971. Une synthèse nouvelle de l'histoire du Chêne vert (Quercusilex L.). Bull. Soc. Bot. Fr. 118, 841–850.

de Porta, J., Kedves, M., de Porta, Solé, Civis, J., 1985. Palinología del Maastrichtiense delBarranco de la Posa (Lérida, España). Problemática regional. Rev. Inv. Geol. 40, 5–28.

Portero, J.M., Aznar, J.M., 1984. Evolución morfotectónica y sedimentación terciarias enel Sistema Central y cuencas limítrofes (Duero y Tajo). I Congr. Esp. Geol., Segovia,vol. 3, pp. 253–264.

Postigo-Mijarra, J.M., Barrón, E., Manzaneque, F., Morla, C., 2009. Floristic changes in theIberian Peninsula and Balearic Islands during the Cenozoic. J. Biogeogr. 36 (11),2025–2043.

Rivas-Carballo, M.R., 1991. The development of vegetation and climate during theMiocene in the south-eastern sector of the Duero Basin (Spain). Rev. Palaeobot.Palynol. 67, 341–351.

Rivas-Carballo, M.R., 2007. Informe palinológico del Proyecto de Soterramiento de la M-30 (Proyecto “Madrid Río”). Obras de mejora en la red de saneamiento. Technicalreport, Área Soc. Coop., Madrid (ined.).

Rivas-Carballo, M.R., Valle-Hernández, M., 2004. Análisis palinológico del Terciario(Mioceno) y Cuaternario de Madrid (Cuenca de Madrid). Libro Resúmenes XXJornadas Soc. Esp. Paleontol, p. 155.

Rivas-Carballo, M.R., Alonso-Gavilán, G., Valle-Hernández, M., Civis, J., 1994. Miocenepalynology of the central sector of the Duero basin (Spain) in relation topalaeogeography and palaeoenvironment. Rev. Palaeobot. Palynol. 82, 251–264.

Roiron, P., 1983. Nouvelle étude de la macroflore plio–pléistocene de Crespià(Catalogne, Espagne). Geobios 16, 687–715.

Sanz de Siria, A., 1987. Datos para el conocimiento de las floras pliocénicas de Cataluña.Paleontol. Evol. 21, 295–303.

Sanz de Siria, A., 1992. Estudio de la macroflora oligocena de las cercanías de Cervera(colección Martí Madern del Museo de Geología de Barcelona). Treb. Mus. Geol.Barcelona 2, 269–379.

Sanz de Siria, A., 1994. La evolución de las paleofloras en las cuencas cenozoicascatalanas. Acta Geol. Hisp. 29, 169–189.

Sanz de Siria, A., 1996. Estudio paleoeológico y paleoclimático de la macrofloraoligocena de Cervera (Lleida, España). Treb. Mus. Geol. Barcelona 5, 143–170.

Saporta, G. de, 1879. Le monde des plantes avant l'apparition de l'homme. LibrairieAcad. Méd, Paris. 146 pp.

Saporta, G. de, Marion, A.-F., 1876. Recherches sur les végétaux fossiles de Meximieux.Arch. Mus. Hist. Nat. Lyon 1, 131–335.

Singh, G., 1988. History of arid land vegetation and climate—a global perspective. Biol.Rev. 63, 159–195.

Sitter, L.U., 1961. La phase tectogénétique pyrénéenne dans les Pyrénées meridionales.CR Soc. Géol. Fr. 8, 224–225.

Solé de Porta, N., de Porta, J., 1977. Primeros datos palinológicos del Messiniense(=Turoliense)deArenasdelRey (Provincia deGranada). Stvd.Geol. Salmant. 13, 67–88.

Solé de Porta, N., de Porta, J., 1984. État actuel des connaissances palynologiques duTertiaire de l'Espagne: Rev Paléobiol. vol. esp. , pp. 209–219.

Solé de Porta, N., Jaramillo, C.A., Martín-Algarra, A., 2007. Pantropical palynomorphs inthe Eocene of the Malaguides (Betic range, southern Spain). Rev. Esp. Micro-paleontol. 39, 189–204.

Suc, J.-P., Cravatte, J.-P., 1982. Étude palynologique du Pliocène de Catalogne (nord-estde l' Espagne). Paléobiol. Cont. 13, 1–31.

