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  • 1.
    Bomfleur, Benjamin
    et al.
    Westfälische Wilhelms-Universität, Münster, Germany.
    Blomenkemper, Patrick
    Westfälische Wilhelms-Universität, Münster, Germany.
    Kerp, Hans
    Westfälische Wilhelms-Universität, Münster, Germany.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Polar regions of the Mesozoic–Paleogene greenhouse world as refugia for relict plant groups2018Ingår i: Transformative Paleobotany: Papers to Commemorate the Life and Legacy of Thomas N. Taylor / [ed] Krings, M., Harper, C.J., Cúneo, N.R., Rothwell, G.W., Amsterdam: Elsevier, 2018, s. 593-611Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Throughout Earth history, plants were apparently less dramatically affected by global biotic crises than animals. Here, we present the unexpected occurrence of Dicroidium, the iconic plant fossil of the Gondwanan Triassic, in Jurassic strata of East Antarctica. The material consists of dispersed cuticles of three Dicroidium species, including the type species D. odontopteroides. These youngest occurrences complement a remarkable biogeographic pattern in the distribution of Dicroidium through time: the earliest records are from palaeoequatorial regions, whereas the last records are from polar latitudes. We summarize similar, relictual high-latitude occurrences in other plant groups, including lycopsids, various ‘seed ferns’, Bennettitales, and cheirolepid conifers, to highlight a common phenomenon: during times of global warmth, the ice-free high-latitude regions acted as refugia for relictual plant taxa that have long disappeared elsewhere. Eventually, such last surviving polar populations probably disappeared as they became outcompeted by newly emerging plant groups in the face of environmental change.

  • 2.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Decombeix, Anne-Laure
    Schwendemann, Andrew
    Escapa, Ignacio
    Taylor, Edith
    Taylor, Thomas
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Habit and Ecology of the Petriellales, an Unusual Group of Seed Plants from the Triassic of Gondwana2014Ingår i: International journal of plant sciences, ISSN 1058-5893, E-ISSN 1537-5315, Vol. 175, nr 9, s. 1062-1075Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Premise of research. Well-preserved Triassic plant fossils from Antarctica yield insights into the physiology of plant growth under the seasonal light regimes of warm polar forests, a type of ecosystem without any modern analogue. Among the many well-known Triassic plants from Antarctica is the enigmatic Petriellaea triangulata, a dispersed seedpod structure that is considered a possible homologue of the angiosperm carpel. However, the morphology and physiology of the plants that produced these seedpods have so far remained largely elusive.

    Methodology. Here, we describe petriellalean stems and leaves in compression and anatomical preservation that enable a detailed interpretation of the physiology and ecology of these plants.

    Pivotal results. Our results indicate that the Petriellales were diminutive, evergreen, shade-adapted perennial shrubs that colonized the understory of the deciduous forest biome of polar Gondwana. This life form is very unlike that of any other known seed-plant group of that time. By contrast, it fits remarkably well into the “dark and disturbed” niche that some authors considered to have sheltered the rise of the flowering plants some 100 Myr later.

    Conclusions. The hitherto enigmatic Petriellales are now among the most comprehensively reconstructed groups of extinct seed plants and emerge as promising candidates for elucidating the mysterious origin of the angiosperms.

  • 3.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Grimm, Guido
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Osmunda pulchella sp. nov. from the Jurassic of Sweden--reconciling molecular and fossil evidence in the phylogeny of modern royal ferns (Osmundaceae)2015Ingår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 15, nr 126, s. 1-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The classification of royal ferns (Osmundaceae) has long remained controversial. Recent molecular phylogenies indicate that Osmunda is paraphyletic and needs to be separated into Osmundastrum and Osmunda s.str. Here, however, we describe an exquisitely preserved Jurassic Osmunda rhizome (O. pulchella sp. nov.) that combines diagnostic features of both Osmundastrum and Osmunda, calling molecular evidence for paraphyly into question. We assembled a new morphological matrix based on rhizome anatomy, and used network analyses to establish phylogenetic relationships between fossil and extant members of modern Osmundaceae. We re-analysed the original molecular data to evaluate root-placement support. Finally, we integrated morphological and molecular data-sets using the evolutionary placement algorithm.

