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  • 1.
    Andersson, Ulf Bertil
    et al.
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Jansson, Nils
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Wickström, Linda
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Bergman, Stefan
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Kumpulainen, Risto
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Johnson, Mark
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Olvmo, Mats
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology. Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Calner, Mikael
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Emendment to the term complex in: “Guide for geological nomenclature in Sweden” (Kumpulainen 2016)2022In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 144, no 3-4, p. 151-151Article in journal (Other academic)
    Abstract [en]

    Since the publication of Kumpulainen (2016), the Committeehave been alerted by the investigation and subsequent changesto the North American Stratigraphic Code concerning thelithodemic unit“complex”(Easton et al.2016; North Ameri-can Commission on Stratigraphic Nomenclature (NACSN)2017). These changes concern the introduction of the nomen-clature unit“Intrusive Complex”. In the original version(NACSN1983), as well as in the Swedish Guide for nomencla-ture (Kumpulainen2016), the unit“complex”is defined ascontaining at least two genetic classes of rocks, i.e., igneous,sedimentary, or metamorphic.

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  • 2. BADAWY, AHMED SALAH
    et al.
    Mehlqvist, Kristina
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology.
    Ahlberg, Per
    Calner, Mikael
    Late Ordovician (Katian) spores in Sweden: oldest land plant remains from Baltica2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 1, p. 16-21Article in journal (Refereed)
    Abstract [en]

    A palynological study of the Ordovician–Silurian boundary (Katian–Rhuddanian) succession in the Röstaånga-1 drillcore, southern Sweden, has been performed. The lithology is dominated by mudstone and graptolitic shale, with subordinate limestone, formed in the deeper marine halo of southernBaltica. The palynological assemblages are dominated by marine microfossils, mainly chitinozoans and acritarchs. Sparse but well-preserved cryptospores, including Tetrahedraletes medinensis, Tetrahedraletes grayii and Pseudodyadospora sp., were encountered in the Lindegård Formation (late Katian–early Hirnantian), with the oldest record just above the first appearance of the graptolite species Dicellograptus complanatus. This represents the earliest record of early land plant spores from Sweden and possibly also from Baltica and implies that land plants had migrated to the palaeocontinent Baltica by at least the Late Ordovician.

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  • 3.
    Bergström, Jan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Hou, Xian-Guang
    Yunnan University, Kunming.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    Gut contents and feeding in the Cambrian arthropod Naraoia2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, p. 71-76Article in journal (Refereed)
  • 4.
    Billström, Kjell
    et al.
    Swedish Museum of Natural History, Department of Geology. Department of Geological Sciences, Swedish Museum of Natural History, Stockholm, Sweden.
    Söderhielm, Johan
    Geological Survey of Sweden, Malå Office, Uppsala, Sweden.
    Broman, Curt
    Department of Geological Sciences, Stockholm University, Stockholm, Sweden.
    Sundblad, Krister
    Institute of Earth Sciences, Saint Petersburg State University, St Petersburg, Russia.
    Solstad, a Co-Se-bearing copper ore in the Västervik quartzites, Sweden2022In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, p. 1-14Article in journal (Refereed)
  • 5.
    Denk, Thomas
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bouchal, Johannes M.
    Dispersed pollen and calyx remains of Diospyros (Ebenaceae) from the middle Miocene “Plant beds” of Søby, Denmark2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, p. 292-304Article in journal (Refereed)
    Abstract [en]

    Diospyros is a large genus of woody flowering plants with a predominantly subtropical and tropical modern distribution. Fossils attributed to Diospyros are mainly leaf impressions from Cretaceous and Cenozoic strata across the Northern Hemisphere. However, it is difficult to assign such fossils to Diospyros because genus-diagnostic leaf characteristics remain to be identified. Unequivocal fossil records of Diospyros are few, including staminate flowers with in situ pollen from the late Eocene of South Australia and dispersed pollen from Cenozoic strata in the Northern Hemisphere. Here, we investigated dispersed pollen and calyx remains from Miocene deposits of Denmark using a combined scanning electron/light microscopy approach. Tricolporate, relatively large pollen with lalongate pori and longbow-shaped colpi and a distinctive micro/nanorugulate exine ornamentation together with persistent 4-lobed flower calyces allow unambiguous identification of the genus. Based on the large size of the calyx, we describe a new fossil-species of Diospyros. Further, a review of the fossil pollen record of Diospyros shows that, in addition to the Australian record, the genus was present in South China, western North America and Europe during the Eocene and in East and South Africa and Central Asia during the Oligo-Miocene. Although still scanty, the pollen record can contribute vital information for time calibrated molecular phylogenies to resolve conflicting biogeographic inferences. A thorough description of the historical biogeography of Diospyros is still in its infancy. While we initiate such a study here, development of a comprehensive picture will require further studies of dispersed pollen grains with high taxonomic resolution.

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  • 6.
    Devaere, Léa
    et al.
    Univ. Lille, CNRS, UMR 8198 – Evo-Eco-Paleo, Lille, France.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    The youngest known tommotiid: Lapworthella bornholmiensis (Poulsen, 1942) from Cambrian Stage 4 to Guzhangian (Miaolingian) strata of Bornholm and southern Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 151-167Article in journal (Refereed)
    Abstract [en]

    The Camenellan tommotiid Lapworthella bornholmiensis is systematically revised based on the original type material and collections of Small Shelly Fossils at the Swedish Museum of Natural History. The species is clearly differentiated from all other species of Lapworthella by its unique surface ornamentation. Variability in sclerite shape is analyzed among the 39 specimens and four sclerite morphotypes are recognized: bilaterally subsymmetrical A sclerites with straight apertural margin and subrectangular to subelliptical cross-section; asymmetrical B sclerites with oblique to curved apertural margin and subrectangular to subelliptical cross-section; asymmetrical C sclerites with one concave surface resulting in elliptical to sub-triangular cross section; elongated asymmetrical D sclerites with subcircular cross section. The C sclerites are further divided into two sub-types. The sclerite morphotypes of Lapworthella bornholmiensis allow a detailed comparison with other lapworthellid taxa and we identify a pattern of recurring sclerite morphotypes across a range of species, allowing a new understanding of the lapworthellid scleritome structure. The stratigraphic range of Lapworthella bornholmiensis includes the Cambrian Stage 4 Gislöv Formation, the Wuliuan-Drumian Forsemölla and Exsulans Limestones in the Alum Shale Formation and Guzhangian limestone fill in Proterozoic basement fissures in Bohuslän, making this long ranging species the youngest known tommotiid in the fossil record.

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  • 7.
    Hagenfeldt, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Palmlöv, Erik
    Svenska Petroleum Exploration AB.
    Amantov, Aleksey
    cA.P. Karpinsky Russian Geological Research Institute (VSEGEI).
    Hagström, Jonas
    Swedish Museum of Natural History, Department of Paleobiology.
    Ghalayini, Rémy
    Agenor Energy.
    Liljedahl, Thomas
    WSP Sverige AB.
    The development of dark shales from the middle and late Cambrian to early Ordovician on the East European Platform – with focus on Gotland2023In: GFF, ISSN 1103-5897, E-ISSN 2000-0863Article in journal (Refereed)
    Abstract [en]

    By compiling data from literature and unpublished reports a more detailed description is presented on the geographical and stratigraphic distribution of the Alum Shale Formation (ASF) and correlateable units on the East European Platform. In the northern part of Gotland, downfaulted patchy beds of the ASF indicate a former wider extension of the formation. Lower Ordovician (Tremadocian) examples of downfaulted patchy beds are the contemporaneous Sepopol and Nivenskaya formations in northeastern Poland and the Kaliningrad area, as well as the Salantai Formation in the east Baltic area. It is indicated that Furongian-Tremadocian beds, contemporaneous with the Kallavere, Türisalu, Tosna and Koporye formations, in the area of northern Estonia and the northwestern part of the Moscow Basin, extended to the Gotland and the South Bothnian Basin areas. South of Gotland, in the Swedish sector of the Baltic Basin, drill cores show evidence of tectonic movements through the presence of erosional surfaces indicating occasional subaerial exposure. In this region, variations in the areal extent and thickness of the ASF and coeval formations are suggested to be the result of epeirogenic and tectonic block movements. Tremadocian ASF is also indicated to be present south of Gotland. On Gotland, at least 5 m of the ASF is presumed to have been eroded. The Moscow Basin contains 19 m of dark shales (Koporye Formation) which is significantly thicker than in surrounding areas.