Suc, J.-P., Fauquette, S., Bessedik,M., Bertini, A., Zheng, Z., Clauzon, G., Suballyová, D., Diniz,F., Quézel, P., Feddi, N., Clet, M., Bessais, E., Taoufiq, N.B., Méon, H., Combourieu-Nebout, N., 1999. Neogene vegetation changes in West European and West circum-Mediterranean areas. In: Agustí, J., Rook, L., Andrews, P. (Eds.), Hominoid Evolutionand Climatic Change in Europe, vol. 1. Cambridge Univ. Press, pp. 378–388.

Tiffney, B.H., Manchester, S., 2001. The use of geological and paleontological evidence inevaluating plant phytogeographic hypotheses in the northern hemisphere Tertiary.Int. J. Plant Sci. 162 (6 suppl.), 3–17.

Utescher, T., Mosbrugger, V., 2007. Eocene vegetation patterns reconstructed from plantdiversity—aglobal perspective. Palaeogeogr. Palaeoclimatol. Palaeoecol. 247, 243–271.

Utescher, T., Erdei, B., François, L., Mosbrugger, V., 2007. Tree diversity in the Mioceneforest of western Eurasia. Palaeogeogr. Palaeoclimatol. Palaeoecol. 253, 226–250.

Valle-Hernández, M., 1982. Estudio palinológico del Plioceno del NE de España. Ph.D.thesis. Univ. Salamanca, Spain.

Valle-Hernández, M., 1983. Nuevas aportaciones palinológicas al Plioceno de CanAlbareda (Barcelona). Stvd. Geol. Salmant. 19, 151–159.

Valle-Hernández, M.F., Peñalba, C., 1987. Aspectos palinológicos en el Neógeno delSuroeste de España. In: Civis, J. (Ed.), Paleontología del Neógeno de Huelva (W.Cuenca del Guadalquivir). Univ. Salamanca, pp. 153–157.

Valle-Hernández, M.F., Alonso-Gavilán, G., Rivas-Carballo, M.R., 1995. Analysepréliminaire du Miocène dans le NE de la Dépression du Duero (aire de Belorado,Burgos, España). Geobios 28, 407–412.

Valle-Hernández, M.F., Rivas-Carballo, M.R., Alonso-Gavilán, G., 2006. Síntesis de lavegetación y clima durante elMioceno en la cuencadel Duero. Geo-Temas9, 213–217.

Van Campo, E., 1989. Flore pollinique du Miocene Supérieur de Venta del Moro(Espagne). Acta Palynol. 1, 9–32.

Vázquez-Urbez, M., Arenas, C., Pardo, G., 2003. Análisis isotópico (δ13C y δ18O) de losdepósitos carbonatados del sector Borja-Tarazona: registro de cambio paleogeo-gráfico en el Mioceno de la cuenca del Ebro. Geo-temas 5, 237–241.

Vieira, M.C., 2009. Palinologia do Pliocénico da Orla Ocidental Norte e Centro dePortugal: Contributo para a compreensão da cronostratigrafia e da evoluçãopaleoambiental. Ph.D. thesis. Univ. Minho, Braga, Portugal.

Wolfe, J.A., 1978. A paleobotanical interpretation of Tertiary climates in the NorthernHemisphere. Amer. Scien. 66, 694–703.

Wolfe, J.A., 1979. Temperature parameters of humid tomesic forests of Eastern Asia andrelation to forests of other regions of the Northern Hemisphere and Australasia. USGeol. Surv. Prof. Pap. 1106, 1–37.

Wolfe, J.A., 1992. Climatic, floristic, and vegetational changes near the Eocene/Oligocene boundary in North America. In: Prothero, D.R., Berggren, W.A. (Eds.),Eocene–Oligocene Climatic and Biotic Evolution. Princeton Univ. Press, Princeton,pp. 421–436.

Wolfe, J.A., Upchurch Jr., G.R., 1986. Vegetation, climatic and floral changes at theCretaceous–Tertiary boundary. Nature 324, 148–152.

Zachos, J., Pagani, M., Sloan, L., Thomas, E., Billups, K., 2001. Trends, rhythms, andaberrations in global climate 65 Ma to Present. Science 292, 686–693.

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the cenozoic vegetation of the iberian peninsula: a synthesis

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