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A charophyte assemblage including Latochara tenuicostata (PECK 1937) and Mesochara gr. voluta (PECK 1937) was found in the Lower Tithonian bone-bed 148 of the stratigraphic section at the Pointe de Chassiron, Oléron Island (Charente-Maritime, Southwestern France). This bed, which is well known for its rich and diverse fauna of tetrapods, was deposited in a margino-littoral environment of Purbeckian facies in the Late Jurassic Charente palaeogulf. The occurrence of Latochara at Oléron Island is the most southern location known in the distribution of this genus during the Late Jurassic. This suggests that the boundary between the charophyte Boreal and Tethyan provinces, defined on the basis of this distribution, is not solely determined by latitudinal (i.e. thermal) factors. Ecological factors such as salinity and competition with other charophyte families are hypothesized as alternative explanations. [ABSTRACT FROM AUTHOR]

The Purbeckian facies of the northern margin of the Aquitaine Basin is exposed in the Cherves-de-Cognac section (SW France), considered as basal Cretaceous in age. Two lithological units have been identified. The basal unit (U1) is composed of an alternation of gypsum and finely bedded black dolomitic marlstone, occasionally stromatolitic in nature. It represents mostly hypersaline, dolomitic tidal flat, lagoonal, and sabkha-type environments. The upper unit (U2) consists of variably fossiliferous limestone-marl alternations that contain a diverse fauna and flora. In the upper part of this unit, a 4-m-thick level has yielded a rich vertebrate fauna. The preservational quality of the vertebrate fossils varies within the section. On the basis of faunal, floral, sedimentological and mineralogical information the vertebrate remains accumulated in brackish water environments in which the influence of freshwater has progressively increased towards the top of the section. The close association of environments representing varying degrees of marine and continental influence suggest an estuarine setting. [ABSTRACT FROM AUTHOR]

The taphonomy is a powerful and requisite tool for environmental reconstructions of ancient plant communities. Necrobiotic processes, which lead to the production of plant fragments, inform us on fossil plant physiology. Among the processes that can be drawn from necrobiotic studies is the retention of leaf organs on plants, the relative quantity of pollen grains produced by different fossil species or the significance of wildfire dynamics in ancient plant communities. Biostratinomy examination is a fundamental tool for elucidating fossil plant habitats. Numerous experimental data allow paleobotanists for evaluating the role of transport in the origin of fossil assemblages. Autochthonous plant assemblages, which are characterised by the preservation of fossil rooting structures, are relatively rare in the nature. In consequence, the search for palaeoecological information from parautochthonous to allochthonous assemblages has been a priority in taphonomy. As a result, taphonomic models have been elaborated in well-known sedimentological contexts, such as small lacustrine deltas, which allow for the distinction between riparian or perideltaic plant remains. Lithospheric processes modify plant debris after burial. The differences in the degrees of transformations (or alterations) during the diagenesis provide for information about the original morphology and biochemical composition of the plant tissues, which are also paleoecologically useful. Thus, amber diagenesis modifies resin biochemistry into new molecules that are still informative from the chemotaxonomical point of view. [Copyright &y& Elsevier]

Vegetative plant remains and microsporangiate cones, related to the fossil genera Frenelopsis and Classostrobus respectively, were studied in three localities from the Lower Cretaceous of the Pyrenees and Iberian Ranges (Spain). Sterile remains belong to three different species: F. Rubiesensis Barale, F. Ugnaensis sp. nov. and F. Turolensis sp. nov. The male cones Classostrobus ugnaensis sp. nov. and C. Turolensis sp. nov. are associated with the two latter species respectively, and C. Turolensis is found in connection with F. Turolensis . Internodes of F. Ugnaensis display small hemispherical papillae and long conical hairs covering the entire cuticle surface, while F. Turolensis has a strip of hairs near the leaf margin, in addition to more massive outer stomatal papillae and higher stomatal density. The tiny cones of C. Ugnaensis bear microsporophyll cuticles capped with vermiculate flattened papillae and a fringe of marginal hairs, while C. Turolensis has a central area of microsporophylls covered by long conical hairs. Sedimentological and taphonomic analyses show that the assemblages studied belong to a wide spectrum of habitats. These indicate that Spanish Lower Cretaceous frenelopsids were xeromorphic plants, able to adapt to helophytic and riparian habitats, and grew in brackish coastal marshes and fluvio–lacustrine freshwater environments. [ABSTRACT FROM AUTHOR]