  • 8.
    Holtstam, Dan
    Swedish Museum of Natural History, Department of Geology. Swedish Museum of Natural History.
    Prehistory of an enigmatic mineral: hisingerite2023In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 145, p. 1-3Article in journal (Refereed)
    Abstract [en]

    According to most sources, the type locality for the hydrous iron silicate mineral hisingerite is Riddarhyttan, Västmanland, Sweden, first reported in 1828. However, it was described by A.F. Cronstedt as early as 1751 from Väster Silvberg, Dalarna (under the name “kolspeglande järnmalm”), and in 1810 by W. Hisinger from the Gillinge iron mine, Södermanland (“svart stenart”, later “gillingit”). J. Berzelius introduced the presently valid species name (originally spelt “hisingrit”) in 1819. Potential type materials are preserved by the Swedish Museum of Natural History, from Gillinge and Riddarhyttan. A Hisinger specimen from Gillinge has recently been analysed and was shown to contain associated potassic-hastingsite, magnetite and fayalite that explain the previously observed aluminium contents and high density for “gillingit”, compared to pure hisingerite

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  • 9.
    Holtstam, Dan
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Bindi, Luca
    University of Florence.
    Karlsson, Andreas
    Swedish Museum of Natural History, Department of Geology.
    Söderhielm, Johan
    Sveriges Geologiska Undersökning.
    Zetterqvist, Anders
    Zetterqvist Geokonsult AB, Bromma, Sweden.
    Muonionalustaite, Ni3(OH)4Cl2·4H2O, a new mineral formed by terrestrial weathering of the Muonionalusta iron (IVA) meteorite, Pajala, Norrbotten, Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 1, p. 1-7Article in journal (Refereed)
    Abstract [en]

    Muonionalustaite, ideally Ni3(OH)4Cl2·4H2O, is a new mineral species (IMA 2020-010), found as a terrestrial weathering product of the Muonionalusta iron meteorite, in a fragment excavated 1.5 km NE of Lake Kitkiöjärvi. Muonionalustaite occurs in cavities of corrosion crust, associated with taenite, goethite, maghemite, amorphous Fe-Ni oxy-hydroxides and soil mineral particles. The mineral is green in colour and transparent. It occurs as lath-like crystals up to ca. 5 μm, elongated along [010] and flattened on {001}, forming aggregates and thin crusts. The calculated density and overall refractive index are 2.67(1) g·cm-3 and 1.68, respectively. An empirical formula from point analyses is (Ni2.88Fe0.02S0.02Al0.01Si0.012.94(OH3.73Cl2.276.00·4H2O. The crystal structure was refined in the space-group C2/m from powder X-ray diffraction data to RBragg = 3.55%. The monoclinic unit-cell parameters are a = 15.018(3) Å, b = 3.1490(6) Å, c = 10.502(3) Å, β = 101.535(15)º and V = 486.62(19) Å3 for Z = 2. Muonionalustaite is isostructural with the synthetic compounds Ni3(OH)3.9Cl2.1·4H2O and Mg3(OH)4Cl2·4H2O. The strongest X-ray diffraction lines are [I(%), d(Å), hkl]: 100, 10.30, 001; 67, 5.49, 201; 31, 3.868, 202; 30, 7.36, 200 and 25, 2.409, 60-2. Raman spectra show prominent bands at 3624, 3612, 3571 and 3507 cm-1, respectively, related to O–H-stretching vibrations of OH- groups, and in the region 450–530 cm-1 representing metal–O(H) vibration modes.

  • 10.
    Holtstam, Dan
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Söderhielm, Johan
    Sveriges Geologiska Undersökning.
    An 18th century find of an erratic lazulite-andalusite-quartz boulder in Södermanland, Sweden, and its implications2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 141, no 3, p. 216-221Article in journal (Refereed)
    Abstract [en]

    At some point in the 1750s, a jeweller-apprentice by the name Jacob Hässelgren found an erratic bouldernext to the Eskilstuna country road in the neighbourhood of Ärla in Södermanland. It contained a deep bluemass of lazulite, at the time an unknown mineral. Pieces of the find eventually reached Daniel Tilas, TorbernBergman and Axel Fredrik Cronstedt ˗ renowned natural scientists in Sweden ˗ but no detailed studies of thematerial seem to have been carried out by them. Two fragments of the original boulder are still preserved,and a recent examination shows them to consist of mainly lazulite, andalusite, quartz, pyrophyllite, augeliteand svanbergite. The average composition of lazulite is Mg0.700Fe2+0.261Mn0.003Al1.954Fe3+0.017 P2.031O8(OH)2.The mineral assemblage is characteristic of known occurrences of phosphate-Al silicate-quartz appearingalong the Protogine Zone in southern Sweden. Transportation of the boulder from its source rock, likely tobe located somewhere along the Protogine Zone, ought to have occurred in connection with the developmentof the Fennoscandian ice sheet during the final Weichselian deglaciation, and the material waspossibly discharged from floating ice on the Yoldia Sea.

  • 11.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Drake, Henrik
    Linnaeus University Faculty of Health and Life Sciences, Kalmar, Sweden.
    Neubeck, Anna
    Swedish Museum of Natural History, Department of Paleobiology. Uppsala University.
    Snoeyenbos-West, Oona
    Swedish Museum of Natural History, Department of Paleobiology. Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
    Belivanova, Veneta
    Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Introducing palaeolithobiology2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 305-319Article in journal (Refereed)
    Abstract [en]

    A growing literature of deep but also surficial fossilized remains of lithobiological life, often associated with igneous rocks, necessitates the unfolding of a sub-discipline within paleobiology. Here, we introduce the term paleolithobiology as the new auxiliary sub-discipline under which fossilized lithobiology should be handled. We present key criteria that distinguish the paleolithobiological archive from the traditional one and discuss sample strategies as well as scientific perspectives. A majority of paleolithobiological material consists of deep biosphere fossils, and in order to highlight the relevance of these, we present new data on fungal fossils from the Lockne impact crater. Fungal fossils in the Lockne drill cores have been described previously but here we provide new insights into the presence of reproductive structures that indicate the fungi to be indigenous. We also show that these fungi frequently dissolve and penetrate secondary calcite, delineating the role lithobionts plays in geobiological cycles. We hope that the formalization of the sub-discipline paleolithobiology will not only highlight an overlooked area of paleobiology as well as simplify future studies of endo- and epilithic fossil material, but also improve our understanding of the history of the deep biosphere.

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  • 12.
    Jadwiszczak, Piotr
    et al.
    Faculty of Biology, University of Bialystok, Bialystok, Poland.
    Reguero, Marcelo
    Instituto Antártico Argentino, Campus Miguelete, Buenos Aires, Argentina.
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    A new small-sized penguin from the late Eocene of Seymour Island with additional material of Mesetaornis polaris2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 283-291Article in journal (Refereed)
    Abstract [en]

    Here, we report on two tarsometatarsi assignable to relatively small-sized Eocene Antarctic penguins, housed in the palaeozoological collections of Naturhistoriska riksmuseet, Stockholm. The Priabonian fossils were collected by museum staff during two joined Argentinean and Swedish expeditions from the Submeseta Formation on Seymour Island, Antarctic Peninsula. One specimen represents a new early sphenisciform, Marambiornopsis sobrali gen. et sp. nov., the sixth small-sized tarsometatarsus-based penguin species known from the Antarctic Eocene. Micro-CT scanning revealed the presence of quite large and essentially empty metatarsal medullary cavities. The second fossil can unequivocally be assigned to Mesetaornis polaris. The specimen represents only the second record of this species and supposedly a relatively young bird. Micro-CT scanning showed that in M. polaris the metatarsal medullary cavities are less developed than in M. sobrali – the cortical and trabecular bone tissues left rather little room for significant hollow spaces. Both specimens also differ in overall density of their trabecular networks.

