Subjects -> PALEONTOLOGY (Total: 46 journals)
Showing 1 - 21 of 21 Journals sorted alphabetically
Acta Palaeontologica Polonica     Open Access   (Followers: 6)
Alcheringa: An Australasian Journal of Palaeontology     Hybrid Journal   (Followers: 7)
Ameghiniana     Open Access   (Followers: 1)
Annales de Paléontologie     Full-text available via subscription   (Followers: 7)
Annals of Carnegie Museum     Full-text available via subscription   (Followers: 1)
Boreas: An International Journal of Quaternary Research     Hybrid Journal   (Followers: 12)
Comptes Rendus Palevol     Full-text available via subscription  
European Journal of Protistology     Hybrid Journal   (Followers: 6)
EvoDevo     Open Access   (Followers: 4)
Facies     Hybrid Journal   (Followers: 10)
Fossil Record     Open Access   (Followers: 5)
Geobios     Full-text available via subscription   (Followers: 6)
Historical Biology: An International Journal of Paleobiology     Hybrid Journal   (Followers: 9)
Ichnos: An International Journal for Plant and Animal Traces     Hybrid Journal  
International Journal of Speleology     Open Access   (Followers: 3)
Journal of Paleolimnology     Hybrid Journal   (Followers: 6)
Journal of Paleontology     Hybrid Journal   (Followers: 11)
Journal of Quaternary Science     Hybrid Journal   (Followers: 32)
Journal of Vertebrate Paleontology     Full-text available via subscription   (Followers: 12)
Marine Micropaleontology     Hybrid Journal   (Followers: 2)
Micropaleontology     Full-text available via subscription  
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen     Full-text available via subscription   (Followers: 4)
Novitates Paleoentomologicae     Open Access   (Followers: 1)
Open Quaternary     Open Access   (Followers: 1)
Palaeogeography, Palaeoclimatology, Palaeoecology     Hybrid Journal   (Followers: 13)
Palaeontology     Hybrid Journal   (Followers: 18)
Palaeoworld     Hybrid Journal   (Followers: 3)
PALAIOS     Hybrid Journal   (Followers: 7)
Paläontologische Zeitschrift     Hybrid Journal   (Followers: 4)
Paleobiology     Full-text available via subscription   (Followers: 6)
PaleoBios     Open Access   (Followers: 1)
Paleoceanography and Paleoclimatology     Full-text available via subscription   (Followers: 4)
Paleontological Journal     Full-text available via subscription   (Followers: 5)
Paleontological Research     Full-text available via subscription   (Followers: 3)
Palynology     Hybrid Journal   (Followers: 2)
Papers in Palaeontology     Hybrid Journal   (Followers: 1)
Quaternaire     Open Access   (Followers: 3)
Quaternary Research     Full-text available via subscription   (Followers: 20)
Quaternary Science Reviews     Hybrid Journal   (Followers: 25)
Review of Palaeobotany and Palynology     Hybrid Journal   (Followers: 2)
Revue de Micropaleontologie     Full-text available via subscription  
Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy)     Open Access   (Followers: 2)
Spanish Journal of Palaeontology     Open Access  
Swiss Journal of Palaeontology     Hybrid Journal   (Followers: 4)
Vertebrate Anatomy Morphology Palaeontology     Open Access   (Followers: 2)
Zitteliana     Open Access   (Followers: 4)
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Review of Palaeobotany and Palynology
Journal Prestige (SJR): 0.756
Citation Impact (citeScore): 2
Number of Followers: 2  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0034-6667 - ISSN (Online) 0034-6667
Published by Elsevier Homepage  [3305 journals]
  • Crossing taxonomic and isotopic approaches in charcoal analyses to reveal
           past climates. New perspectives in Paleobotany from the Paleolithic
           Neanderthal dwelling-site of La Combette (Vaucluse, France)
    • Abstract: Publication date: Available online 6 April 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Benjamin Audiard, Isabelle Thery-Parisot, Thierry Blasco, Carlo Mologni, Pierre-Jean Texier, Giovanna Battipaglia Robust methodology in charcoal analyses has strong potential in the reconstruction of past environments. However, charcoal assemblages from Pleistocene contexts, particularly those that formed under varying climatic conditions during glaciation and mostly composed of the genus Pinus, can neither express changes in forest density, nor can they reveal climatic conditions. Here, we explore the potential of a combined approach using taxonomic and δ13C isotopic study of archeological charcoal from middle Paleolithic sequence of La Combette. In order to investigate past climate and/or environmental conditions, we focus on charcoal of Pinus spp. from infra stratigraphic units at the site that showed a high potential for isotope analysis. Those isotopic results are consistent with other paleoenvironnemental data (anthracology, micromorphology, palynology, etc.) that are manifested at different time scales. In some cases, isotopic data provide, more accurate information than that derived from taxonomic identifications. This is due to the quicker physiological response of the plants compared to the long-term changes in forest biodiversity under climatic pressure. Subsequently, this first application of cross taxonomic and isotopic approach offers promising and original results and must be applied to different context (low to high taphonomic process). Lastly, the degree of asynchrony or synchrony between taxonomic and isotopic findings allows us to rethink Neanderthal fuel management and mobility patterns and to explain the correlation between Neanderthal occupations of the rock shelter in view of climatic conditions.
       