Eleven boreholes and one outcrop of the Lower Cretaceous in South Dobrogea (south-eastern Romania) were sampled for charophytes. Twenty species are described and illustrated in two non-marine rock units, the Zăvoaia Member and the Gherghina Formation. The Zăvoaia Member contains a charophyte assemblage dominated by Feistiella bijuescensis , aff. Mesochara harrisii, Nodosoclavator bradleyi , Clavator bilateralis, and Clavator grovesii var. grovesii, indicating a Berriasian age. Other less abundant species include Feistiella sp., Latochara sp. , Mesochara dobrogeica sp. nov., Globator maillardii var. nurrensis , Atopochara trivolvis var. micrandra , Clavator grovesii var. discordis , Hemiclavator adnatus, and Hemiclavator neimongolensis var. posticecaptus. The occurrence of G. maillardii var. nurrensis in this assemblage suggests late Berriasian age. The Gherghina Formation is dominated by the species Atopochara trivolvis var. triquetra and Clavator grovesii var. jiuquanensis. Other less abundant species include Sphaerochara andersonii , aff. Mesochara harrisii , Globator maillardii var. trochiliscoides , Globator maillardii var. biutricularis , Clavator harrisii var. reyi, and Clavator ampullaceus var. latibracteatus var. nov. This assemblage indicates a late Barremian–early Aptian age. This study sheds new light on the palaeobiogeographical distribution of Lower Cretaceous charophytes in the Tethyan realm. Well-known western European charophyte species such as F. bijuescensis , S. andersonii , G. maillardii var. trochiliscoides , H. adnatus, and H. neimongolensis var. posticecaptus are herein described for the first time in eastern Europe. Very significantly, this is the first report in Europe of the hitherto North American taxon C. bilateralis , while the species C. ampullaceus has previously been reported only from the Middle East and eastern Africa. • Charophytes from the Amara and Gherghina formations (South Dobrogea) are described. • The Zăvoaia Member charophytes indicates a late Berriasian age. • Charophytes from the Gherghina Formation indicate an upper Barremian–lower Aptian age. • Well-known west European charophyte species are here described for the first. • First report in Europe of the so far middle eastern taxon Clavator ampullaceus. [ABSTRACT FROM AUTHOR]

A combined micropalaeontological, taphonomical and sedimentological study was carried out in the non-marine Barremian of the Maestrat Basin (E Iberian Chain) to elucidate the palaeoecology of Barremian charophytes. Understanding the palaeoecology of fossil charophytes is of prime importance for the accurate application of charophyte biozonations, since most species used as biostratigraphic markers and/or biozone index species are restricted to facies formed in a particular environment. Five charophyte biocoenoses were distinguished. (1) Charophyte association from freshwater alkaline lakes receiving low clastic input, mainly composed of Atopochara trivolvis var. triquetra, Clavator harrisii, Ascidiella stellata, and A. triquetra. The thalli known as Munieria grambastii, corresponding to Clavator utricles, were extremely abundant in the shallowest facies of the lake margins, and Hemiclavator-rich populations were also locally dominant. (2) An association characteristic of freshwater alkaline lakes with high clastic input was mainly composed of Echinochara lazarii, Globator maillardii var. trochiliscoides, A. trivolvis var. triquetra, C. harrisii, Hemiclavator neimongolensis var. neimongolensis, and locally also Clavator calcitrapus. (3) Monospecific populations of Porochara maestratica thrived in brackish settings with little clastic influence, whereas (4) monospecific E. lazarii populations thrived in clastic-influenced brackish settings. (5) A charophyte association grew in lakes that developed in mudflat to floodplain environments and was mainly constituted by E. lazarii, A. trivolvis var. triquetra, and C. harrisii var. harrisii and var. reyi. Accordingly, the palaeoenvironmental conditions inferred indicate that most of the charophyte species were controlled by (i) bathymetry, (ii) clastic content in the sedimentary environment and (iii) salinity. The stratigraphic succession studied shows an upwards increase in clastic content from the base to the top, which is associated with the more humid period recorded along the margins of the Tethys and the Boreal realm during the early Barremian–early late Barremian. In consequence, those species restricted to clastic-poor settings are constrained to the lower part of the section, whereas those taxa that were able to thrive in clastic-rich settings persisted throughout the entire section. This observation establishes a link between the changes observed in the charophyte floras recognized and the environmental changes that occurred during the Barremian in western Europe. [ABSTRACT FROM AUTHOR]