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  • 13.
    Jarochowska, Emilia
    et al.
    GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, University of Erlangen-Nürnberg, Erlangen, Germany.
    Bremer, Oskar
    Department of Organismal Biology, Uppsala University, Uppsala, Sweden.
    Yiu, Alexandra
    GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, University of Erlangen-Nürnberg, Erlangen, Germany.
    Märss, Tiiu
    Department of Geology, Tallinn University of Technology, Tallinn, Estonia.
    Blom, Henning
    Department of Organismal Biology, Uppsala University, Uppsala, Sweden.
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology. Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Revision of thelodonts, acanthodians, conodonts, and the depositional environments in the Burgen outlier (Ludlow, Silurian) of Gotland, Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 168-189Article in journal (Refereed)
    Abstract [en]

    Ludfordian strata exposed in the Burgen outlier in eastern Gotland, Sweden record a time of initial faunal recovery after a global environmental perturbation manifested in the Ludfordian Carbon Isotope Excursion (LCIE). Vertebrate microfossils in the collection of the late Lennart Jeppsson, hosted at the Swedish Museum of Natural History, hold the key to reconstruct the dynamics of faunal immigration and diversification during the decline of the LCIE, but the stratigraphic relationships of the strata have been debated. Historically, they had been placed in the Burgsvik Formation, which included the Burgsvik Sandstone and the Burgsvik Oolite members. We revise the fauna in the Jeppsson collection and characterize key outcrops of Burgen and Kapellet. The former Burgsvik Oolite Member is here revised as the Burgen Oolite Formation. In the Burgenoutlier, back-shoal facies of this formation are represented and their position in the Ozarkodina snajdri Biozone is supported. The shallow-marine position compared to the coeval strata in southern Gotland isreflected in the higher δ13C carb values, reaching +9.2‰. The back-shoal succession includes high-diversity metazoan reefs, which indicate a complete recovery of the carbonate producers as the LCIE declined. The impoverishment of conodonts associated with the LCIE in southern Gotland might be a product of facies preferences, as the diverse environments in the outlier yielded all 21 species known from the formation. Fish diversity also returned to normal levels as the LCIE declined, with a minimum of nine species. In line with previous reports, thelodont scales appear to dominate samples from the Burgen outlier.

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  • 14.
    Johansson, Åke
    Swedish Museum of Natural History, Department of Geology.
    A refined U-Pb age for the Stockholm granite at Frescati, east-central Sweden2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 141, no 1, p. 40-47Article in journal (Refereed)
    Abstract [en]

    A sample of fine-grained grey Stockholm granite from the Frescati area just north of central Stockholm, east-central Sweden, earlier dated to 1803 +23/−19 Ma by the U-Pb zircon method using TIMS on multigrain fractions, has been reanalyzed using the Nordsim ion microprobe. The new age obtained, 1792±4 Ma, is more precise, and replaces the earlier highly discordant date. It agrees well with other ages for the formation of the Stockholm-type granites and related pegmatites, indicating an age of around 1.79 Ga for this late-orogenic Svecofennian granite magmatism. The Stockholm granite thus formed toward the end of the 1.83–1.79 Ga late Svecofennian metamorphic phase, and crosscuts earlier formed migmatitic gneiss structures in a brittle manner at the present-day level of exposure.

  • 15.
    Johansson, Åke
    Swedish Museum of Natural History, Department of Geology. Swedish Museum of Natural History.
    Cleaning up the record – revised U-Pb zircon ages and new Hf isotope data from southern Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 4, p. 328-359Article in journal (Refereed)
    Abstract [en]

    Ten samples of orthogneisses and granitoids from the Eastern Segment of the Sveconorwegian Orogen in southern Sweden, previously dated by ID-TIMS on zircon, have been dated anew using SIMS spot analysis of individual zircon grains, leading to more reliable and in most cases also more precise revised magmatic crystallization ages. A gneissic monzonite within the Protogine Zone south of Alvesta in Småland yields a revised U-Pb age of ca. 1725 Ma, four samples of orthogneiss from Skåne all yield revised ages between 1690 and 1700 Ma, while two samples of coarse-grained granitoid gneiss in the same region yield ages between 1680 and 1690 Ma. These revised ages are between 15 and 250 m.y. older than previously obtained TIMS ages. Two samples of the Gumlösa-Glimåkra granite along the Protogine Zone in northern Skåne and one sample of related syenite yield ages around 1220 Ma, similar but more precise compared to the previous ages. The U-Pb zircon data have been complemented by Hf isotope analysis by LA-ICP-MS on the same zircon grains, and previously obtained initial Sr and Nd whole-rock isotope data have been recalculated to the revised crystallization ages. The Sr isotope data scatter, while the revised initial εNd values fall between +1 and +2 for the older granitoids and orthogneisses, and close to 0 for the 1220 Ma intrusives along the Protogine Zone. Initial εHf in magmatic undisturbed zircons shows relatively little spread within each sample, between 2 and 4 Epsilon units, disregarding occasional outliers, with average values for the 1725 - 1680 Ma rocks falling between +3and +5.5, and at ca. +1.5 in the 1220 Ma rocks. In spite of the limited variation, there is a covariation between initial εNd and initial εHf in the older rocks, suggesting either mixing between two isotopically distinct magma sources, or one magma source which is isotopically heterogeneous. The isotopic signatures of the 1220 Ma intrusives along the Protogine Zone is indicative of juvenile mantle input totheir magmas, rather than pure crustal melting.

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    Cleaning up the record (Submitted version)
  • 16.
    Johansson, Åke
    Swedish Museum of Natural History, Department of Geology.
    U-Pb SIMS dating of some granitoids from eastern Blekinge, southern Sweden2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 3, p. 430-444Article in journal (Refereed)
    Abstract [en]

    Zircons from seven granitoids in eastern Blekinge have been dated using secondary ion mass spectrometry. The analyzed rocks include one Småland granitoid from north of the Småland-Blekinge Deformation Zone (SBDZ), two samples of megacrystic “Filipstad-type” granite from south of that zone, and one sample each of the “Småland-type” Rödeby, Almö, Tjurkö and Jämjö granites. The results yield a crystallization age of 1776 ± 6 Ma for the Småland granitoid, and crystallization ages between 1770 ± 4 and 1758 ± 6 Ma for the other granitoids, in most cases substantially older than previous TIMS ages. These data show that the “Småland-type” granitoids in eastern Blekinge are similar in age to the surrounding Tving granitoids, and the more felsic of them may represent late-stage differentiates belonging to the same magmatic suite. As the Tving granitoids show differences both in degree of deformation, in geochemistry and possibly in age, when compared with the Småland granitoids north of the SBDZ, it is suggested that these represent two separate but closely related igneous suites, which could both be included within a TIB-1 supersuite.

    The investigated zircons showed very limited signs of metamorphic overgrowths, and no metamorphic ages could be determined. However, the combined evidence from field observations combined with earlier U-Pb geochronology would suggest the presence of two separate metamorphic episodes in Blekinge, one in close connection with the formation of these rocks at 1.76 – 1.75 Ga, and one connected to the intrusion of the Karlshamn granitoid suite at around 1.45 Ga.

  • 17.
    Johansson, Åke
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Andersen, Tom
    Universitetet i Oslo.
    Simonsen, Siri L.
    Universitetet i Oslo.
    Hafnium isotope characteristics of late Palaeoproterozoic magmatic rocks from Blekinge, southeast Sweden: possible correlation of small-scale Hf and Nd isotope variations in zircon and whole-rocks.2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 1, p. 74-82Article in journal (Refereed)
  • 18.
    Johansson, Åke
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Karlsson, Andreas
    Swedish Museum of Natural History, Department of Geology.
    The “intraorogenic” Svecofennian Herräng mafic dyke swarm in east-central Sweden: age, geochemistry and tectonic significance2020In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 142, no 1, p. 1-22Article in journal (Refereed)
    Abstract [en]

    The Herräng mafic dykes form an E-W-trending dyke swarm within the Bergslagen lithotectonic unit of the Svecofennian orogen in east-central Sweden. They intrude the Svecofennian supracrustal rocks and early-orogenic granitoids, but are themselves cut by late Svecofennian pegmatites, and have undergone Svecofennian amphibolite-facies metamorphism, leading to their classification as ‘intraorogenic’ Svecofennian dykes. They can be assigned an age between 1870 and 1850 Ma, with metamorphism of the dykes dated at 1848 ± 13 Ma by U-Pb in titanite. Their current mineralogy is dominated by metamorphic plagioclase and amphibole, with variable amounts of quartz and biotite, and minor to accessory titanite, apatite, epidote, pyrite, magnetite, ilmenite and zircon. Textures range from massive to strongly foliated.

    Twenty samples of dyke rocks from three subareas in the Roslagen region, including the Herräng type area, range in composition from basaltic to andesitic with 47 to 60 wt% SiO2, broadly similar to the Dannemora dykes and the Avesta-Östhammar gabbros and diorites. Initial 87Sr/86Sr ratios (at 1870 Ma) varies between 0.7026 and 0.7038, corresponding to initial εSr between +5 and +21, and initial εNd between -0.4 and +1.3, suggesting a slightly enriched to mildly depleted mantle source, similar to other Svecofennian mafic rocks.

    The dykes dominantly show a calc-alkaline volcanic arc signature related to subduction. They formed during an extensional episode, possibly related to incipient back-arc spreading or subduction roll-back following the main early-orogenic subduction-related Svecofennian magmatism, but penecontemporaneous with amphibolite-facies metamorphism in the area.