  • An endemic microphytoplankton assemblage from Middle Devonian Iberia and
           its paleogeographical significance
    • Abstract: Publication date: Available online 5 April 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Alexander J. Askew Diverse microphytoplankton assemblages, including 72 taxa belonging to 27 genera of acritarchs and prasinophyte phycomata, have been recovered from Middle Devonian rocks in northern Spain, revealing an endemic flora dissimilar to coeval assemblages. These deposits are of early Givetian age and consist of the laterally equivalent Naranco, Huergas and Gustalapiedra formations of Asturias, León and Palencia provinces. At the time, Iberia was part of the Armorican Terrane Assemblage, a comparatively isolated island chain positioned between Laurussia and Gondwana. The studied formations represent a marine transect across a nearshore–offshore gradient and consist of a large clastic unit sandwiched between extensive carbonate deposits. This clastic unit incorporates the Kačák Event, an important global extinction event associated with marine anoxia. Herein, the suite of generally well-preserved microphytoplankton assemblages is described and their stratigraphical and biogeographical importance are considered. The microphytoplankton represents a single assemblage deposited in a short interval and is interpreted as being endemic. The assemblage is only moderately similar to contemporary assemblages from Laurussia and Gondwana and, although certain characteristic Middle Devonian taxa are present, other common species such as Arkonites bilixus and Tyligmasoma alargada are absent. While no unique taxa are found here, the taxa which are present represent a particular combination of species not seen elsewhere. Certain taxa appear which may have discordant temporal ranges, though no major inferences can be made from them as only two taxa both occur in significant numbers and have a confident identification. This assemblage adds to our knowledge of phytoplankton paleobiogeography, representing a significantly endemic assemblage within the generally cosmopolitan microphytoplankton flora of the Middle Devonian.
       
  • Controls on amorphous organic matter type and sulphurization in a
           Mississippian Black Shale
    • Abstract: Publication date: Available online 5 April 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Joseph F. Emmings, Jan A.I. Hennissen, Michael H. Stephenson, Simon W. Poulton, Christopher H. Vane, Sarah Davies, Melanie J. Leng, Angela Lamb, Vicky Moss-Hayes Paleoredox proxies (Fe speciation, trace element and δ34Spy) integrated with sedimentological and palynological observations link the distribution and type of particulate organic matter (OM) preserved to hydrocarbon source rock potential. In the Mississippian Bowland Shale Formation (Lancashire, UK), particulate OM is dominated by “heterogeneous” amorphous OM (AOM), primarily “sharp-edged, pellet-like” (AOMpel) and “heterogeneous, granular” (AOMgr) types. AOMpel is abundant in muds deposited under anoxic and moderately to highly sulphidic conditions and most likely represents the fecal minipellets of zooplankton and/or pellets of macro-zooplankters. We recognize two intervals, “A” and “B,” which exhibit Sorg/TOC > 0.04, suggesting a bulk Type II-S kerogen composition. The Interval A palynofacies is typified by pyritized AOMpel (AOMpyr) particles that contain high-relief organic spheres surrounding individual pyrite framboids, within each AOMpyr particle. These textures are interpreted as sulphurized OM local to pyrite framboids (Sorg-PF). Sorg-PF is rarely observed in Interval B, and absent in all other samples. Redox oscillation between ferruginous and euxinic conditions during early diagenesis of Interval A likely promoted S cycling in microenvironments surrounding pyrite framboids, which generated reactive S species and reactive OM required for sulphurization. Early diagenetic redox oscillation processes were apparently triggered by relative sea level fall, associated with an increased supply of FeHR from adjacent shelves into the basin. Interval B represents deposition during the late stages of basin infill and transition from anoxic to (sub)oxic bottom waters, where AOMpel is replaced by AOMgr as the dominant type of AOM. A large particle diameter at the limit of the mesh size (500 μm), sheet-like, fragmented character, and presence of candidate organic sheaths suggests AOMgr at least partially represent fragments of benthic microbial mats, probably as sulphide-oxidizers. A ternary plot of AOMpel + AOMpyr versus AOMgr versus spores + phytoclasts links the observed palynofacies to bottom and pore water redox conditions, water column productivity and proximity to fluvial (deltaic) supply of spores and phytoclasts. These variables were moderated by changing basin accommodation, driven primarily by eustatic sea level fluctuation. A sequence-stratigraphic control on AOM type and sulphurization is important for understanding the link between source rock heterogeneity and the timing of hydrocarbon generation and expulsion from this source rock.
       
