Revision of the Maastrichtian-Palaeocene charophyte biostratigraphy of the Fontllonga reference section (southern Pyrenees, Catalonia, Spain)

The Fontllonga section is one of the best-known stratigraphic sections wordwide for the study of charophyte biostratigraphy of the Maastrichtian and lower Palaeocene. An updated proposal for the charophyte biostratigraphy of this section is presented after summarizing previous knowledge. The zone of Peckichara cancellata allows the upper Campanian-lowermost Maastrichtian to be characterised in the base of the section (La Maçana Formation). The Microchara punctata biozone represents most of the Maastrichtian (Figuerola Formation). Within this biozone, a Clavator ultimus subzone is proposed to improve characterisation of the lower and middle Maastrichtian. Both the upper and lower boundaries of the Microchara punctata biozone proposed in previous studies are modified based on new occurrences of the index species. A charophyte assemblage belonging to the Dughiella bacillaris biozone is reported for the first time from the middle of the section (Perauba Complex) and provides an age for this unit ranging from the upper Danian to lower Thanetian. A foraminifer assemblage found in the basal marine deposits above the non-marine succession of the Fontllonga section provides new biostratigraphic data to locate the upper boundary of the non-marine succession at least within the upper Thanetian

Revision of the Maastrichtian-Palaeocene charophyte biostratigraphy of the Fontllonga reference section (southern Pyrenees, Catalonia, Spain)

The Fontllonga section is one of the best-known stratigraphic sections wordwide for the study of charophyte biostratigraphy of the Maastrichtian and lower Palaeocene. An updated proposal for the charophyte biostratigraphy of this section is presented after summarizing previous knowledge. The zone of Peckichara cancellata allows the upper Campanian–lowermost Maastrichtian to be characterised in the base of the section (La Maçana Formation). The Microchara punctata biozone represents most of the Maastrichtian (Figuerola Formation). Within this biozone, a Clavator ultimus subzone is proposed to improve characterisation of the lower and middle Maastrichtian. Both the upper and lower boundaries of the Microchara punctata biozone proposed in previous studies are modified based on new occurrences of the index species. A charophyte assemblage belonging to the Dughiella bacillaris biozone is reported for the first time from the middle of the section (Perauba Complex) and provides an age for this unit ranging from the upper Danian to lower Thanetian. A foraminifer assemblage found in the basal marine deposits above the non-marine succession of the Fontllonga section provides new biostratigraphic data to locate the upper boundary of the non-marine succession at least within the upper Thanetian

Peat-forming plants in the Maastrichtian coals of the Eastern Pyrenees

The Lower Maastrichtian of Fumanya and neighbouring localities of the Vallcebre syncline (Eastern Pyrenees, Catalonia) provide the first taphonomic evidence for the hypothesis that cheirolepidiacean conifers were significant precursors of Maastrichtian Pyrenean coal. Most Frenelopsis-rich lignite beds do not bear rootlet marks, suggesting that the original peat was detrital. Sedimentological and taphonomic evidence indicates deposition in the margins of a lagoon after the transport of the cheirolepidiacean remains by flotation. The same parautochtonous assemblage includes complete impressions Sabalites longirhachis leaves and large impressions of logs attributed to the same palm trees. Other parautochthonous or allochthonous plant megaremains include extremely rare cycadalean and monocot leaves and abundant minute angiosperm seeds. Rootlet marks associated with thin lignite beds occur at the top of some charophyte limestones. The charophyte association, dominated by in situ accumulation of Peckichara and Microchara gyrogonites, suggests that these limestones were deposited in shallow, freshwater lakes and that the corresponding peat mires were limnic rather than paralic in nature. The botanical affinity of plant remains associated with these root-bearing lignites is uncertain. Palynological analysis showed abundant bisaccates, with less abundant fern spores and freshwater algal oospores. Locally, the abundant rootlet marks were associated with large brush-like rooting structures attributed to Sabalites longirhachis palms. Our results show that, at the beginning of the Maasrichtian, cheirolepidiacean conifers were still significant peat-producing plants, although, unlike analogous Lower Cretaceous ones, they shared this role with rare angiosperms, such as palms

Els caròfits de les fàcies continentals i transicionals del Garumnià basal (Cretaci superior) del Pirineu Oriental