  • 19.
    Jonsson, Erik
    et al.
    Sveriges Geologiska Undersökning, Uppsala.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    Mn3+-bearing pargasite from the Långban Fe-Mn oxide mineralisation, Bergslagen, Sweden2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, p. 167-172Article in journal (Refereed)
  • 20.
    Krüger, Ashley
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Swedish Museum of Natural History.
    Slater, Sam M
    Swedish Museum of Natural History, Department of Paleobiology.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    3D imaging of shark egg cases (Palaeoxyris) from Sweden with new insights into Early Jurassic shark ecology2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 229-247Article in journal (Refereed)
    Abstract [en]

    Several shark species produce egg cases as protective casings in which their embryos develop. These casings are composed of multiple layers of collagen and are extremely durable, making them prone to fossilisation. Here we document Palaeoxyris (Spirangium) ‒ fossil shark egg cases from Lower Jurassic successions of southern Sweden. We present high-resolution 3D images of Palaeoxyris based on microfocus X-ray computed tomography (μCT) of seven specimens, including fossils that were embedded within a sandstone matrix. Our examination of the internal structure of the egg cases revealed the possible remnants of a yolk and foetus in one specimen. The cases were most likely produced by hybodont sharks, as outlined in previous studies, and the occurrence of hybodont teeth from Lower Jurassic successions of Sweden support this. Palynological analysis of the matrix from one of the specimens hosting Palaeoxyris, indicates an early Hettangian age. The high percentage of spores (c. 60%) reveals that the egg cases were laid during the Transitional Spore Spike Interval following the end-Triassic mass extinction. The egg cases are found in conjunction with fossil horsetails; with the broader palynological and sedimentological evidence, this suggests an estuarine depositional setting, and potentially indicates that newborn sharks were living in habitats comparable to modern mangroves, as is often the case today.

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  • 21.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Marine and terrestrial invertebrate borings and fungal damage in Paleogene fossil woods from Seymour Island, Antarctica2020In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 142, no 3, p. 223-236Article in journal (Refereed)
    Abstract [en]

    An assemblage of permineralized conifer and angiosperm woods collected from Paleogene marine strataon Seymour Island during the Swedish Antarctic expedition of 1901–1903 includes many specimens with internal damage caused by an array of xylophagous organisms. Short, broad, clavate borings referable to Gastrochaenolites clavatus are attributed to pholadid bivalves. Elongate borings with carbonate linings referable to Apectoichnus longissimus were produced by teredinid bivalves. Slender, cylindrical tunnels cross-cutting growth rings and backfilled in meniscoid fashion by frass composed of angular tracheid fragments were probably produced by a terrestrial beetle borer. They are most similar to tunnels generated by modern cerambycid and ptinid coleopterans. Less regular, spindle-shaped cavities and degraded zones flanking growth rings are similar to fungi-generated modern white pocket rot. Larger chambers in the heartwood referable to the ichnotaxon Asthenopodichnium lignorum were produced by an alternative mode of fungal degradation. The biological interactions evident in the fossil woods illustrate additional terrestrial trophic levels enhancing the known complexity of ecosystems on and around the Antarctic Peninsula shortly before the initial pulse of mid-Cenozoic glaciation in Antarctica that caused extirpation of the majority of plants and animals in that region.

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  • 22.
    McLoughlin, Stephen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Halamski, Adam T.
    Institute of Paleobiology, Polish Academy of Sciences, Warszawa, Poland.
    Mays, Chris
    Swedish Museum of Natural History, Department of Paleobiology.
    Kvacek, Jiří
    National Museum, Praha, Czech Republic.
    Neutron tomography, fluorescence and transmitted light microscopy reveal new insect damage, fungi and plant organ associations in the Late Cretaceous floras of Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 248-276Article in journal (Refereed)
    Abstract [en]

    Neutron tomographic reconstructions, macrophotography, transmitted light microscopy and fluorescence microscopy are employed to assess the quality of organic preservation, determine organ associations,identify insect damage, and document fungal interactions with selected Santonian–lower Campanian plant fossils from the northern Kristianstad Basin, southern Sweden. Fricia nathorstii (Conwentz) comb. nov., is proposed for a composite fossil comprising an anatomically preserved (permineralized) cupressacean conifer cone and its subtending, concealed, leafy axis (preserved asa mould) in the Ryedal Sandstone. Several other impressions of conifer and angiosperm leaf-bearing axes and isolated leaves are described under open nomenclature. Three cuticle types are described from the non-marine plant-bearing beds in the basal part of the succession exposed at Åsen, but these are only assigned to informal morphotypes pending a comprehensive review of the extensive fossil cuticle flora. Two species of ascomycote epiphyllous fungi from Åsen are established: Stomiopeltites ivoeensis sp. nov. (Micropeltidales) and Meliolinites scanicus sp. nov. (Meliolales). The latter provides an important calibration point for dating the divergence of Meliolales, being the first pre-Cenozoic representative of the order. Various additional fungal remains, including thyriothecia, scolecospores, chlamydospores, putative germlings, and hyphae, are described from the cuticular surfaces of conifer and angiosperm leaves from Åsen. Insect herbivory is expressed in the form of both margin-feeding and piercing-and-sucking damage on angiosperm leaves. The Santonian–early Campanian vegetation is inferred to have grown in strongly humid, mid-latitude, coastal plain settings based on the depositional context of the assemblages, leaf morphology, and the pervasive distribution of epiphyllous fungi.

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  • 23.
    McLoughlin, Stephen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Topper, Timothy
    Swedish Museum of Natural History, Department of Paleobiology.
    Crowley, James L.
    Isotope Geology Laboratory, Boise State University, Boise, ID, USA.
    Liu, Fan
    Swedish Museum of Natural History, Department of Paleobiology. Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden;State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life and Environments and Department of Geology, Northwest University, Xi’an, China.
    Johansson, Ove
    Swedish Museum of Natural History, Department of Paleobiology. Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Trace fossils, algae, invertebrate remains and new U-Pb detrital zircon geochronology from the lower Cambrian Torneträsk Formation, northern Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 103-133Article in journal (Refereed)
    Abstract [en]

    Nineteen ichnotaxa, together with algal and invertebrate remains, and various pseudo-traces and sedimentary structures are described from the Torneträsk Formation exposed near Lake Torneträsk, Lapland, Sweden, representing a marked increase in the diversity of biotic traces recorded from this unit. The “lower siltstone” interval of the Torneträsk Formation contains mostly simple pascichnia, fodinichnia and domichnia burrows and trails of low-energy shoreface to intertidal settings. The assemblage has very few forms characteristic of high-energy, soft-sediment, foreshore or upper shoreface environments (representative of the Skolithos ichnofacies).

    Uranium-lead (U-Pb) LA-ICPMS analysis of zircon from a thin claystone layer within the “lower siltstone” interval yielded a maximum depositional age of 584 ± 13 Ma, mid-Ediacaran. Most of the zircon is represented by rounded detrital grains that yield dates between 3.3 and 1.0 Ga. Although the age of the basal sandstone-dominated interval of the Torneträsk Formation remains elusive owing to the absence of fossils, the ichnofossil suite from the overlying “lower siltstone” interval lacks deep arthropod trackways, such as Rusophycus and Cruziana, and is suggestive of a very early (Terreneuvian, possibly Fortunian) Cambrian age. The ichnofauna is otherwise similar to early Cambrian trace fossil assemblages from other parts of Baltica, regions further south in modern Europe, and from Greenland.

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  • 24.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology.
    Cameral deposits in Paleozoic cephalopods2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 40, p. 254-263Article in journal (Refereed)
    Abstract [en]

    Calcareous cameral deposits have been described in several orthocerid and actinocerid nautiloids. According to the prevailing hypothesis, they were secreted during the lifetime of the animal, either by living tissues in the shell chambers, or by precipitation from the cameral liquid. In the present paper, cameral deposits are described in three species of Carboniferous orthocerid-like coleoid (Order Colorthocerida) from USA. The shell walls and septa in these coleoids are very thin and poorly calcified. In one half of the population of the three species, the septa are completely fragmented and there are no cameral deposits. In the other half of the population, the septa are partially fractioned and their surfaces are covered by welldeveloped cameral deposits. In contrast to the septa, the cameral deposits do not show any fractioning. To explain the origin of the cameral deposits, the following hypothetical scenario is the most realistic. After the death of the animals, the shells were accumulated on the sea floor and in one half of the population the septa became fully fractioned by the hydrostatic pressure. In shells of another half of the population, the septa were only partially fractioned. The calcifying bacteria entered the chambers of the dead shells through the porous connecting rings and gave rise to the cameral deposits.