    Results: Osmunda pulchella and five additional Jurassic rhizome species show anatomical character suites intermediate between Osmundastrum and Osmunda. Molecular evidence for paraphyly is ambiguous: a previously unrecognized signal from spacer sequences favours an alternative root placement that would resolve Osmunda s.l. as monophyletic. Our evolutionary placement analysis identifies fossil species as probable ancestral members of modern genera and subgenera, which accords with recent evidence from Bayesian dating.

    Conclusions: Osmunda pulchella is likely a precursor of the Osmundastrum lineage. The recently proposed root placement in Osmundaceae—based solely on molecular data—stems from possibly misinformative outgroup signals in rbcL and atpA genes. We conclude that the seemingly conflicting evidence from morphological, anatomical, molecular, and palaeontological data can instead be elegantly reconciled under the assumption that Osmunda is indeed monophyletic.

  • 4.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Westfälische Wilhelms-Universität Münster.
    Grimm, Guido
    Department fu¨r Pala¨ontologie, Universita¨t Wien, Wien, Austria.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes2017Ingår i: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 5, artikel-id e3433Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema, Donwelliacaulis, and Tiania; (2) the thamnopteroid genera Zalesskya, Iegosigopteris, and Petcheropteris are all considered synonymous with Thamnopteris; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis. In addition, we consider Millerocaulis stipabonettiorum a possible member of Palaeosmunda and Millerocaulis estipularis as probably constituting the earliest representative of the (Todea-)Leptopteris lineage (subtribe Todeinae) of modern Osmundoideae.

  • 5.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Klymiuk, Ashley
    Taylor, Edith
    Taylor, Thomas
    Gulbranson, Erik
    Isbell, John
    Diverse bryophyte mesofossils from the Triassic of Antarctica2014Ingår i: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 47, nr 1, s. 120-132Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Compared with the fossil record of vascular plants, bryophyte fossils are rare; this circumstance is probably related to a lower preservation potential compared with that of vascular plants. We searched for bryophyte remains in extensive collections of plant-fossil assemblages from the Triassic of Antarctica and identified three assemblages with surprisingly well-preserved bryophyte fossils. Although most bryophyte remains are too fragmented to conclusively place them in a detailed systematic context, they exhibit features sufficient to suggest the presence of at least four types of leafy bryophytes and two orders of thallose liverworts (Pallaviciniales and Metzgeriales) in the high-latitude Triassic ecosystems of Antarctica. The leafy bryophytes exhibit combinations of morphological features (e.g. keeled and entire-margined, ecostate leaves with elongated cells) that today occur in only a few small, systematically isolated groups, but were common among Palaeozoic and especially Mesozoic bryophytes. The diverse morphologies of the bryophyte fossils add further support to previous hypotheses that during warmer periods in the Earth’s history, bryophyte vegetation may have been particularly rich and diverse in high-latitude regions. Through analysis of the sedimentology and taphonomy of these assemblages, we identify a combination of key factors that may explain the preservation of bryophyte fossils in these deposits: (1) punctuated, high-energetic sedimentary events causing traumatic removal and incorporation of bryophytes into sediment-laden flood waters; (2) limited transport distance, and short period of suspension, followed by rapid settling and burial as a result of a rapidly decelerating flow discharging into a floodplain environment; and (3) early-diagenetic cementation with iron hydroxides in locally anoxic zones of the organic-rich, muddy substrate.

  • 6.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Vajda, Vivi
    Lund University.
    Fossilized nuclei and chromosomes reveal 180 millionyears of genomic stasis in Royal Ferns2014Ingår i: Science, ISSN ISSN 0036-8075, Vol. 343, s. 1376-1377Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rapidly permineralized fossils can provide exceptional insights into the evolution of life over geological time. Here, we present an exquisitely preserved, calcified stem of a royal fern (Osmundaceae) from Early Jurassic lahar deposits of Sweden in which authigenic mineral precipitation from hydrothermal brines occurred so rapidly that it preserved cytoplasm, cytosol granules, nuclei, and even chromosomes in various stages of cell division. Morphometric parameters of interphase nuclei match those of extant Osmundaceae, indicating that the genome size of these reputed “living fossils” has remained unchanged over at least 180 million years—a paramount example of evolutionary stasis.