[cat] Aquesta tesi té com a objectiu fonamental la caracterització taxonòmica, biostratigràfica i paleoecològica de les associacions de caròfits de les fàcies lacustres i transicionals del Garumnià basal (Cretaci superior) de les Conques de Vallcebre, Coll de Nargó, Tremp i Àger. L’altre objectiu d’aquesta tesi és la caracterització tafonòmica i paleoecològica de les restes fòssils de plantes vasculars productores dels lignits garumnians. La flora de caròfits del Garumnià basal està constituïda per girogonits de Feistiella malladae, Peckichara cancellata, P. sertulata, Microchara cristata, M. parazensis, Platychara caudata, P. turbinata i Dughiella obtusa, i utricles de Clavator brachycerus. Pel que fa als òrgans vegetatius les calcàries garumnianes son molt riques en tal•lus de grans dimensions de Charaxis sp. associats a Peckichara sp., i de tal•lus més gràcils de Clavatoraxis microcharophorus Villalba-Breva et Martín-Closas 2011, portadors de Microchara sp. També és freqüent la presència de Munieria grambastii associada a vegades a Clavator brachycerus. Des del punt de vista biostratigràfic, les associacions de caròfits de les conques d’Àger i Vallcebre pertanyen a la biozona de caròfits Peckichara cancellata (Campanià superior - Maastrichtià inferior basal), mentre que les associacions de caròfits de les conques de Coll de Nargó i Tremp pertanyen a la biozona Septorella ultima (Maastrichtià inferior). En base a l’estudi estratigràfic i sedimentològic i l’anàlisi de microfàcies s’ha determinat que la sedimentació a la Conca d’Àger està formada majoritàriament per calcàries lacustres organitzades en centenars de seqüències de somització, que van des de fàcies lacustres profundes, passant per ambients marginals, ben il•luminats dominats per herbeis de caràcies, fins a fàcies de vora de llac dominades per herbeis de clavatoràcies. A les conques de Vallcebre, Coll de Nargó i Tremp, la sedimentació del Garumnià basal està organitzada en diversos cicles, els quals comencen amb dipòsits salabrosos formats per margues amb mol•luscs eurihalins a la base, seguits per lignits i calcàries d’ambients salabrosos dominades per porocaràcies, i calcàries d’aigua dolça amb caràcies i clavatoràcies. Les diferències en el registre sedimentari i la flora de caròfits mostren que les conques sud pirinenques presentaven una polaritat de fàcies sud-nord durant l’inici de la sedimentació continental del Cretaci superior, i que aquesta continentalització va començar al sud i desprès va continuar al nord, d’est a oest. L’estudi de la macroflora del Garumnià basal de les conques de Vallcebre, Coll de Nargó i Tremp indica que la comunitat vegetal dels aiguamolls del Maastrichtià inferior estava dominada per la conífera queirolepidiàcia Frenelopsis, que va ser la planta productora de la matèria orgànica precursora del lignit. Associada a aquestes coníferes hi havia la palmera Sabalites longirhachis, i en alguns casos altres angiospermes d’aiguamoll, representades per les seves llavors, especialment Bergacarpon viladricii Marmi, Gomez, Villalba-Breva et Martín-Closas 2012. Altres plantes vasculars significatives encara que menys abundants eren les falgueres, cicadals i pandanals.[eng] This thesis aims to characterize the taxonomy, biostratigraphy and palaeoecology of charophyte assemblages of lacustrine and transitional facies from the basal Garumnian (Late Cretaceous) of the Vallcebre, Coll de Nargó, Tremp and Àger basins. The other objective of this study is the taphonomic and palaeoecological characterization of the precursory vascular plants of the Garumnian lignite. The charophyte flora of the basal Garumnian consists of gyrogonites of Feistiella malladae, Peckichara cancellata, P. sertulata, Microchara cristata, M. parazensis, Platychara caudata, P. turbinata and Dughiella obtusa, and utricles of Clavator brachycerus. Regarding the vegetative organs, Garumnian limestones are rich in large thalli of Charaxis sp. associated to Peckichara sp., and smaller thalli of Clavatoraxis microcharophorus Villalba-Breva et Martín-Closas 2011, with attached Microchara sp. Also Munieria grambastii thalli are abundant, associated sometimes with Clavator brachycerus. From a biostratigraphic point of view, charophyte assemblages of Vallcebre and Àger basins belong to the Peckichara cancellata biozone (Late Campanian – Earliest Maastrichtian), while charophyte assemblages of Coll de Nargó and Tremp basins belong to the Septorella ultima biozone (Early Maastrichtian). Based on the sedimentological and stratigraphic studies and microfacies analyses, the sedimentation in the Àger Basin is organised into hundreds of small order sedimentary cycles corresponding to lacustrine infilling sequences, ranging from deep lacustrine facies, through marginal environments dominated by characean meadows, to lakeshore facies dominated by clavatorecean meadows. In the Vallcebre, Coll de Nargó and Tremp basins, the deposits of the basal Garumnian are organized into small number of cycles that show a transition from brackish deposits formed by marls with euryhaline molluscs, lignites and limestones with porocharaceans, to lacustrine limestones with characeans and clavatoraceans. The differences in the sedimentary record and in the charophyte flora show that the Southern Pyrenean Basin displayed a south to north shift of facies during the onset of the Upper Cretaceous continental sedimentation and that this continentalisation began in the south and then continued to north, from east to west. The study of megafossil plant remains from the basal Garumnian of the Vallcebre, Coll de Nargó and Tremp basins indicates that the cheirolepidiacean conifer Frenelopsis was the main component of the wetlands vegetation associated with Sabalites longirhachis palms, and in some cases with other angiosperms, such as the plant bearing Bergacarpon viladricii Marmi, Gomez, Villalba-Breva et Martín-Closas 2012, probably a commelinid