  • Lithraea australis (Berry) comb. nov. (Anacardiaceae) from the upper
           section of Ñirihuau Formation (middle Miocene), Patagonia
    • Abstract: Publication date: Available online 4 April 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Mauro G. Passalia, Nicolás Caviglia, Ezequiel I. Vera The first records of fossil plants from the Ñirihuau Formation (middle Miocene) were published by Edward Berry at the beginning of the last century. They consist of a small collection of leaf imprints obtained from the southern margin of the Ñirihuau River valley, western Río Negro, Argentina. Based on these records, Berry described a few ferns, gymnosperms and angiosperms. Among these impressions, stand out two specimens that Berry interpreted as pinnate leaves of Cycadaceae (now Zamiaceae) that he assigned to the new species Zamia australis Berry. However, after a review of Berry's original materials of Z. australis, and new specimens collected in recent years in the same fossil locality, it is concluded that these putative zamiaceous remains are in fact angiosperm leaves. They show great similarity with those of the current South American species Lithraea molleoides (Vell.) Engl. (Anacardiaceae). To encompass these remains, a new combination, Lithraea australis (Berry) is proposed. From a paleophytogeographic point of view, the recognition of a L. molleoides closely related species suggests that the plant communities of the upper section of the Ñirihuau Formation were part of the “Transitional Province” or at least constituted the ecotone between it and the “Nothofagidites” Province.
       
  • First record of orchid subfossil seeds – The abundant occurrence of
           Epipactis palustris (L.) Crantz and Dactylorhiza spp. seeds in early
           Holocene sediments from Central Europe
    • Abstract: Publication date: June 2019Source: Review of Palaeobotany and Palynology, Volume 265Author(s): Ewa Gołaszewska, Joanna Gadziszewska, Małgorzata Latałowa Numerous subfossil seeds of Epipactis palustris (L.) Crantz, and Dactylorhiza spp. (D. incarnata/maculata complex) found in early Holocene sediments in northern Poland are the first record of orchid seeds in geological formations of any age and location. The macro- and micromorphological characters of the seeds were examined to determine their taxonomic affinity. The seeds were found among numerous macroremains of aquatic and terrestrial organisms, which are distinct in effective buoyancy, enabling air and water dispersal. The orchid populations developed in a floodplain meadow where summer inundation was probably among the main agents facilitating seed dispersal and deposition in lake sediments. We discuss potential environmental factors enabling the formation and preservation of the subfossil assemblages and suggest some technical issues among the reasons for the general poverty of orchid fossil data. Our data provide the first direct evidence for the early post-glacial establishment of populations of E. palustris and species of the D. incarnata/maculata complex in the northern part of Central Europe.
       