A lower and upper Barremian 690 m-thick succession composed of freshwater and brackish limestones, marls and clays was measured and sampled in the Maestrat Basin, Eastern Iberian Chain (Castelló, Spain). Thirty-three taxa were identified from charophyte fructifications and thalli, belonging to the three families that coexisted during the Early Cretaceous, i.e. Porocharaceae, Characeae and Clavatoraceae. Up to 25 different Clavatoraceae utricles were identified. This high species richness of clavatoraceans has not been observed elsewhere and sheds light on the role of Iberia, and particularly the Maestrat Basin, as a diversity hotspot for this family during the Barremian. Several of them have been taxonomically revisited, as regards both utricles and thalli. The Echinochara lazarii utricle is reinterpreted as showing bilateral rather than triradial symmetry. Anagenetic evolution within Clavator calcitrapus has been documented and has enabled us to distinguish between two varieties linked by intermediate morphotypes of biostratigraphic and palaeobiogeographic interest. The taxon Clavator grovesii var. jiuquanensis is reported for the first time in the Iberian Chain and in Spain. The structure of Charaxis spicatus is revisited and a new type of cortication is defined, called the double triplostichous cortication, which is unknown in either fossil or extant charophytes. This thallus is found in anatomical connection with Echinochara lazarii utricles, enabling a whole-plant reconstruction of the Echinochara plant. Lastly, new characters were found in Munieria grambastii thalli that confirm the membership of genus Munieria to the clavatoracean charophytes, particularly the calcification pattern of the internodal cell, which recalls that of clavatoroid utricles. • The most diverse clavatoracean flora (25 species) is described from the Iberian Chain. • A new gradualistic evolutionary lineage is shown for Clavator calcitrapus. • The whole plant Echinochara is reconstructed based on attached utricles and thalli. • Double triplostichous cortication, a new type of charophyte cortication is defined. • Internodal calcification of Munieria pinpoints its ascription to the Clavatoraceae [ABSTRACT FROM AUTHOR]

Abstract Rhus asymmetrica sp. nov. from the lower Oligocene of Cervera (Catalonia, Spain) is characterized by a trifoliate leaf with a symmetric sessile apical leaflet and asymmetric lateral leaflets. The apical leaflet displays a serrate margin and decurrent base with pinnate primary venation, craspedodromous secondary venation and an irregular reticulate tertiary framework. The lateral leaflets show a rounded base with a secondary basal vein in the distal part of the lamina, while the proximal part is straight or concave. Formerly, these specimens were accommodated within Rhus pyrrhae Unger. However, detailed study of the R. pyrrhae holotype has led us to emend its diagnosis to include its brochidodromous secondary venation pattern, which differs clearly from the venation pattern of the new species. Additionally, a number of leaf morphotypes from the Cervera palaeobotanical site that were erroneously attributed to Rhus by former authors have been segregated and related to Acer and Toxicodendron. The extant species R. aromatica displays the closest foliar structure to R. asymmetrica sp. nov. However, differences in the leaf morphology suggest that the new species grew under distinct palaeoclimatic conditions: (1) R. asymmetrica sp. nov. bears glands at the tips of the teeth of the lateral leaflets while R. aromatica is devoid of these glands. This character would help to prevent excessive evapotranspiration; (2) lateral leaflets of R. asymmetrica sp. nov. are asymmetric while in R. aromatica they are symmetric, suggesting that R. asymmetrica sp. nov. grew under a greater environmental stress than R. aromatica ; (3) R. asymmetrica sp. nov. displays fewer teeth with a larger tooth-area than R. aromatica. This would indicate growth under a warm climate with low seasonal contrast. These features are compatible with an open woodland habitat under subtropical palaeoclimatic conditions. Highlights • Rhus asymmetrica sp. nov. from the Oligocene of the Iberian Peninsula is described. • Living North American R. aromatica displays the leaf closest to R. asymmetrica. • Differences in leaf characters of R. asymmetrica and its NLR are climate-sensitive. • Glands in lateral leaflets teeth of R. asymmetrica point out to water stress. • R. asymmetrica shows few and large teeth as a response to warm and arid climate. [ABSTRACT FROM AUTHOR]