  • 7.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Mörs, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Ferraguti, Marco
    Dipartimento di Bioscienze, Universita` degli Studi di Milano, Milano, Italy.
    Reguero, Marcelo
    Divisio´n Paleontologı´a de Vertebrados, Museo de La Plata, La Plata, Argentina.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Fossilized spermatozoa preserved in a 50-myr-old annelid cocoon from Antarctica2015Ingår i: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, nr 20150431, s. 1-5Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The origin and evolution of clitellate annelids—earthworms, leeches and their relatives—is poorly understood, partly because body fossils of these delicate organisms are exceedingly rare. The distinctive egg cases (cocoons) of Clitellata, however, are relatively common in the fossil record, although their potential for phylogenetic studies has remained largely unexplored. Here, we report the remarkable discovery of fossilized spermatozoa preserved within the secreted wall layers of a 50-Myr-old clitellate cocoon from Antarctica, representing the oldest fossil animal sperm yet known. Sperm characters are highly informative for the classification of extant Annelida. The Antarctic fossil spermatozoa have several features that point to affinities with the peculiar, leech-like ‘crayfish worms’ (Branchiobdellida). We anticipate that systematic surveys of cocoon fossils coupled with advances in non-destructive analytical methods may open a new window into the evolution of minute, soft-bodied life forms that are otherwise only rarely observed in the fossil record.

  • 8.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Schöner, Robert
    John, Nadine
    Schneider, Jörg
    Elsner, Martin
    Viereck-Goette, Lothar
    Kerp, Hans
    New Palaeozoic deposits of the Victoria Group in the Eisenhower Range, northern Victoria Land, Antarctica2014Ingår i: Antarctic Science, ISSN 0954-1020, E-ISSN 1365-2079, Vol. 26, nr 3, s. 277-278Artikel i tidskrift (Refereegranskat)
  • 9.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Schöner, Robert
    Schneider, Jörg
    Viereck, Lothar
    Kerp, Hans
    McKellar, John
    From the Transantarctic Basin to the Ferrar Large Igneous Province: New palynostratigraphic age constraints for Triassic-Jurassic sedimentation and magmatism in East Antarctica2014Ingår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 207, s. 18-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present new palynological data from the Transantarctic Mountains that clarify the timing of sedimentary and magmatic processes in the transition from continental deposition of the Beacon Supergroup to emplacement of the Ferrar Large Igneous Province. Samples were collected from twenty-three Triassic and Jurassic sections in the southern area of north Victoria Land (NVL), East Antarctica. Recovered palynomorph assemblages are correlated with the widely used, although informal palynostratigraphic framework established for eastern Australia by Price. The associated Late Triassic–earliest Jurassic zone, APT5, is modified here with a proposed new subdivision: Lower APT5 (“APT5L”; middle–late Norian), Middle APT5 (“APT5M”; Rhaetian), and Upper APT5 (“APT5U”;Hettangian–earliest Sinemurian). We further propose a modification unifying the relevant formal eastern Australian and New Zealand palynostratigraphic zones, with a new Polycingulatisporites crenulatus Association Zone (new zonal status) that includes the P. crenulatus Association Subzone (new subzone; equivalent toAPT5L) and the following Foveosporites moretonensis Association Subzone (new subzonal status; equivalent to APT5M). Our palynostratigraphic dating of the NVL assemblages demonstrates that the onset of sedimentation was diachronous in this part of the Transantarctic Basin, ranging from at least the Rhaetian to, in places, early Sinemurian. By lack of evidence for rocks containing APT5U assemblages and by analogy with the few coeval sections in Australia, we infer that the Hettangian interval in NVL is probably consumed by unconformity. Depositionof ashes from distal silicic volcanism commenced in the early Sinemurian and reached a peak phase beginning in middle Pliensbachian (ca 187Ma), coinciding with the first major magmatic interval of the silicic Chon Aike Province in Patagonia and West Antarctica. Two major episodes of phreatomagmatic activity, driven by shallow-level sill intrusion into sandstone aquifers, occurred during the middle Pliensbachian and during the late Pliensbachian–early Toarcian. The latter episode was closely followed by the first pillow extrusion and local lava effusion. Contrary to some previous studies, we further conclude that all available palynological evidence is compatible with a short-lived emplacement of the plateau-forming Kirkpatrick Basalt at around 180 Ma during the early Toarcian.