  • Paleovegetation and paleoclimate dynamics during the last 7000 years in
           the Atlantic forest of Southeastern Brazil based on palynology of a
           waterlogged sandy soil
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Antonio Alvaro Buso Junior, Luiz Carlos Ruiz Pessenda, Francis Edward Mayle, Flávio Lima Lorente, Cecília Volkmer-Ribeiro, Jolimar Antonio Schiavo, Marcos Gervasio Pereira, José Albertino Bendassolli, Kita Chaves Damasio Macario, Geovane Souza Siqueira Mineral soils are usually considered inappropriate for pollen analysis because of the poor quality of pollen and spore preservation and the disturbed stratigraphy. However, here we present a 57 cm core, collected from a waterlogged sandy soil in the lowland Atlantic Forest of SE Brazil, which shows good stratigraphy and good preservation of pollen and spores since ~ 7000 cal. BP, both in organic and in mineral horizons. By the other hand, the decomposition of the organic matter and its translocation along the soil profile led to changes of C and N results (TOC, TN, C/N, δ13C and δ15N). Mid-Holocene paleoclimate inferences from this study are in accordance with climate fluctuations presented in previous studies for Central, Southeastern and Southern Brazil, when a change to more humid climate occurred at ~ 7000 cal BP. The process responsible for the presence of biological proxies along this sandy soil profile involves the continuous deposition of these proxies together with litter and sand, and the subsequent decomposition of the litter. Ultimately, this process led to the vertical accretion of the sand with the more resistant organic structures preserved in stratigraphic sequence. The preservation of pollen and spores along the profile is probably caused by low pH and redoximorphic conditions due to water saturation. This study suggests the potential for retrieving useful paleoecological information from mineral and organic horizons of tropical waterlogged sandy soils, which is especially useful for those regions where traditional pollen archives (lakes and peat bogs) are absent.
       
  • Going north and south: The biogeographic history of two Malvaceae in the
           wake of Neogene Andean uplift and connectivity between the Americas
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Carina Hoorn, Raymond van der Ham, Felipe de la Parra, Sonia Salamanca, Hans ter Steege, Hannah Banks, Wim Star, Bertie Joan van Heuven, Rob Langelaan, Fernanda A. Carvalho, Guillermo Rodriguez-Forero, Laura P. Lagomarsino The evolution of the tropical lowland forests in northern South America is poorly understood, yet new insights into past composition and changes through time can be obtained from the rich and diverse fossil pollen record. Here we present a revision of two diagnostic Malvaceae taxa from the Cenozoic record of northern South America and we relate their evolutionary history to recently updated geological models. In our study we review the pollen morphology and botanical affinity of Rhoipites guianensis and Malvacipolloides maristellae, and integrate these data into a phylogenetic framework. We also produce distribution maps for both fossil and extant taxa, infer the phylogeny and historical biogeography of the lineages to which they belong, and identify their ecological associates and environmental settings. The closest extant relatives of Rhoipites guianensis (Grewioideae) are Vasivaea and Trichospermum, which are taxa of South American origin. During the late Eocene to early Miocene Rhoipites guianensis was widely distributed in the lowland floodplain environments of northern South America. The closest living relatives of Malvacipolloides maristellae (Malvoideae) are members of Abutilinae (e.g., Abutilon, Bakeridesia, Callianthe and Herissantia), which have their origin in the northern hemisphere. This taxon makes its first appearance in the fossil record of northern South America during the early Miocene, and is typically found in fresh water floodplain and lacustrine environments. Our study suggests that both taxa migrated across the Central American Seaway in the early Miocene (around 18 Ma), and virtually disappeared from the fossil record in northern South America during the middle Miocene, coinciding with Andean uplift. However, their descendants expanded and -in the case of the Abutilinae—diversified in the Andes. We conclude that the biogeographic history of these Malvaceae is influenced by Andean uplift and the incipient bridging of the Americas. Thereafter, climate change and diversification of the Andean landscape enabled their descendants to move upslope and into the Andes.
       
  • Speleothem evidence for C3 dominated vegetation during the Late Miocene
           (Messinian) of South Africa
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Philip J. Hopley, Hazel Reade, Randall Parrish, Michiel De Kock, Justin W. Adams During the Late Miocene, Africa experienced a number of ecological transitions including the spread of C4 grasslands, the expansion of the Sahara Desert, the Messinian Salinity Crisis and a number of mammalian migrations and expansions, including the origin of the hominin clade. A detailed understanding of the relationship between environmental change and hominin evolution is hampered by the paucity of data available from terrestrial localities, especially in southern Africa. Here, we present a stable isotope and trace element record from a speleothem from the South African cave site of Hoogland. Uranium-lead dating and magnetostratigraphy places the speleothem within the Messinian Age (7.25–5.33 Ma) of the Late Miocene, making it the oldest known cave deposit from the region near the UNESCO Fossil Hominids of South Africa World Heritage Site (locally known as the “Cradle of Humankind”). Low carbon isotope values indicate a predominantly C3 vegetation in the vicinity of the cave throughout the period of speleothem growth. It is not possible to determine if this represents a C3 grassland or a C3 woodland, but it is clear that an equivalent C3-rich environment has yet to be found during the Messinian of east Africa. We conclude that the C4 grass expansion occurred millions of years later in South Africa than it did in eastern Africa, and that this vegetation shift should be considered when comparing African vegetation change with the late Miocene hominin fossil record.
       