  • 25.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    Characterization of two new superorders Nautilosiphonata and Calciosiphonata and a new order Cyrtocerinida of the subclass Nautiloidea: siphuncular structure in the Ordovician nautiloid Bathmocerass (Cerphalopoda)2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 3, p. 164-174Article in journal (Refereed)
    Abstract [en]

    Based on differences in the siphuncular structures, the subclass Nautiloidea is divided into two new superorders: Nautilosiphonata and Calciosiphonata. The first superorder is characterized by the nautilus-type of connecting rings, and the second superorder by calcified-perforate type of the connecting rings. A new order Cyrtocerinida is erected for the families Bathmoceratidae, Cyrtocerinidae and Eothinoceratidae, previously included in the order Ellesmeroceratida. The siphuncular structure in the Ordovician nautiloid Bathmocerasholmi n. sp. is described. It is characterized by (1) connecting rings that are composed of an outer, calcareous, spherulitic–prismatic layer and an inner, fibrous, chitinous layer, and (2) prominent siphuncular ridges that originate from the inner surfaces of the connecting rings. The structure of the siphuncular ridges in Bathmoceras is compared with that of the actinosiphonate lamellae in the Silurian oncocerid nautiloid Octamerella.

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  • 26.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology.
    Restudy of some plectronocerid nautiloids (Cephalopoda) from the late Cambrian of China; discussion on nautiloid evolution and origin of the siphuncle2020In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 142, no 2, p. 115-124Article in journal (Refereed)
    Abstract [en]

    The sub-class Nautiloidea is divided into two super-orders, Nautilosiphonata and Calciosiphonata, basedon different structural types of the connecting rings.The late Cambrian order Plectronocerida has the calciosiphonate type of connecting ring similar tothat in post-Cambrian orthocerids. It is structurally more complex than the nautilosiphonate connectingring in late Cambrian ellesemerocerid-like nautiloids. The plectronocerid nautiloids, therefore, evolvedfrom the ellesmerocerid-like nautiloids and not vice versa. As indicated by the complex siphuncularstructure in plectronocerids, cephalopod evolution began earlier than previously estimated, probably inthe early Cambrian. The siphuncle in cephalopods originated from a calcareous septum that becamepartially non-calcified and formed the connecting ring.

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  • 27.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    Siphuncular structure in the extant Spirula and in other coleoids (Cephalopoda)2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, no 2, p. 129-139Article in journal (Refereed)
    Abstract [en]

    The shell wall in Spirula is composed of prismatic layers, whereas the septa consist of lamello-fibrillar nacre. The septal neck is holochoanitic and consists of two calcareous layers: the outer lamello-fibrillar nacreous layer that continues from the septum, and the inner pillar layer that covers the inner surface of the septal neck. The pillar layer probably is a structurally modified simple prisma layer that covers the inner surface of the septal neck in Nautilus. The pillars have a complicated crystalline structure and contain high amount of chitinous substance. The interspaces between the pillars probably are traversed horizontally by numerous chitinous membranes like in the cuttlebone chambers in Sepia. The connecting ring is composed of similar two layers as that in the extant Nautilus: the outer spherulitic–prismatic layer and the inner chitinous layer. The spherulitic–prismatic layer takes its origin on the outer surface of the septal neck, whereas the inner chitinous layer is the non-calcified continuation of the lamello-fibrillar nacreous layer of the septal neck. The siphuncular structure in Spirula is compared with that in the extant Nautilus, fossil nautilosiphonate nautiloids, and five taxa of coleoids.

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  • 28.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology.
    Siphuncular structure in the Jurassic belemnitid Megateuthis (Cephalopoda, Coleoidea)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, p. 1-8Article in journal (Refereed)
  • 29.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    Siphuncular structures in Calciosiphonate nautiloid orders Actinocerida, Orthocerida and Barrandeocerida (Cephalopoda).2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 295-305Article in journal (Refereed)
  • 30.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    The new order Mixosiphonata (Cephalopoda: Nautiloidea) and related taxa; estimations of habitat depth based on shell structure2017In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, p. 219-232Article in journal (Refereed)
    Abstract [en]

    The new order Mixosiphonata is characterized by its siphuncular structure. The order contains the ectocochleate cephalopods Boggyoceras centrale n. gen. et n. sp. (Carboniferous) and Zhuravlevia insperata (Cretaceous); both are orthocones. The bactritoid-like coleoid Ctenobactrites lesliensis (Carboniferous) has a similar siphuncular structure and is therefore, provisionally included in this new order. In the new order Mixosiphonata, the proximal part of the septal neck has the same structure as the septum from which it originates, whereas the entire distal part is composed of prismatic and spherulitic layers embedded into a chitinous substance. Also the connecting ring consists of prisms and spherulites embedded into chitinous substance, but the calcareous elements are smaller than those in the distal part of the septal neck. The structure of the connecting ring and septal neck differs from the 13 types of siphuncular structures in nautiloids, ammonoids and coleoids that are currently known. The siphuncular structure in the Ordovician cephalopod Bactroceras avus is described and compared with that in the mixosiphonates. The shell strength indexes derived from the extant Nautilus cannot be used for estimations of habitat depth in most, if not all, known externally shelled cephalopods because in the fossil cephalopods the siphuncular structures are different from that of extant Nautilus, and therefore, the mechanical strength of the siphuncles in the fossil shells and Nautilus shell is not comparable.

  • 31.
    Mutvei, Harry
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Mapes, Royal H.
    bAmerican Museum of Natural History, New York, NY, USA.
    Carboniferous coleoids with mixed coleoid-orthocerid characteristics: a new light oncephalopod evolution2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 140, p. 11-24Article in journal (Refereed)
    Abstract [en]

    Orthocerid-like coleoids with mixed orthocerid-coleoid characteristics are described for the first time from the Carboniferous of USA. The appearance of these coleoids represents transitional morphology between the orthoconic nautiloid and coleoid lineages. This transitional state is based on the new genus Colorthoceras n. gen. with three assigned new species (C. inflata n. sp., C. tubulata n. sp. and C. concavus n. sp.) in the new family Colorthoceridae of the new order Colorthocerida. Orthocerid nautiloid characteristics include a longiconic phragmocone with a well-developed body chamber, and a central, sub-central or sub-ventral siphuncle with endosiphuncular deposits. The shell wall in the new order Colorthocerida is characterized by the coleoid characteristics of a lack of the nacreous layer, with a high content of chitin that created a somewhat semi-elastic shell. The connecting rings are uni-layered, directly continuous from the septal neck, and have a mixed chitinous-calcareous composition similar to that in order Mixosiphonata. The shell wall structure in these unique orthocerid-like coleoids is similar to that in the previously described Carboniferous bactritoid-like coleoids. The evolution of these coleoid characteristics appears to represent an unsuccessful evolutionary experiment, as the diversity of this nautiloid lineage was in gradual decline in the Upper Paleozoic.

  • 32.
    Mörs, Thomas
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Liu, Liping
    Swedish Museum of Natural History, Department of Paleobiology.
    Hagström, Jonas
    Swedish Museum of Natural History, Department of Paleobiology.
    A Miocene tetraconodontine (Suidae, Mammalia) from Falkenberg (Halland, Sweden)2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, p. 77-81Article in journal (Refereed)
  • 33.
    Peng, Jungang
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. aState Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing.
    Slater, Sam M
    Swedish Museum of Natural History, Department of Paleobiology.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Megaspores from the Late Triassic‒Early Jurassic of southern Scandinavia: taxonomic and biostratigraphic implications2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 202-228Article in journal (Refereed)
    Abstract [en]

    Here we investigate megaspores from 10 Triassic‒Jurassic localities of southern Sweden and Bornholm, Denmark, based on collections housed in the Swedish Museum of Natural History. We identify and describe 19 megaspore taxa belonging to three stratigraphically constrained assemblages, representing the Rhaetian, Hettangian and Pliensbachian, respectively. Megaspores are abundant and diverse (12 taxa) in the Rhaetian assemblage. Diversity markedly decreases across the Triassic–Jurassic boundary (TJB), with species richness reducing from 12 to two taxa. The Hettangian assemblage is well-preserved but depauperate, and is overwhelmingly dominated by Nathorstisporites hopliticus. A subsequent recovery of lycopsid diversity followed, recorded by an increase in richness to six taxa in the Pliensbachian assemblage. The disappearance of the hygrophilous and diverse heterosporous lycophyte communities acrossthe TJB, suggests a shift to drier conditions in the earliest Jurassic. This is supported by lithological changes from coal-forming environments in the Rhaetian to sandstone-dominated fluvial-estuarine facies in the Hettangian. Throughout this study, we analysed the megaspores using fluorescence microscopy, which revealed detailed morphological features on specimens that were otherwise opaque under visible light. This non-destructive technique is particularly useful for examining opaque megaspores embedded in permanent mounting media, such as epoxy resin, and may provide new insights into historical megaspore collections elsewhere.