  • 10.
    Choo, Thereis
    et al.
    School of Integrative Plant Science, Cornell University, Ithaca,.
    Escapa, Ignacio
    CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Chubut, Argentina.
    Benjamin, Bomfleur
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Monotypic colonies of Clathropteris meniscioides (Dipteridaceae) from the Early Jurassic of central Patagonia, Argentina: implications for taxonomy and palaeoecology2016Ingår i: Palaeontographica. Abteilung B, Palaophytologie, ISSN 0375-0299, Vol. 294, s. 85-109Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A collection of over 130 specimens of the fossil dipterid fern Clathropteris meniscioides (Brongn. 1825) Brongn. 1828 from in-situ colonies in the Lower Jurassic of Chubut, Argentina, provides evidence for population-level morphological variation within the species and palaeoecology of the site. Characters such as angle of insertion of secondary veins, tertiary vein arrangement and tooth depth were observed to vary between specimens, and the total range of variation captured by this population was found to overlap and intergrade with the descriptions of several previously identified Clathropteris species. This suggests that species delimitations based on minor differences in such characters should be regarded with skepticism, and that the current number of species ascribed to this genus may be artificially inflated. Abundant C. meniscioides fossils at different development stages buried together in a single, thick bed of sheet-flood deposits provide evidence for the species having formed large, pure colonies in open, disturbed floodplain areas. The characteristic and extremely high leaf-vein densities would have allowed for greater carbon assimilation and rapid growth rates. Altogether, this suggests that the species was a fast-growing pioneer species of floodplains, a prominent part of the Early Jurassic vegetation in Gondwana, and a likely food source for large herbivorous dinosaurs common at that time.

  • 11. Decombeix, Anne-Laure
    et al.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Taylor, Edith
    Taylor, Thomas
    New data on the anatomy and systematic affinities of corystosperm wood from the Triassic of Antarctica2014Ingår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 203, nr 1, s. 22-34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Anatomically preserved trunks and young stems of corystosperm seed ferns are described from the Triassic of Fremouw Peak, Beardmore Glacier area, Antarctica. Based on characters of the primary and secondary vascular system, these new specimens are assigned to Kykloxylon, a genus that was established based on young stems with attached Dicroidium leaf bases. The largest specimens illustrate how some secondary growth characters, such as unequal cambial activity, appeared during later development, which enables a better comparison of Kykloxylon with trunks assigned to other corystosperm genera. Jeffersonioxylon from the Gordon Valley, Antarctica, and Cuneumxylon from South America show strong similarities with the newly described larger Kykloxylon trunks from Fremouw Peak, and might be considered congeneric. Our results provide further support for the presence of two anatomically and morphologically distinct kinds of Dicroidium-bearing trees in the Triassic vegetation of Gondwana, one with a palm-like habit and Rhexoxylon stems and the other with a more Ginkgo-like habit and Kykloxylon/Cuneumxylon-type stems

  • 12.
    Elgorriaga, Andrés
    et al.
    Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón nº 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina.
    Escapa, Ignacio
    Consejo Nacional de Investigaciones Científicas y Técnicas, Museo Paleontológico Egidio Feruglio, Avenida Fontana 140, U9100GYO Chubut, Argentina.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Cúneo, Rubén
    Consejo Nacional de Investigaciones Científicas y Técnicas, Museo Paleontológico Egidio Feruglio, Avenida Fontana 140, U9100GYO Chubut, Argentina.
    Ottone, Eduardo
    Instituto de Estudios Andinos Don Pablo Groeber-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón n° 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina.
    Reconstruction and phylogenetic significance of a new Equisetum Linnaeus species from the Lower Jurassic of Cerro Bayo (Chubut province, Argentina)2015Ingår i: Ameghiniana, ISSN 1851-8044, Vol. 52, s. 135-152Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe Equisetum dimorphum sp. nov. from the Lower Jurassic of Chubut Province, Patagonia, Argentina. This new species is based on fertile and vegetative remains preserved as impressions of stems, leaves, strobili, transversal sections of the stems showing their anatomy, and terminal pagoda-like structures. The fine-grained sedimentary matrix also preserved detailed impressions of epidermal features. The morphological characters allow a whole-plant reconstruction and assignment to Equisetum. Equisetum dimorphum sp. nov. shows a mosaic of morphological characters that are commonly present in other Mesozoic forms and representatives of the two extant Equisetum subgenera, e.g., sunken stomata and a blunt strobilus apex. Compared to other well-known Mesozoic equisetalean taxa, Equisetum dimorphum sp. nov. appears to be most closely related to a group of Jurassic Equisetum-like plants including Equisetum laterale Phillips and Equisetites ferganensis Seward. Additional evidence for the morphological stasis of the fertile and vegetative organs of extant horsetails is supplied with this new material, adding further support to the hypothesis that the extant horsetails are a successful group that has undergone only little morphological changeover time and that has been present, nearly worldwide, since Jurassic times.