  • Relative pollen productivity estimates in the forest steppe landscape of
           southeastern Romania
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Roxana Grindean, Anne Birgitte Nielsen, Ioan Tanţău, Angelica Feurdean Estimates of relative pollen productivity (RPP) represent key input parameters for model-based quantitative reconstructions of past vegetation cover. In this study, we provide the first RPP estimates for 13 taxa from the forest steppe ecoregion in southeastern Romania (southeastern Europe). We used modern pollen assemblages from 26 points together with vegetation surveys and mapping, covering a 1.5 km radius around each sampling site. We have estimated the relevant source area of pollen (RSAP) and pollen productivity for 13 taxa relative to Poaceae using the ERV (Extended R-value model), sub-model 3, as this model shows the best goodness of fit. The estimated RSAP is about 100 m and falls within the range of RSAP estimates of moss pollsters and forest hollows from other RPP-related studies. Results show that Rubiaceae (7.97), Apiaceae (5.91), Artemisia (5.89) and Fraxinus (2.99) are high pollen producers compared to Poaceae, while Plantago lanceolata (0.58), Fabaceae (0.40), Acer (0.30), Rosaceae (0.29), Carpinus orientalis (0.24), Cerealia (0.22) and Asteraceae (0.16) are low pollen producers with lower RPPs than Poaceae. Quercus (1.10) has a pollen productivity close to that of Poaceae. The RPPs for Carpinus orientalis and Fabaceae are published here the first time for Europe. The high pollen producing plants include both entomophilous and anemophilous species, while the low pollen producers are mostly entomophilous species. Our results form an essential contribution to improving the accuracy of quantitative reconstruction of forest steppe ecoregion in Europe and generally in regions with a similar climate and vegetation setting.
       
  • Lutetian to Priabonian dinocyst assemblages from the northwestern Tethyan
           margin (Adelholzen section, Eastern Alps, Germany)
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Omar Mohamed, Hans Egger This paper is the first systematic documentation of Eocene organic-walled dinoflagellate cyst (dinocyst) assemblages from the northwestern shelf of the Tethys. A taxonomic list of the rich and well-preserved dinocyst assemblages found within 28 samples collected at the Adelholzen section in southeastern Germany is presented herein. The sediments accumulated during the Lutetian and Priabonian stages at a ramp-type margin. One-hundred organic-walled dinocyst species were found at the section, which is riddled with unconformities. The composition of the successive dinocyst assemblages reflects the sea-level changes within the depositional area. Areoligera coronata and Cordosphaeridium gracile dominate the assemblage within the glauconite-rich siliciclastic sandstone (lower Adelholzen beds) of the lower transgressive system tract, which spans the calcareous nannoplankton sub-Zones NP15a and NP15b. A hiatus comprising at least c. 1.5 million years truncates these deposits and indicates an erosional episode. Rapid sea-level rise in Biochron NP16 caused a new transgression and the deposition of calcareous marlstone and limestone rich in nummulitids. In this part of the section (middle Adelholzen beds), Homotryblium tenuispinosum is by far the most abundant dinocyst species, and rare but consistent occurrences of Impagidinium spp. suggest a more open marine environment. A lithological shift from limestone to marlstone, a change from nummulitids to discocyclinids, and finally the complete disappearance of larger benthic foraminifera indicates continuous deepening of the environment. An increase in Spiniferites spp., Operculodinium spp., and occurrences of Homotryblium floripes characterize the dinocyst assemblage of this marlstone (upper Adelholzen beds). A 0.5 m thick condensed layer, which consists essentially of iron-coated glauconite grains and scattered phosphate nodules, represents the maximum flooding surface of the transgressive sequence, for which a paleodepth of c. 300 m is assumed. The overlying marlstone (“Stockletten”) of the highstand system tract is punctuated by a hiatus of c. 4.3 million years spanning the entire Bartonian. The stratigraphically important species Rhombodinium longimanum, Rhombodinium perforatum, Distatodinium ellipticum, Nematosphaeropsis labyrinthus and Selenopemphix nephroides have their lowest occurrences in the Priabonian (Zones NP18 and NP19) of the section.
       