Peat-forming plants in the Maastrichtian coals of the Eastern Pyrenees

The Lower Maastrichtian of Fumanya and neighbouring localities of the Vallcebre syncline (Eastern Pyrenees, Catalonia) provide the first taphonomic evidence for the hypothesis that cheirolepidiacean conifers were significant precursors of Maastrichtian Pyrenean coal. Most Frenelopsis-rich lignite beds do not bear rootlet marks, suggesting that the original peat was detrital. Sedimentological and taphonomic evidence indicates deposition in the margins of a lagoon after the transport of the cheirolepidiacean remains by flotation. The same parautochtonous assemblage includes complete impressions Sabalites longirhachis leaves and large impressions of logs attributed to the same palm trees. Other parautochthonous or allochthonous plant megaremains include extremely rare cycadalean and monocot leaves and abundant minute angiosperm seeds. Rootlet marks associated with thin lignite beds occur at the top of some charophyte limestones. The charophyte association, dominated by in situ accumulation of Peckichara and Microchara gyrogonites, suggests that these limestones were deposited in shallow, freshwater lakes and that the corresponding peat mires were limnic rather than paralic in nature. The botanical affinity of plant remains associated with these root-bearing lignites is uncertain. Palynological analysis showed abundant bisaccates, with less abundant fern spores and freshwater algal oospores. Locally, the abundant rootlet marks were associated with large brush-like rooting structures attributed to Sabalites longirhachis palms. Our results show that, at the beginning of the Maasrichtian, cheirolepidiacean conifers were still significant peat-producing plants, although, unlike analogous Lower Cretaceous ones, they shared this role with rare angiosperms, such as palms

Revision of the Maastrichtian-Palaeocene charophyte biostratigraphy of the Fontllonga reference section (southern Pyrenees, Catalonia, Spain)

The Fontllonga section is one of the best-known stratigraphic sections wordwide for the study of charophyte biostratigraphy of the Maastrichtian and lower Palaeocene. An updated proposal for the charophyte biostratigraphy of this section is presented after summarizing previous knowledge. The zone of Peckichara cancellata allows the upper Campanian-lowermost Maastrichtian to be characterised in the base of the section (La Maçana Formation). The Microchara punctata biozone represents most of the Maastrichtian (Figuerola Formation). Within this biozone, a Clavator ultimus subzone is proposed to improve characterisation of the lower and middle Maastrichtian. Both the upper and lower boundaries of the Microchara punctata biozone proposed in previous studies are modified based on new occurrences of the index species. A charophyte assemblage belonging to the Dughiella bacillaris biozone is reported for the first time from the middle of the section (Perauba Complex) and provides an age for this unit ranging from the upper Danian to lower Thanetian. A foraminifer assemblage found in the basal marine deposits above the non-marine succession of the Fontllonga section provides new biostratigraphic data to locate the upper boundary of the non-marine succession at least within the upper Thanetian

Peat-forming plants in the Maastrichtian coals of the Eastern Pyrenees

The Lower Maastrichtian of Fumanya and neighbouring localities of the Vallcebre syncline (Eastern Pyrenees, Catalonia) provide the first taphonomic evidence for the hypothesis that cheirolepidiacean conifers were significant precursors of Maastrichtian Pyrenean coal. Most Frenelopsis-rich lignite beds do not bear rootlet marks, suggesting that the original peat was detrital. Sedimentological and taphonomic evidence indicates deposition in the margins of a lagoon after the transport of the cheirolepidiacean remains by flotation. The same parautochtonous assemblage includes complete impressions Sabalites longirhachis leaves and large impressions of logs attributed to the same palm trees. Other parautochthonous or allochthonous plant megaremains include extremely rare cycadalean and monocot leaves and abundant minute angiosperm seeds. Rootlet marks associated with thin lignite beds occur at the top of some charophyte limestones. The charophyte association, dominated by in situ accumulation of Peckichara and Microchara gyrogonites, suggests that these limestones were deposited in shallow, freshwater lakes and that the corresponding peat mires were limnic rather than paralic in nature. The botanical affinity of plant remains associated with these root-bearing lignites is uncertain. Palynological analysis showed abundant bisaccates, with less abundant fern spores and freshwater algal oospores. Locally, the abundant rootlet marks were associated with large brush-like rooting structures attributed to Sabalites longirhachis palms. Our results show that, at the beginning of the Maasrichtian, cheirolepidiacean conifers were still significant peat-producing plants, although, unlike analogous Lower Cretaceous ones, they shared this role with rare angiosperms, such as palms

Reconstructing the foraging environment of the latest titanosaurs (Fumanya dinosaur tracksite, Catalonia)

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. (C) 2014 Elsevier B.V. All rights reserved

A reconstruction of the fossil palm Sabalites longirhachis (Unger) J. Kvacek et Herman from the Maastrichtian of Pyrenees

International audienceFragmented leaf laminas were the only organ known of the fossil palms Sabalites longirhachis (Unger) J. Kvacek 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 14 m 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 1.5 m 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. (C) 2010 Elsevier B.V. All rights reserved. Accession Number: W

Bergacarpon viladricii gen. et sp nov., angiosperm seeds and associated fruits from the early Maastrichtian of the eastern Pyrenees (Catalonia, Spain)

International audienceA 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