  • 13.
    Grimm, Guido
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Kapli, Paschalia
    3Natural History Museum of Crete and Biology Department, University of Crete, PO Box 2208, 71409 Heraklion, Crete, Greece.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Renner, Susanne
    Using more than the oldest fossils: Dating Osmundaceae with three Bayesian clock approaches2015Ingår i: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 64, nr 3, s. 396-405Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A major concern in molecular clock dating is how to use information from the fossil record to calibrate genetic distances from DNA sequences. Here we apply three Bayesian dating methods that differ in how calibration is achieved—“node dating” (ND) inBEAST, “total evidence” (TE) dating in MrBayes, and the “fossilized birth–death” (FBD) in FDPPDiv—to infer divergence times in the royal ferns. Osmundaceae have 16–17 species in four genera, two mainly in the Northern Hemisphere and two in South Africa and Australasia; they are the sister clade to the remaining leptosporangiate ferns. Their fossil record consists of at least 150 species in ∼17 genera. For ND, we used the five oldest fossils, whereas for TE and FBD dating, which do not require forcing fossils to nodes and thus can use more fossils,we included up to 36 rhizomes and frond compression/impression fossils, which for TE datingwere scored for 33morphological characters.We also subsampled 10%, 25%, and 50% of the 36 fossils to assess model sensitivity. FBD-derived divergence ages were generally greater than those inferred from ND; two of seven TE-derived ages agreed with FBD-obtained ages, the others were much younger or much older than ND or FBD ages. We prefer the FBD-derived ages because they best fit the Osmundales fossil record (including Triassic fossils not used in our study). Under the preferred model, the clade encompassing extant Osmundaceae (and many fossils) dates to the latest Paleozoic to Early Triassic; divergences of the extant species occurred during the Neogene. Under the assumption of constant speciation and extinction rates, the FBD approach yielded speciation and extinction rates that overlapped those obtained from just neontological data. However, FBD estimates of speciation and extinction are sensitive to violations in the assumption of continuous fossil sampling; therefore, these estimates should be treated with caution.

  • 14. Hübers, M
    et al.
    Bomfleur, B
    Krings, M
    Pott, C
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Kerp, H
    A reappraisal of Mississippian (Tournaisian and Visean) adpression floras from central and northwestern Europe2014Ingår i: Zitteliana, Series A, ISSN 1612-412X, Vol. 54, s. 39-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mississippian plant fossils are generally rare, and in central and northwestern Europe especially Tournaisian to middle Visean fossil floras are restricted to isolated occurrences. While sphenophytes and lycophytes generally are represented by only a few widespread and long-ranging taxa such as Archaeocalamites radiatus, Sphenophyllum tenerrimum and several species of Lepidodendropsis and Lepidodendron, Visean floras in particular show a remarkably high diversity of fern-like foliage, including filiform types (Rhodea, Diplotmema), forms with bipartite fronds (Sphenopteridium, Diplopteridium, Spathulopteris, Archaeopteridium), others with monopodial, pinnate fronds (Anisopteris, Fryopsis) and still others characterized by several-times pinnate fronds (e.g., Adiantites, Triphyllopteris, Sphenopteris, Neuropteris). Most of these leaf types have been interpreted as belonging to early seed ferns, whereas true ferns seem to have been rare or lacking in impression/compression floras. In the upper Visean, two types of plant assemblages can be distinguished, i.e., the northern Kohlenkalk-type and the south-eastern Kulm-type assemblage. Although several compression/impression taxa have been revised in recent years to provide a more uniform classification, additional parameters such as different modes of preservation and imprecise information on stratigraphic age hamper detailed interregional comparisons of Mississippian floras.