  • Impagidinium detroitense and I.' diaphanum: Two new dinoflagellate
           cyst species from the Pliocene of the North Pacific Ocean, and their
           biostratigraphic significance
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Coralie Zorzi, Martin J. Head, Jens Matthiessen, Anne de Vernal Palynological investigations of Pliocene–Pleistocene sediments from Ocean Drilling Program (ODP) Holes 882A and 887C, located in the western and eastern North Pacific respectively, have revealed the occurrence of two new dinoflagellate cyst species of the genus Impagidinium Stover and Evitt, 1978. Impagidinium detroitense sp. nov. has a spheroidal to broadly ovoidal central body and finely granulate surface with suturocavate septa that are higher antapically than apically. This species is recorded from the Lower to Upper Pliocene (5.27–2.70 Ma), with a maximum abundance at 3.95–3.58 Ma and a disappearance possibly coinciding with the onset of the modern halocline in the North Pacific at 2.7 Ma. Impagidinium' diaphanum sp. nov. is a large and thin-walled species with nearly complete tabulation expressed by low and pronounced cavate septa, and an unusual ventral tabulation in which the anterior sulcal plate (as) contacts the fifth precingular plate (5′′). Impagidinium' diaphanum sp. nov. occurs within short, non-synchronous time windows during the Early Pliocene. These two new species have not been reported previously, suggesting regional endemism during the Pliocene. The stratigraphically well-defined occurrence of these two species highlights the potential of organic-walled dinoflagellate cysts for biostratigraphic applications at local to regional scales in the subarctic North Pacific.
       
  • Pollen morphology in the genus Bonamia Thouars (Convolvulaceae) and its
           taxonomic significance
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): André Luiz da Costa Moreira, Ana Carolina Mezzonato-Pires, Francisco de Assis Ribeiro Santos, Taciana Barbosa Cavalcanti Bonamia Thouars (Convolvulaceae) comprises about 60 species, widely distributed through North and South America, Africa, Madagascar, South and Southeast Asia, and Australia. Bonamia is variable, possessing at least two different pollen types, and its current circumscription is controversial. From recent phylogenetic studies in the family, it is established that Bonamia is paraphyletic. Ongoing taxonomic, morphological and molecular phylogenetic studies for the clarification of the real circumscription of Bonamia and its infrageneric relationships, have involved also the pollen analyses of 36 species of Bonamia. The pollen grains were acetolyzed and microphotographed under light microscopy and analyses under Scanning Electron Microscopy. The results increase with descriptions of pollen for taxa never described, as well as species recently described for science and have demonstrated that the pollen grains of all species analyzed are monads, with isopolar, 3-colpate (32 spp.) and 12–32-pantocolpate (4 spp.) since only two pollen types and some variations were cited for the genus we present here five pollen types divided by sections. The exine presented variable ornamentation, with microspines, granules or verrucae and formation of perforations, microreticula and reticula. The palynological features allowed the classification into two major groups: (1) with polar pollen grains and 3-colpate apertures and; (2) with apolar pollen grains with 12–32-pantocolpate. We conclude that Bonamia, in its current circumscription, is euripalynous mainly in what concerns polarity and aperture type.
       