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  • 34.
    Peng, Jungang
    et al.
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China;Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
    Slater, Sam M.
    Swedish Museum of Natural History, Department of Paleobiology.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology.
    Megaspores from the Late Triassic‒Early Jurassic of southern Scandinavia: taxonomic and biostratigraphic implications2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 202-228Article in journal (Refereed)
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  • 35.
    Petersson, Andreas
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Tual, Lorraine
    Swedish Museum of Natural History, Department of Geology.
    Zircon U-Pb-Hf isotope data in eclogite and metagabbro from southern Sweden reveal a common long-lived evolution and enriched source2020In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 142, no 4, p. 253-266Article in journal (Refereed)
    Abstract [en]

    Several orogenies have shaped the bedrock of southern Sweden. While mafic intrusions represent significant sources of information for reconstructing geodynamics and crustal evolution, the characterization of the various generations of such intrusions in Sweden remains limited. We reportin situzircon U-Pb ages and Hf isotope data from a Fe-Ti eclogite and a coronitic metagabbro from the Eastern Segment in southern Sweden. Crystallisation ages at 1683 +/- 17 Ma of the eclogite suggest affiliation with the surrounding 1730-1660 Ma Transscandinavian Igneous Belt intrusions that dominate the Eastern Segment. Secondary zircon growth and Pb-loss in the eclogite sample at 1459 +/- 44 Ma and the crystallisation of the metagabbro at 1431 +/- 26 Ma overlap and are related to magmatic activity during the Hallandian orogeny. Zircon Hf isotope signatures with chondritic and sub-chondritic values at similar to 1683 Ma and similar to 1431 Ma, respectively, correspond to an enriched (or mildly depleted) source in line with a "Mixed Svecofennian Crustal Reservoir". These isotope signatures are more enriched than those in the surrounding gneisses. Zircon isotope data from the herein analysed zircon grains indicate that the eclogite and metagabbro had an enriched mafic source in the mid to lower crust, or within the subcontinental lithospheric mantle below Fennoscandia.

  • 36.
    Rubinstein, Claudia V.
    et al.
    IANIGLA, CCT CONICET Mendoza, M5502IRA Mendoza, Argentina.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology.
    High diversity and early radiation of organic-walled phytoplankton in southern Baltica during the Middle-Late Ordovician – evidence from the Borenshult-1 drillcore of southern Sweden2023In: GFF, ISSN 1103-5897, E-ISSN 2000-0863Article in journal (Refereed)
    Abstract [en]

    Highly diverse and well preserved organic-walled phytoplankton were recorded from the Darriwilian–early Katian interval of the Borenshult-1 drillcore. We identified 154 species in 53 genera, and three assemblages were distinguished; Assemblage A of a late Darriwilian age, Assemblage B of a Sandbian age (further subdivided into sub-assemblages B1 and B2), and Assemblage C dated as Katian. Taxa with “Silurian affinities” with previous first appearance datum in the early Silurian, Hirnantian, such as Metaleiofusa and Visbysphaera, are here recorded from the late Darriwilian and Sandbian respectively. These occurrences question the relationship between the appearance of pioneering phytoplankton morphotypes and the Hirnantian glaciation. Other taxa with no pre-Silurian records such as Visbysphaera pirifera subsp. minor, Petaloferidium cazurrum and Dorsennidium cf. D. estrellitae are here present in the Sandbian, where bentonite beds are intercalated. The diversity curve of acritarchs shows similarities with those proposed for the Darriwilian-Katian of Baltica with main differences in the interval with bentonite beds representing an intense volcanic activity. The species Metaleiofusa arcuata Wall is here emended and a new combination is proposed: Petaloferidium cazurrum (Cramer) comb. nov. The genus Fankea is recorded for the first time from Swedish strata, suggesting a dominant high- to middle latitudinal distribution instead of a Perigondwanan distribution. We contend that the location of paleo-southern Sweden contributed to the great diversity seen, since a middle-low latitude provided a suitable habitat with warm, shallow water, rich in nutrients.

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    High diversity and early radiation of organic-walled phytoplankton in southern Baltica during the Middle-Late Ordovician – evidence from the Borenshult-1 drillcore of southern Sweden
  • 37.
    Rubinstein, Claudia
    et al.
    Department of Paleopalynology, IANIGLA, CCT CONICET Mendoza.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Baltica cradle of early land plants? Oldest record of trilete spores and diversecryptospore assemblages; evidence from Ordovician successions of Sweden2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 141, p. 181-190Article in journal (Refereed)
    Abstract [en]

    The origin of land plants is one of the most important evolutionary events in Earth’s history. The mode and timing of the terrestrialization of plants remains debated and previous data indicate Gondwana to be the center of land-plant radiation at ~ 470–460 Ma. Here we present the oldest occurrences of trilete spores, probably the earliest traces of vascular land plants yet recorded. The spores occur in Ordovician, Sandbian (455 million years old) successions in central Sweden, once part of the paleocontinent Baltica. These strata are independently dated by marine microfossils (conodonts) and 206Pb/238U dating of volcanic ash deposits. Our discovery extends the record of trilete spores globally by ~8 million years, and for Baltica by ~25 million years. Additionally, cryptospore assemblages are identified revealing a diverse and stable mid-Ordovician (Darriwilian: ~ 460 Ma) vegetation of free-sporing plants. The formation of regolith substrates on land as a consequence of permanent plant cover must in turn have affected the marine biota. We link these early land plant spore occurrences to the extensive, nutrient-rich volcanic ash deposits and propose Baltica as the possible original region of the radiation of early land plants.

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  • 38.
    Schwarzhans, Werner W.
    et al.
    Natural History Museum of Denmark, Copenhagen, Denmark, and Hamburg, Germany.
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Fish otoliths from the middle Paleocene (Selandian) of southern Sweden2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 277-282Article in journal (Refereed)
    Abstract [en]

    The first fossil otolith association from the middle Paleocene (Selandian) of Scania, southern Sweden is described. Forty-seven otoliths were retrieved from shallow wells representing 14 teleost taxa. Many specimens are small and/or eroded and, therefore, not identifiable to species level. Nevertheless, our findings indicate the potential for further fossil otolith discoveries in the region. The Scanian otolith-based fauna greatly resembles the better-known coeval association from Copenhagen, Denmark, but is relatively rich and diverse in perciform otoliths. The fauna records the first occurrence of Serranus? caribbaeus from the European Paleocene, and of Archaemacruroides ornatus from the Selandian of the North Sea Basin.

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  • 39. Shumlyanskyy, Leonid
    et al.
    Ernst, Richard
    Söderlund, Ulf
    Lund University.
    Billström, Kjell
    Swedish Museum of Natural History, Department of Geology.
    Mitrokhin, O
    Tsymbal, Stephan
    New U–Pb ages for mafic dykes in the Northwestern region of the Ukrainian shield: coeval tholeiitic and jotunitic magmatism2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 79-85Article in journal (Refereed)
    Abstract [en]

    The palaeoproterozoic Northwestern region of the Ukrainian shield hosts two compositional types of mafic dykes and associated magmatism that intruded at c. 1800–1760 Ma: (1) high-Ni dolerite dykes and layered intrusions of tholeiitic affinity and (2) high-Ti dolerite dykes of jotunitic affinity associated with anorthosite–mangerite–charnockite–granite (AMCG) suites. The jotunitic dykes represent initial melts for basic rocks of the Korosten AMCG plutonic complex, whereas tholeiitic dykes may reflect emplacement of a mantle plume and formation of a large igneous province (LIP). New U–Pb baddeleyite ages indicate that both compositional types can be coeval: the jotunitic Rudnya Bazarska dyke was emplaced at 1793 ・} 3 Ma, and the Zamyslovychi tholeiitic dolerite dyke at 1789 +/-9 Ma. In our model, the mantle plume-derived tholeiitic melts (underplate) supplied heat required for melting of the mafic lower crust and the production of jotunitic melts. As formation of the jotunite melts requires pressures in the range 10–13 kbar, either a thickened crust is needed or the lower crust must be subducted, or downthrusted, into the mantle. Alternatively, emplacement and ponding of large volume of tholeiitic melts might cause delamination of the lower crust, its sinking into the mantle, and further fusion to produce jotunitic melts.