A diverse charophyte assemblage from the Middle Miocene of the Vallès‒Penedès and Vilanova basins (Catalonia, NE Spain) is here described and illustrated for the first time. This flora has been recovered from three localities: els Casots (Subirats), Vilobí del Penedès, and Mas de l´Alonso‒el Pi Gros (Vilanova i La Geltrú). The charophyte assemblages comprise ten different species distributed among three distinctive aquatic environments, and are approximately simultaneous to major fossil vertebrate sites of these basins. Sphaerochara ulmensis, Chara cf. vulgaris, Chara molassica var. notata, Lychnothamnus barbatus var. antiquus, Lychnothamnus sp., Nitellopsis (Tectochara) merianii, and Nitellopsis sp. occur associated to abraded benthic foraminifera in organic-rich claystones related to palustrine and shallow freshwater coastal lakes. Lamprothamnium papulosum forms monospecific assemblages in gypsum-claystone alternations attributed to a coastal brackish water salina. Chara cf. hispida and Chara sp. are found to be associated with ostracods in marls and limestones related to a permanent oligohaline and alkaline lake. The discovery of this aquatic flora sheds new light on the palaeoenvironmental conditions that prevailed in the Vallès‒Penedès Basin during the Langhian in the context of the Mid-Miocene Climatic Optimum and in the Vilanova Basin during the Serravallian. [ABSTRACT FROM AUTHOR]

The Pennsylvanian flora from the intramontane Erillcastell Basin in the eastern Pyrenees (Catalonia, Spain) is described in a palaeoenvironmental context based on a combined study of sedimentology, plant taphonomy and paleoecology. This basin differs from other Pyrenean basins of this age in comprising a wide array of fluvial channel and floodplain-related facies, with a limited development of peat mire facies. Both late Moscovian and early Ghzelian successions are rich in diverse calamitalean remains (mainly Calamites cistii and C. suckowii, in addition to C. undulatus in the Moscovian) and pecopterid foliage (mainly Polymorphopteris polymorpha) corresponding to marattialean tree ferns. An unusual feature of the fluvial channel assemblages is the common occurrence of arborescent lycopsids, especially Sigillaria brardii , in association with Calamites species, which presumably occupied riparian niches. Palaeotopographic, drainage and climatic constraints of the Erillcastell Basin may explain this unusual ecological distribution of Sigillaria brardii , which is mostly associated with peat mires and oxbow lakes in other coeval intramontane South European basins. Findings improve knowledge of intermontane forest ecosystems during the Middle to Late Pennsylvanian transition. • The Pyrenean Carboniferous units were recognized at Erillcastell Basin due to flora. • Moscovian riparian vegetation was composed of Sphenopsids and Sigillaria. • Gzhelian plant-taxa from the Erillcastell resembles to other European basins. • Particular plant distribution is recognized in the Gzhelian deposits from Erillcastell. • Sigillaria explored new palaeoecological niches in a regressive phase of its evolution. [ABSTRACT FROM AUTHOR]

Els Casots is one of the richest fossil vertebrate sites of the Vallès-Penedès Basin (Catalonia, Spain). It was discovered in 1989 and excavated briefly during the 1990s, resulting in the recovery of thousands of remains and the erection of several new mammal species. Excavations were resumed in 2018 and continue to date. Here we provide updated results regarding the age, stratigraphy, biota and palaeoenvironment of the site. The age of the site is well constrained to ~15.9 Ma thanks to recent bio- and magnetostratigraphic data, thus coinciding with the Miocene Climatic Optimum (MCO). The stratigraphic succession at the site area indicates lacustrine to palustrine environments with cyclically oscillating water level. There are several fossiliferous layers that have yielded a vertebrate fauna comprising up to 75 different vertebrate species including amphibians, reptiles, birds and mostly mammals. The finding of several articulated partial skeletons indicate that the site records an autochthonous to parautochthonous assemblage. The abundance and completeness of the vertebrate remains together with a well-constrained age and detailed stratigraphic and palaeoenvironmental data, make els Casots a key site for understanding wetland ecosystems in southern Europe during the MCO. [ABSTRACT FROM AUTHOR]

The analysis of depositional environments associated with sauropod dinosaurs has been revealed as a key element for assessing their palaeoecology. A detailed study of the sedimentology, plant taphofacies and titanosaur ichnology at the Fumanya localities (early Maastrichtian, Catalonia) reveals that two distinct palaeoenvironments existed within the coastal wetlands. These settings are correlated with the occurrence of two distinct track and plant remains distributions, which correspond to a) a marginal brackish lagoon environment where no vegetation grew and titanosaurs roamed, during a short time span, without apparently any preferential purpose, and b) a freshwater swamp area around charophyte lakes with evidence of vegetation growth (charophytes, palms, and probably ferns and cheirolepidiacean conifers) where titanosaurs congregated and fed actively during a long time span. These data indicate that titanosaurs trampled the muddy substrates of freshwater wetlands in order to forage according to the availability of plants. [ABSTRACT FROM AUTHOR]