  • The disappearance of Metasequoia (Cupressaceae) after the middle Miocene
           in Yunnan, Southwest China: Evidences for evolutionary stasis and
           intensification of the Asian monsoon
    • Abstract: Publication date: May 2019Source: Review of Palaeobotany and Palynology, Volume 264Author(s): Li Wang, Lutz Kunzmann, Tao Su, Yao-Wu Xing, Shi-Tao Zhang, Yu-Qing Wang, Zhe-Kun Zhou Metasequoia glyptostroboides Hu et W.C.Cheng (Cupressaceae) is a relic plant with a narrow natural distribution in central China. Historically, the genus Metasequoia Hu et W.C.Cheng has rich fossil records from the Cretaceous to the Pleistocene in the Northern Hemisphere, but fossil records of Metasequoia in China are still rare, which limits our knowledge of its biogeographic history under paleoenvironmental changes. Here, we describe leaves including cuticles and ovuliferous cones from the middle Miocene of Zhenyuan, Yunnan, Southwest China, comprising the southernmost fossil record of the genus worldwide. Judging by the great morphological similarity between these fossils and extant M. glyptostroboides, we identify them as Metasequoia sp. (cf. Metasequoia glyptostroboides). The material documents obviously a long lasting morphological stasis within the genus. Metasequoia sp. (cf. M. glyptostroboides) considerably expands the spatial distribution range of Metasequoia in the geological past. Furthermore, possible reasons for its disappearance in Southwest China are discussed. Together with other evidence, it is concluded that the disappearance of Metasequoia from Southwest China might be related to the evolutionary stasis of Metasequoia, most likely preventing necessary adaptations of the plants to increasing winter and spring aridity induced by the intensification of the Asian monsoon in this region during the Neogene.
       
  • A quantitative study of modern pollen–vegetation relationships in
           southern Brazil's Araucaria forest
    • Abstract: Publication date: Available online 19 March 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Macarena L. Cárdenas, Oliver J. Wilson, Lauri A. Schorn, Francis E. Mayle, José Iriarte Southern Brazil's highland Araucaria forest is ancient, diverse and unique, but its future is under significant threat from 20th Century habitat loss and 21st Century climate change. Paleoecological studies have revealed that it expanded rapidly over highland grasslands around 1000 years ago, but whether this expansion was caused by human land use or climate change has been a topic of considerable debate. Discriminating between these potential drivers has so far not been possible with fossil pollen, however, as the palynological representation of floristic and structural differences in Araucaria forest remains poorly understood. Here, we address this shortcoming using modern pollen rain from moss polsters and vegetation surveys in forest areas with minimal current human disturbance. We show that forest plots with evident structural differences lack consistent differences in their floristic composition and cannot be reliably distinguished by their pollen spectra. We quantify pollen–vegetation relationships for 27 key tree genera of Araucaria forest, showing that, despite significant intra-taxon variability, 22 of these are under-represented or absent in the pollen record. These palynologically under-represented and silent taxa include many of the forest's most ecologically important tree species, with only Araucaria, Lamanonia, Podocarpus, Myrsine and Clethra being more abundant in the pollen rain than vegetation. Our results suggest that subtle structural changes in Araucaria forest, as well as moderate to significant floristic changes, may not be clearly distinguished in fossil pollen records – an important limitation when attempting to identify past human and climatic impacts on Araucaria forest via pollen analysis.
       
  • Scanning electron microscopy investigations of middle to late Eocene
           pollen from the Changchang Basin (Hainan Island, South China) – Insights
           into the paleobiogeography and fossil history of Juglans, Fagus,
           Lagerstroemia, Mortoniodendron, Cornus, Nyssa, Symplocos and some
           Icacinaceae in SE Asia
    • Abstract: Publication date: Available online 18 March 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Christa-Ch. Hofmann, Tatiana M. Kodrul, Xiaoyan Liu, Jianhua Jin Bartonian-aged samples from the Changchang Formation (Hainan) have been palynologically analyzed using light microscopy (LM) and scanning electron microscopy (SEM). The presence of cf. Laurelia-type pollen demonstrates a wide geographical range for this family during the Eocene. A particular paleobiogeographic pattern, suggesting Eurasia as the place of origin, can be seen from six pollen taxa: (1) A Flueggea-type, together with previously found European Flueggea fossils, (2) a Nyssa-type closely resembling the extant Nyssa sinensis and upper Eocene Nyssa pollen from Europe, (3) three Symplocos-types, which are closely related to the early diverging Symplocos subgenus Palura, resemble upper Eocene Symplocos pollen from Germany, and (4) a Cornus-type belonging to the “blue-or-white-fruited clade,” like several Cornus fossils from Europe. In contrast, an Asian paleobiogeographic pattern can be seen from six Hainan taxa: (1) Two Phyllanthus subgen. Eriococcus/Isocladus-types, here described for the first time, that, so far, occur only in China, (2) a Lagerstroemia-type that resembles pollen of the Miocene Lagerstroemia cathayensis from China and pollen of two extant deciduous Lagerstroemia taxa, (3) a Juglans-type that is assumed to belong to Juglans section Cardiocaryon, and (4) two Dipterocarpaceae pollen types (cf. Dipterocarpus and cf. Dryobalanops) that are here described for the first time from Eocene strata outside India. A much wider distribution can be observed with the Fagus-type pollen closely resembling pollen of the extant Fagus “subgenus Engleriana” and Paleogene Fagus pollen from Greenland and Canada, suggesting an amphipacific distribution of an ancient Fagus “Engleriana lineage” during the Eocene. The Craigia-type corroborates the presence of Craigia diaspores from the Changchang Formation and two Mortoniodendron-types reveal a particular paleobiogeographical history; extant Mortoniodendron grows in Central America and is known there since the Miocene. However, Eocene Mortoniodendron-type pollen from Europe and now Hainan indicate a far wider distribution of this genus. The two Iodes types, one resembling African/Madagascar taxa and one a Melanesian taxon, suggest that the Old World disjunction of Iodes in Africa/Madagascar and SE Asia is a Paleogene relict, whereas the third Icacinaceae taxon resembles two genera of the Mappia/Nothapodytes clade, where Mappia occurs today in Central America and Nothapodytes in SE Asia.
       