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  • 40. Shumlyanskyy, Leonid
    et al.
    Mitrokhin, O
    Billström, Kjell
    Swedish Museum of Natural History, Department of Geology.
    Ernst, Richard
    Vishnevska, Eugenia
    Tsymbal, Stepan
    Cuney, Michel
    Soesoo, Alvar
    The ca. 1.8 Ga mantle plume related magmatism of the central part of the Ukrainian shield2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 86-101Article in journal (Refereed)
    Abstract [en]

    Palaeoproterozoic (ca. 1.8 Ga) mafic and ultramafic dykes are widely distributed within thewhole Sarmatian segment of the East-European craton. This paper focuses on new geochronological,geochemicaland isotope data obtained for mafic and ultramafic dykes of the Ingul terrain. Geochronological data available for these dykes indicate ages around 1800 Ma. We provide a new U–Pb zircon age of1810 ± 15 Ma obtained for a dolerite dyke in the Kirovograd area. Geochemical and petrographical dataallow identification of three groups of dykes: (1) kimberlites, (2) high-Mg# subalkaline rocks (picrite,camptonite, subalkaline dolerite etc.) and (3) tholeiite dolerite. Rocks of these groups were probably derived from different sources. Eps-Nd1800 values of studied rocks vary from 0.7 to 2.8. The highest values were obtained for mantle xenoliths and their kimberlite host (Eps-Nd1800 = 2.5–2.8). Rb–Sr data yield aregressionage of 1729 ± 20 Ma with an initial 87Sr/86Sr = 0.70366 ± 41 (MSWD = 10.8). The whole-rock lead isotope data scatter, but data for sub-groups of samples can tentatively be fitted to parallel 1.8 Ga isochrons.The geochemical data indicate rocks to have formed by partial melting and the degree of melting is thought to be a function of formation depth, the latter ranging from sub-lithospheric to lower crustal levels; we assume that melting was caused by a mantle plume. Dyking in the Ingul terrain was closely associated in time and space with metasomatic albitites that host numerous economic U deposits.

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  • 41. Shumlyanskyy, Leonid
    et al.
    Nosova, Anna
    Billström, Kjell
    Swedish Museum of Natural History, Department of Geology.
    Söderlund, Ulf
    Lund University.
    Andréasson, Per-Gunnar
    Lund University.
    Kuzmenkova, Oksana
    The U–Pb zircon and baddeleyite ages of the Neoproterozoic Volyn Large Igneous Province: implication for the age of the magmatism and the nature of a crustal contaminant2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 17-30Article in journal (Refereed)
    Abstract [en]

    The Volyn continental flood basalt province is situated on the western margin of the East European platform and constitutes a significant portion of the passive continental margin sequence formed along the Trans-European Suture Zone in response to Rodinia break-up in the Neoproterozoic. In Ukraine, the volcanogenic sequence is subdivided into suites called Zabolottya, Babyne and Ratne,which together with the lowermost terrigeneous Gorbashy suite comprise the Volyn series. Magmatic zircons from one high-Ti basalt sample yielded an age of 573 ± 14 Ma, whereas grains isolated from a rhyolitic dacite yielded an age of 571 ± 13 Ma. Baddeleyite from the olivine dolerite sample gave an older 206Pb/238U age of 626 ± 17 Ma, whereas the 207Pb/206Pb weighted average age of 567 ± 61 Ma is close to the zircon ages. Zircons separated from the other basaltic samples are much older and crystallized at c. 1290, 1470, 1820-1860, 1930-2050 and 2660 Ma. Ages in the 1820-1860 and 1930-2050 Ma time spans correspond to the ages of the Precambrian basement that underlies the Volyn province. However, the sources for the 1290, 1470 and 2660 Ma zircons are unknown, and these zircons must have been derivedfrom more distal areas.

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  • 42. Siliauskas, Laurynas
    et al.
    Skridlaite, Grazina
    Baginski, Bogusław
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Prusinskiene, Sabina
    What the ca. 1.83 Ga gedrite-cordierite schists in the crystalline basement of Lithuania tell us about the late Palaeoproterozoic accretion of the East European Craton2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 140, no 4, p. 332-344Article in journal (Refereed)
    Abstract [en]

    ABSTRACTIn the western East European Craton (EEC), southern Lithuania, a suite of fine-grained, thinly bedded rocks of unusual composition has been shown to have originally comprised intermediate and felsic volcanic rocks. They extruded at ca. 1.83 Ga and were hydrothermally altered prior to metamorphism, which converted them into garnet-, gedrite-, anthophyllite-, staurolite- and cordierite-bearing schists. After the rocks have experienced a 630°C and 7 kbar metamorphism, they were uplifted to 15 km (5 kbar) probably at ca. 1.73 Ga. They were reheated to 640°C at ca. 1.50 Ga (monazite age). The monazite age of ca. 1.50 Ga is coeval with the emplacement of the neighboring 1.50 Ga Anorthosite-Mangerite-Charnockite-Granite (AMCG) Mazury complex. The ca. 1.83 Ga volcanic suites in Lithuania and northern Poland, together with the Oskarshamn-Jönköping belt (OJB) in south-central Sweden, may belong to the same chain of volcanic island arcs, and thus provide information on the evolution of the entire western EEC. The ca. 1.50 Ga metamorphic reworking and the replacement of the Mazury AMCG suite may have been triggered by the Danopolonian orogeny further west and, at a larger scale, accretion of the continental margin of Columbia.

  • 43. Sjöqvist, Axel
    et al.
    Lindgren, Paula
    Sturkell, Erik
    Hogmalm, K
    Broman, Curt
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Lee, M
    Shock metamorphism and hydrothermal alteration of mafic impact ejecta from the Lockne impact structure, Sweden2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863Article in journal (Refereed)
  • 44.
    Skovsted, Christian
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Topper, Timothy, P.
    Swedish Museum of Natural History, Department of Paleobiology.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Johansson, Ove
    Swedish Museum of Natural History, Department of Paleobiology. Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
    Liu, Fan
    Swedish Museum of Natural History, Department of Paleobiology. Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden;State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life and Environments and Department of Geology, Northwest University, Xi’an, China.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    First discovery of Small Shelly Fossils and new occurrences of brachiopods and trilobites from the early Cambrian (Stage 4) of the Swedish Caledonides, Lapland2021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 134-150Article in journal (Refereed)
    Abstract [en]

    New fossil discoveries are reported from the Grammajukku Formation at Luobákte south of Lake Torneträsk in northern Swedish Lapland, including a fauna of Small Shelly Fossils (SSF) from a limestone bed in the uppermost part of the formation and new occurrences of brachiopods and trilobites in siltstones of the lower part of the formation. The moderately diverse SSF fauna is the first of its kind reported from the Swedish Caledonides and includes the first record of the tommotiid Lapworthella schodackensis and the bradoriid spine Mongolitubulus spinosus from Baltica, together with fragmentary specimens of Bradoria sp. and remains of one additional bradoriid arthropod, a protoconodont and a helcionelloid mollusc. In addition, the limestone bed yields abundant specimens of the brachiopods Botsfordia cf. caelata and Eoobolus cf. priscus and an unidentified ellipsocephalid trilobite. Lower down in the Grammajukku Formation, specimens of both brachiopod taxa, orthothecid hyoliths, the trilobite Ellipsocephalus cf. gripi and an unidentified holmiid trilobite were found at several levels in a siltstone, previously regarded as unfossiliferous. These discoveries markedly increase the known diversity of the palaeobiota from the Grammajukku Formation in northern Lapland and provide new insights into the biostratigraphy and palaeoenvironment of the lower Cambrian in Scandinavia and the palaeobiogeography of Cambrian faunas in general.

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  • 45.
    Skovsted, Christian
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Ushatinskaya, Galina
    Holmer, Lars, E.
    Popov, Leonid, E.
    Kouchinsky, Artem
    Swedish Museum of Natural History, Department of Paleobiology.
    Taxonomy, morphology, shell structure and early ontogeny of Pelmanotreta nom. nov. from the lower Cambrian of Siberia2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 1, p. 1-8Article in journal (Refereed)
    Abstract [en]

    The new generic name Pelmanotreta is proposed under the provisions of the International Code of Zoological Nomenclature (ICZN) to replace Cryptotreta Pelman, 1977 (Brachiopoda), a junior homonym of Cryptotreta Blanc & Foote, 1961 (Arthropoda). This poorly known brachiopod genus and its type and only species, Pelmanotreta neguertchenensis (Pelman, 1977), from the early Cambrian of Siberia is redescribed. The family-level taxonomy of Pelmanotreta and other “cryptotretid” brachiopods is uncertain. In Pelmanotreta, dorsal valves vastly outnumber ventral valves in all collections but new specimens of the poorly known ventral valve reveal a possibly septate and poorly mineralized apical region. A prismatic hexagonal shell structure comparable to that of Salanygolina is described. P. neguertchenensis preserves the earliest known record of a larval shell in brachiopods.