Abstract: At the end of the 1970s, several lower Maastrichtian localities with plant megafossil remains were reported near the village of Isona in the Tremp Syncline of the southeastern Pyrenees. These assemblages include conifers (taxodioids and cheirolepidiaceans), monocot angiosperms (Sabalites palms and likely Pandanaceans) and at least 15 types of magnoliid and eudicot angiosperm leaves. Conifers, Sabalites palms and some eudicots are shared with coeval localities in Portugal, France, Austria and Romania. In addition, Sabalites palms and at least five types of magnoliids and eudicots found here are very similar to fossil leaves reported from Upper Cretaceous localities in North America, suggesting that the Isona flora possibly share some elements with North American floras. Data from the Isona locality also indicate that eudicots dominated the floodplain plant associations in fully continental-influenced terrestrial environments. [Copyright &y& Elsevier]

Abstract: Fragmented leaf laminas were the only organ known of the fossil palms Sabalites longirhachis (Unger) J. Kvaček et Herman. Recently, isolated leaves of S. longirhachis, palm logs and rooting systems have been found associated in Fumanya, a new Maastrichtian locality from the Southern Pyrenees. This has allowed proposing a taphonomy-based hypothesis of the habit and paleoecology of these extinct palms. Fossil leaves are represented by complete laminas bearing petioles attached. Leaves and logs are parautochthonous at the base of the first coal seam of the stratigraphic succession. Rooting systems provide evidence for autochthony in coal layers formed at the top of lacustrine limestones. The tree bearing S. longirhachis leaves is reconstructed as relatively slender, of up to 14m high, showing a smooth trunk with adventitious roots at the base and a crown keeping the marcescent leaves attached. The rooting system consisted of straight radial rootlets of about 1.5m in total diameter. Taphonomic and facies analyses carried out in Fumanya suggest that the habitats colonized by this species were small peat mires at the lakeshores of freshwater alkaline lakes. [ABSTRACT FROM AUTHOR]

We analyse the late Miocene (early Tortonian) climate of the La Cerdanya Basin (Catalonia, Spain) using the Climate Leaf Analysis Multivariate Program (CLAMP) based on an assemblage comprising twenty-nine dicot leaf taxa. Results show a mean annual temperature of 11.4 ± 2.1 °C. The coldest mean monthly temperature was 1.8 ± 3.4 °C while the warmest was 21.6 ± 2.5 °C. Growing season was 6.8 ± 1.1 months in duration. Precipitation during this period was 1082 ± 317 mm, reaching 661 ± 38 mm in the three wettest consecutive months, while in the three driest months it was 194 ± 229 mm. These results indicate a permanently humid temperate climate, with warm and wet summers. Compared with published palaeoclimatic results obtained using the Coexistence Approach method, our CLAMP analysis indicates lower temperatures and higher rainfall during the driest month. The climatic parameters are consistent with the occurrence of a temperate mixed evergreen and broadleaf deciduous fossil assemblage in the late Miocene of the La Cerdanya Basin. The assemblage contains more taxa in common with coeval localities from northern and central Europe than with Mediterranean sites; its closest modern analogue is with the montane flora from Honshu Island (Japan). Palaeoaltitudinal estimation using the terrestrial lapse rate method suggests that the La Cerdanya Basin was positioned at 1100–1550 m during early Tortonian times. These results challenge previous palynological and isotopic studies that inferred a palaeoaltitude of c. 600 m in early Tortonian-Messinian times. • The late Miocene (Tortonian) climate of La Cerdanya (Spain) is inferred using CLAMP. • Palaeoclimate was humid temperate, with warm summers, similar to coeval sites in Central Europe. • Montane floras and climate from Honshu Island, Japan comprise a good modern analogue. • La Cerdanya (eastern Pyrenees) was at 1100–1550 m a.s.l in the late Miocene similar to its present altitude. [ABSTRACT FROM AUTHOR]

The Eocene–Oligocene transition (EOT) climatic turnover is modelled in the Ebro Basin using CLAMP and analysing the Sarral (Priabonian) and the Cervera (Rupelian) floras. The results show a drop of temperature and an increase in seasonality and precipitation. The changes in temperature and seasonality follow the trend described for the EOT in southern Europe; however, the increase in precipitation is the opposite of what would be expected. This increase might be related to the stratigraphic location of the Sarral Priabonian leaf bed within a dry stage of a precession cycle, whereas the Cervera Rupelian leaf bed would be located within the wet stage of a similar cycle. CLAMP combined with sedimentology, taphonomy and palaeoecology reveals that precession cycles would produce a shift in the habitat of certain plants during the EOT, with the Lauraceae being limited to riparian communities during the Priabonian of Sarral to grow in small laurisilvas during the Rupelian of Cervera. [ABSTRACT FROM AUTHOR]