  • Palynology of Middle Stone Age spring deposits in grassland at the
           Florisbad hominin site, South Africa
    • Abstract: Publication date: Available online 15 March 2019Source: Review of Palaeobotany and PalynologyAuthor(s): L. Scott, A.C. van Aardt, J.S. Brink, M.B. Toffolo, J. Ochando, J.S. Carrión New pollen evidence and a review of past palynological research at the Pleistocene Florisbad thermal spring mound, which produced faunal, hominin and archeological remains, allow a reconstruction of past conditions in the central Free State grassland, South Africa. Pollen sequences at the spring consist of alternating pollen-rich organic peaty horizons interrupted by hiatuses or pollen-poor layers of sandy and clayey deposits. The paleoclimatic interpretation of pollen sequences in springs like Florisbad, which contain a mixture of local and regional pollen and are influenced by spring mound cycles and changes in swamp configuration, requires consideration of taphonomy and site geomorphology to separate local from regional influences. By correlating the pollen stratigraphy in different parts of the site we suggest that the lower layers containing the Florisbad hominin (dated to 259 ka) and its associated Middle Pleistocene fauna, experienced cool moist and grassy conditions. Dating of some of the overlying Middle Stone Age layers suggest that they encompass the Last Interglacial period (MIS 5e; ca. 124–119 ka). In these levels the pollen evidence of upland fynbos shrubs unexpectedly suggests that cool conditions prevailed. This raises questions about the taphonomy, precision of the age estimate of occupation or the way we interpret pollen spectra.
       
  • Pollen, δ15N and δ13C guano-derived record of late Holocene vegetation
           and climate in the southern Carpathians, Romania
    • Abstract: Publication date: Available online 15 March 2019Source: Review of Palaeobotany and PalynologyAuthor(s): Daniel Martin Cleary, Angelica Feurdean, Ioan Tanțău, Ferenc L. Forray Two cores of bat guano were recovered from Topolnița and Gura Ponicovei Caves in the south-west region of Romania and analyzed for δ15N, δ13C and pollen. Deposition of guano began in CE 1537 at Gura Ponicovei and CE 1694 at Topolnița, allowing for the development and interpretation of climate and vegetation records since the Little Ice Age. δ15N values were found to record phases of the North Atlantic Oscillation through the effect of winter precipitation on the local nitrogen cycle. Alternatively, δ13C values are interpreted to correspond with variation in summer precipitation. Both records suggest progressively drier conditions during the termination of the LIA in the region at CE 1870. The transition to landscape openness, with patchy forests of Tilia, Carpinus betulus, and Quercus during this time could be related to the lower water availability at both sites. Wetter conditions inferred from a 3‰ increase in δ15N values between CE 1879 and CE 1970 occurred contemporaneously with a similar trend in European winter precipitation and increased frequency of positive NAO phases during this interval. The δ13C values between CE 1885 and CE 1968 suggest a trend towards a wetter summer climate as well. Although there is at times evidence of forest dynamics being controlled by climate, vegetation appears to be more closely associated with human impact, particularly around Topolnița Cave. With contributions of ruderal pollen indicators from CE 1985 – present is likely related to agricultural practices that were absent around Gura Ponicovei.
       
 
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