  • 46.
    Steinthorsdottir, Margret
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Bolin Centre for Climate Research, Stockholm University.
    Elliott-Kingston, Caroline
    School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland.
    Coiro, Mario
    Department of Biology, University of Fribourg, Fribourg, Switzerland.
    McElwain, Jennifer C.
    Botany Department, School of Natural Sciences, Trinity College Dublin, the University of Dublin, Dublin 2, Ireland.
    Searching for a nearest living equivalent for Bennettitales: a promising extinct plant group for stomatal proxy reconstructions of Mesozoic pCO22021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 190-201Article in journal (Refereed)
    Abstract [en]

    To understand Earth ́s climate variability and improve predictions of future climate change, studying past climates is an important avenue to explore. A previously published record of pCO2, across the Triassic–Jurassic boundary (TJB, ~201 Ma) of East Greenland, showed that Bennettitales (Anamozamites and Pterophyllum) responded in parallel to the empirically proven pCO2-responders Ginkgoales, reducing their stomatal densities by half across the TJB, indicating a transient doubling of pCO2. The abundance of fossil Bennettitales in Mesozoic strata and natural history museum collections worldwide offers enormous potential for further stomatal proxy pCO2 reconstructions, but a suitable nearest living equivalent (NLE) should ideally first be identified for this extinct plant group. Using specimens from herbarium collections, three species of cycads, historically considered the best NLE, were tested for pCO2 response, as well as two species of tree ferns, grown in experimental growth chambers. None responded to changes in pCO2, and were consequently rejected as NLEs. Finally, two species of ferns were selected from the literature, and produced very similar pCO2 compared to Ginkgoales. However, these understory ferns are not appropriate NLEs for Bennettitales due to differences in habitat and a distant evolutionary relationship. Future work should test additional plant groups, in particular seed plants such as basal angiosperms and Gnetales, for suitability as NLE for Bennettitales in pCO2 reconstructions, for example through biogeo- chemical fingerprinting using infrared microspectroscopy. Until an appropriate NLE is identified, Bennettitales pCO2 can be reconstructed based on cross-calibration of stomatal densities with those of co-occurring pCO2 responders, such as Ginkgoales.

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  • 47.
    Steinthorsdottir, Margret
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Elliott-Kingston, Caroline
    School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland.
    Coiro, Mario
    Department of Biology, University of Fribourg, Fribourg, Switzerland.
    McElwain, Jennifer C.
    Botany Department, School of Natural Sciences, Trinity College Dublin, the University of Dublin, Dublin 2, Ireland.
    Searching for a nearest living equivalent for Bennettitales: a promising extinct plant group for stomatal proxy reconstructions of Mesozoic pCO22021In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 143, no 2-3, p. 190-201Article in journal (Refereed)
    Abstract [en]

    To understand Earth ́s climate variability and improve predictions of future climate change, studying past climates is an important avenue to explore. A previously published record of pCO2, across the Triassic– Jurassic boundary (TJB, ~201 Ma) of East Greenland, showed that Bennettitales (Anamozamites and Pterophyllum) responded in parallel to the empirically proven pCO2-responders Ginkgoales, reducing their stomatal densities by half across the TJB, indicating a transient doubling of pCO2. The abundance of fossil Bennettitales in Mesozoic strata and natural history museum collections worldwide offers enormous potential for further stomatal proxy pCO2 reconstructions, but a suitable nearest living equivalent (NLE) should ideally first be identified for this extinct plant group. Using specimens from herbarium collections, three species of cycads, historically considered the best NLE, were tested for pCO2 response, as well as two species of tree ferns, grown in experimental growth chambers. None responded to changes in pCO2, and were consequently rejected as NLEs. Finally, two species of ferns were selected from the literature, and produced very similar pCO2 compared to Ginkgoales. However, these understory ferns are not appropriate NLEs for Bennettitales due to differences in habitat and a distant evolutionary relationship. Future work should test additional plant groups, in particular seed plants such as basal angiosperms and Gnetales, for suitability as NLE for Bennettitales in pCO2 reconstructions, for example through biogeo- chemical fingerprinting using infrared microspectroscopy. Until an appropriate NLE is identified, Bennettitales pCO2 can be reconstructed based on cross-calibration of stomatal densities with those of co-occurring pCO2 responders, such as Ginkgoales.

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  • 48.
    Steinthorsdottir, Margret
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Bolin Centre for Climate Research, Stockholm University.
    Friederike, Wagner-Cremer
    Hot summers ahead? Multi-decadal spring season warming precedes sudden summer temperature rise in pre-anthropogenic climate change.2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, p. 175-180Article in journal (Refereed)
    Abstract [en]

    Waning annual seasonality is documented in an up to one-month advance in spring onset since the 1980’s in northern latitudes, perturbing ecosystems and socio-economic performance. Summer temperatures, in contrast, have been rising only recently, indicating an offset in seasonal warming. The limited time span of this observational data makes the asynchronous pattern difficult to quantify, hindering projections of intra-annual dynamics. We explore temporal phase relations of seasonal warming over the Late Pleniglacial/Bølling and the Younger Dryas/Holocene climate transitions that preceded present anthropogenic warming. We determine past spring onset and thermal properties from dwarf birch paleo-phenology. Reconstructed spring warming led maximum summer warming by about a century during both transitions. Long-term reconstruction of intra-annual temperature regimes provides the perspective required for seasonal response analysis. Our results document that multidecadal spring season warming precedes sudden summer temperature rise also during natural climate change. The rapidity of present seasonality changes, however, is unprecedented.

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  • 49.
    Topper, Timothy P.
    et al.
    Geologisk Museum, Statens Naturhistoriske Museum, Danmark.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    A new name for a classic Cambrian Swedish brachiopod, Tallatella undosa (Moberg)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 3, p. 429-435Article in journal (Refereed)
    Abstract [en]

    The brachiopod originally described as Kuturgina undosa Moberg, 1892 from the early Cambrian (Cambrian Series 2, Stage 4) När Shale of Kalmarsund, Sweden, has experienced a long and turbulent history since the original description over 100 years ago. Uncertainties regarding key morphological characters have resulted in the species taxonomically hopping between genera until it wasrecently assigned to the poorly known genus Cryptotreta Pelman, 1977 and subsequently transferred to the problematic paterinate family Cryptotretidae. Despite members of this group representing the oldest brachiopods in the fossil record, they remain enigmatic, both taxonomically and phylogenetically. Theidentification of the brachiopod species from the När Shale as a cryptotretid means that this brachiopod was the first member of the family to be discovered, yet its systematic position is far from certain. Examination of type material in addition to supplementary material acquired from the Skäggenäs Peninsula, Sweden, has elucidated many of the previous ambiguous morphological characteristics of the species. The new morphological information acquired here has resulted in the erection of a new paterinate genus, Tallatella gen. nov., to accommodate the Swedish material previously described as Cryptotreta undosa.

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    Topper and Skovsted 2014 - Tallatella manuscript
  • 50. Topper, Timothy
    et al.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    A new name for a classic Cambrian Swedish brachiopod, Tallatella undosa (Moberg)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 4, p. 429-435Article in journal (Refereed)
    Abstract [en]

    The brachiopod originally described as Kuturgina undosa Moberg, 1892 from the early Cambrian (Cambrian Series 2, Stage 4) Nar Shale of Kalmarsund, Sweden, has experienced a long and turbulent history since the original description over 100 years ago. Uncertainties regarding key morphological characters have resulted in the species taxonomically hopping between genera until it was recently assigned to the poorly known genus Cryptotreta Pelman, 1977 and subsequently transferred to the problematic paterinate family Cryptotretidae. Despite members of this group representing the oldest brachiopods in the fossil record, they remain enigmatic, both taxonomically and phylogenetically. The identification of the brachiopod species from the Nar Shale as a cryptotretid means that this brachiopod was the first member of the family to be discovered, yet its systematic position is far from certain. Examination of type material in addition to supplementary material acquired from the Skaggenas Peninsula, Sweden, has elucidated many of the previous ambiguous morphological characteristics of the species. The new morphological information acquired here has resulted in the erection of a new paterinate genus, Tallatella gen. nov., to accommodate the Swedish material previously described as Cryptotreta undosa.

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