The Cretaceous–Paleogene (K/Pg) boundary has traditionally been considered a key moment in charophyte evolution, marked by the extinction of two important Mesozoic families, the Porocharaceae and the Clavatoraceae, and a major turnover within the Characeae. However, new data presented here suggest that one species of the European Porocharaceae (based on gyrogonites) and one species of the Clavatoraceae (based on thalli), persisted into the basal Danian. In addition, a taxonomic revision of the Characeae, coupled with an updated biostratigraphy, shows that this family underwent a step-wise extinction during the latest Cretaceous with only a small number of species becoming extinct at the K/Pg boundary. As a result, changes in charophyte floras around the K/Pg boundary in Europe cannot be considered to represent a major turnover in charophyte evolution. Its effects were more comparable to a normal stage boundary event rather than to a major erathem boundary one. Similar disappearance patterns at the K/Pg boundary have also been recorded in other taxa, including fish and amphibians, showing that aquatic freshwater biotas may somehow be resilient to catastrophic events such as those that occurred during the K/Pg crisis. • The effects of the K/Pg biotic crisis on European charophytes are revisited. • Characeae followed a step-wise extinction in the Latest Cretaceous. • The Porocharaceae and Clavatoraceae shortly survived after the K/Pg boundary. • Habitat specialization and biogeographic restriction contributed to extinction. • Other freshwater groups have a similar resilience as charophytes to environmental changes. [ABSTRACT FROM AUTHOR]

Abstract The Middle Jurassic section from the Kef El Anéba in southern Tunisia, near the Beni Kheddache area, provided exceptionally species-rich charophyte assemblages that are studied here for the first time. The Krachoua Formation yielded a Bajocian assemblage composed of Porochara fusca , P. schudackii nov sp., P. kimmeridgensis , P. westerbeckensis , Auerbachichara saidakovskyi , Stenochara sp., Stellatochara aff. subsphaerica , Aclistochara longiformis and Aclistochara africana. A second assemblage from the Krechem El Miit Member (Foum Tataouine Formation), of Late Callovian age, includes Auerbachichara tataouinensis nov. sp., Porochara kimmeridgensis , P. westerbeckensis , P. douzensis , P. obovata var. gondwanensis nov. var. and Mesochara voluta. Taphonomic and paleoenvironmental data suggest autochthony of these two assemblages in a brackish lagoon and a temporary freshwater pond from a littoral environment, respectively. In addition, these floras suggest that Middle Jurassic charophyte biodiversity formed an evolutionary bridge between Upper Triassic charophyte floras dominated by genera Stellatochara, Stenochara and Auerbachichara and Upper Jurassic floras dominated by Porochara, Aclistochara and Mesochara. Furthermore, the biogeography of Middle Jurassic charophytes from southern Tunisia provides further arguments to support the hypothesis of significant biological exchanges between Laurasian and Gondwanan islands, indicating that Peri-tethyan biogeography remained relatively uniform during the Middle Jurassic. Highlights • Middle Jurassic charophyte assemblages were first reported from southern Tunisia. • The flora represents the most diverse Jurassic charophyte species known so far. • The new finds shed new light on the Middle Jurassic charophyte evolution. • Middle Jurassic biogeographic flow between Laurasia and Gondwana was highlighted. [ABSTRACT FROM AUTHOR]

Rapid cooling during the Eocene-Oligocene transition resulted in a vegetation shift in southern France, from warm, humid vegetation to open savannah-like vegetation; however, the precise nature of this shift is uncertain. In this paper, we study the latest Eocene flora from the Saint-Chaptes and Alès basins (southern France) and compare it with other well-known southern European localities to evaluate vegetation changes near the Eocene-Oligocene boundary. Five plant communities are recognised: 1) hydrophytic vegetation dominated by water lilies and a Limnobiophyllum -like plant; 2) reeds that formed a palustrine belt around the lake; 3) ferns with Osmunda aff. parschlugiana and Pronephrium stiriacum , conifers with Doliostrobus taxiformis , a Sequoia -like plant, angiosperms with Daphnogene sp. , Byttneriopsis sp., Myrica sp., Comptonia difformis and palms, which inhabited the lake shores and constituted the riparian vegetation; 4) Tetraclinis , which grew just behind the riparian vegetation but not far from watercourses, forming open landscapes and 5) Zizyphus ziziphoides , Fabaceae, and probably Ailanthus sp. and Tetraclinis forming an open woodland distal to the lake. The flora of the Saint-Chaptes and Alès basins resembles coeval floras from Sarral (Catalonia, Spain) that are characteristic of Southern Europe, although riparian vegetation is more diverse in the Saint-Chaptes and Alès basins, and Fabaceae diversity is higher at Sarral. We hypothesise that vegetation composition was mainly controlled by (1) basin architecture, allowing for a variety of wetland habitats and (2) climate. The coexistence of genera that are restricted to Central Europe (e.g., Byttneriopsis or Doliostrobus), together with genera more typical of Southern Europe (e.g., diversity of Fabaceae, C. difformis and Z. ziziphoides) suggests that the Saint-Chaptes and Alès basins contain latest Priabonian floras that are transitional between these two regions. • Plant paleoecology at the EOT is studied in the Alès and Saint-Chaptes basins (France). • Plant communities range from lacustrine, wetlands to savannah-like woodlands. • The riparian vegetation is more diverse than in other coeval South European plant sites. • Alès and Saint-Chaptes flora shows taxa characteristic either South or Central Europe. • These plants represent a transitional flora between the two main European vegetations. [ABSTRACT FROM AUTHOR]

The global trend towards a colder and more arid climate at the Eocene-Oligocene boundary triggered significant changes in the European flora. Here we study the latest Eocene (Priabonian) flora from lacustrine deposits at Sarral in the Ebro Basin, Catalonia, Spain, to evaluate vegetation changes near this boundary. Three main taphofacies are recognised: (1) assemblages composed of small, size-sorted leaves represented by Zizyphus , Fabaceae leaflets and Pinus needles, inferred to be wind transported from open woodlands located distal from the lake; (2) assemblages composed of whole unsorted leaves belonging to Salicaceae, Myricaceae ( Myrica arensi and Comptonia schrankii ), Lauraceae ( Daphnogene and Laurophyllum ) and helophytic plant stems, interpreted as remains of a riparian community; (3) assemblages comprising disarticulated organs of Tetraclinis , Cupressaceae and a few torn leaves of Myrica arensi and Salicaceae, interpreted as derived from riparian or open woodland vegetation upstream from the lake. The Priabonian Sarral flora is similar to the nearby early Oligocene flora of Cervera, making it difficult to distinguish the effects of the Eocene-Oligocene climatic crisis upon the vegetation. Sedimentological analysis indicates that the Sarral leaf bed represents deposition during a drier period of small-order climate cycles, whereas the Cervera flora represents vegetation during a wetter period of a similar cycle but under the cooler and more arid environmental conditions of the early Oligocene, thereby disguising large-scale Eocene-Oligocene climatic change. Understanding such short-term sedimentary and climatic cycles is crucial in order to correctly interpret the regional climatic signal based on leaf physiognomy. [ABSTRACT FROM AUTHOR]

This work characterizes for the first time the 500–700 m-thick uppermost Cretaceous continental sedimentary succession of the Allueva Fm recorded in the northeastern margin of the Iberian basin, in the Montalbán subbasin (Maestrazgo domain, Spain). The middle-upper Campanian age of this unit constrained here by new paleomagnetic and biostratigraphic data involves major revision of previous stratigraphic and palaeogeographic interpretations. The uplift of the northern marginal areas of the Montalbán subbasin onwards from the middle Campanian supplied the coarse terrigenous-clastic sediments common in the alluvial Allueva Fm. Moreover, a sharp increase of the sedimentation rates (from 4 to 19 cm/ky) from the lower to the middle-upper part of the Allueva Fm has been related to further increase of the tectonic activity during the middle part of the late Campanian. Also relevant are the new discovered vertebrate sites mostly found in the marginal areas of a large lacustrine-palustrine carbonate system developed during the latest Campanian. Vertebrate sites include a fossil assemblage with abundance of titanosaur sauropod dinosaurs as well as the presence of ornithopod dinosaurs and crocodylomorphs. A review of the dinosaur fossil sites recorded in other Iberian subbasins shows a similar fossil assembage occurrence during the late Campanian–earliest Maastrichtian timespan, previous to the faunal turnover that took place in the Ibero-Armorican landmass around the onset of the late Maastrichtian. The stratigraphic, sedimentological and paleontological characterization of the successions recorded during the initial stages of development of the Montalbán subbasin have major implication to understand the latest Cretaceous palaeogeographic evolution of northeast Iberia. Comparative review to other latest Cretaceous continental successions deposited in other domains of the Iberian basin indicates a south to north migration of newly developed subsident subbasins: during the Campanian (South Iberian domain), during the middle-late Campanian (northern Maestrazgo domain), and during the Maastrichtian (central Castillian domain). • Review of continental subbasins formed during the latest Cretaceous in the Iberian basin. • South-north migration of the onset of formation of subsident subbasins in the Iberian basin. • A middle-late Campanian Montalbán subbasin related to the uplift of northern margin. • The Montalbán subbasin records increassing sedimentation rates during mid-late Campanian. • New vertebrate uppermost Campanian fossil sites with titanosaurs and ornithopods. • Common late Campanian-earliest Maastrichtian fossil sites with titanosaurs in the Iberia basin. [ABSTRACT FROM AUTHOR]

The early diversification of angiosperms in diverse ecological niches is poorly understood. Some have proposed an origin in a darkened forest habitat and others an open aquatic or near aquatic habitat. The research presented here centers on Montsechia vidalii, first recovered from lithographic limestone deposits in the Pyrenees of Spain more than 100 y ago. This fossil material has been poorly understood and misinterpreted in the past. Now, based upon the study of more than 1,000 carefully prepared specimens, a detailed analysis of Montsechia is presented. The morphology and anatomy of the plant, including aspects of its reproduction, suggest that Montsechia is sister to Ceratophyllum (whenever cladistic analyses are made with or without a backbone). Montsechia was an aquatic angiosperm living and reproducing below the surface of the water, similar to Ceratophyllum. Montsechia is Barremian in age, raising questions about the very early divergence of the Ceratophyllum clade compared with its position as sister to eudicots in many cladistic analyses. Lower Cretaceous aquatic angiosperms, such as Archaefructus and Montsechia, open the possibility that aquatic plants were locally common at a very early stage of angiosperm evolution and that aquatic habitats may have played a major role in the diversification of some early angiosperm lineages. [ABSTRACT FROM AUTHOR]

Three new species of ostracodes are reported from the dinosaur-bearing Escucha Formation at Ariño in Eastern Spain (Iberian Range): Rosacythere denticulata sp. nov., Theriosynoecum escuchaensis sp. nov. and Theriosynoecum arinnoensis sp. nov. Associated charophyta include Clavator harrisii harrisii and Clavator harrisii zavialensis indicating a Lower Albian age, therefore extending the stratigraphic range of the genus Theriosynoecum into the Albian in southern Europe. The environment of deposition for the dinosaur bonebed is interpreted as permanent lacustrine given the association of limnic ostracodes and charophytes. [ABSTRACT FROM AUTHOR]

Abstract: A new locality yielding angiosperm seeds and fruits is reported from the Maastrichtian of south-eastern Pyrenees. The seeds Bergacarpon viladricii gen. et sp. nov may have been produced by a monocot (probably a commelinid) based on the presence of a micropylar lid and orthotropous (atropous) development. The associated fruit is follicle-like and likely contained a single seed. The seeds form a massive accumulation in one bed in a brackish mudflat depositional setting. Size, shape and organ selection as well as the absence of other associated megafossil plant remains suggest that the seed bed originated from a paucispecific source plant community and by transport through floatation. This is one of the oldest monotypical angiosperm (probably monocot) seed accumulations found so far in the fossil record. [Copyright &y& Elsevier]

Abstract: In Tunisia, in the platform domain, the Aptian-Albian transition is associated with a major stratigraphic gap not precisely dated, which is related to the subaerial exposure of the Aptian Orbata platform. Locally, in central Tunisia (Jebel Kebar), this gap is substituted by the sedimentary records of the Kebar Formation. This formation provided a rich association of fossil charophytes, formed by Atopochara trivolvis trivolvis, Clavator harrisii zavialensis and Sphaerochara verticillata which allows attributing it to the late Aptian–early Albian interval (most probably early Albian). In addition, a new variety, Sphaerochara verticillata var. kebariensis, is described. The charophyte assemblage shows significant biogeographic affinities with a coeval flora found in the Iberian Peninsula. The Kebar Formation was previously regarded as exclusively nonmarine, but the presence of the assemblage of charophytes and associated ostracods described rather indicates a fluctuation between margino-littoral (lagoonal) and continental environments. [Copyright &y& Elsevier]