  • 15.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bomfleur, Benjamin
    Westfälische Wilhelms-Universität, Münster, Germany.
    Drinnan, Andrew N.
    School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia.
    Pachytestopsis tayloriorum gen. et sp. nov., an anatomically preserved glossopterid seed from the Lopingian of Queensland, Australia2018Ingår i: Transformative Paleobotany: Papers to Commemorate the Life and Legacy of Thomas N. Taylor / [ed] Krings, M., Harper, C.J., Cúneo, N.R., Rothwell, G.W., Amsterdam: Elsevier, 2018, s. 155-178Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    A permineralized seed, Pachytestopsistayloriorum gen. et sp. nov., is described from the Changhsingian (upper Permian) Fort Cooper Coal Measures at the Homevale locality in the northern Bowen Basin, Queensland,Australia. This largest permineralized seed species yet recorded from Permian deposits of Gondwana conforms to a size accommodated by either Rigbyaceae or Lidgettoniaceae (glossopterid) fructifications recorded elsewhere in the Sydney-Bowen basin complex. The seeds are characterized by a thin endotesta of longitudinally orientated cells, thick mesotesta incorporating an inner band of very thick walled sclereids and an outer layer of thin-walled parenchymatous cells, and an exotesta that comprises a well-developed epidermis and several layers of thick-walled hypodermal cells. Vascular supply to the base of the seed passes through the integument and bifurcates into the nucellar pad. Taeniate bisaccate pollen of Protohaploxypinus-type occurs in the pollen chamber of the seed. A comparison of the characters of P. tayloriorum with other permineralized seeds from the Permian of Gondwana indicates that several of the characters used in previous phylogenetic analyses incorporating glossopterids are wrongly scored or ambiguous in their definition.

  • 16.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Mörs, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Reguero, Marcelo
    División Paleontología de Vertebrados, Museo de La Plata, Paseo del Bosque s/n, B1900FWA La Plata, Argentina.
    Fossil clitellate annelid cocoons and their microbiological inclusions from the Eocene of Seymour Island, Antarctica2016Ingår i: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 19, nr 1.11A, s. 1-27Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Clitellate annelids have a meagre body fossil record but they secrete proteinaceous

    cocoons for the protection of eggs that, after hardening, are readily fossilized

    and offer a largely untapped resource for assessing the evolutionary history of this

    group. We describe three species of clitellate cocoons (viz., Burejospermum seymourense

    sp. nov., B. punctatum sp. nov. and Pegmatothylakos manumii gen. et sp. nov.)

    from the lower Eocene La Meseta Formation, Seymour Island, Antarctica. The

    cocoons probably derive from continental settings and were transported to, and preserved

    within, nearshore marine to estuarine environments. The cocoons provide the

    first evidence of commensal or parasitic relationships in the Eocene continental ecosystems

    of Antarctica. Moreover, numerous micro-organisms and the oldest fossilized

    examples of animal spermatozoa are preserved as moulds within the consolidated

    walls of the cocoons. Fossil annelid cocoons offer potential for enhanced palaeoenvironmental

    interpretation of sediments, correlation between continental and shallowmarine

    strata, and improved understanding of the development of clitellate annelid

    reproductive traits and the evolutionary history of soft-bodied micro-organisms in general.

  • 17.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Vajda, Vivi
    Lund University.
    A phenomenal fossil fern, forgotten for forty years2014Ingår i: Deposits Magazine, ISSN 17749588, Vol. 40, s. 16-21Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    On some occasions, it is the hard sweat and toil of palaeontologists labouring in the field at carefully planned excavation sites that yields the prize specimen on which careers are built. On other occasions, it is the chance discovery by an amateur collector that may yield that special fossil. We present an account of one such remarkable fossil discovery by an eccentric farmer in southern Sweden. However, more remarkable is that this exceptional fossil remained unstudied and largely unnoticed in a major museum for almost 40 years, before its true significance was realised.

  • 18.
    Pott, Christian
    et al.
    LWL-Museum of Natural History, Münster, Germany.
    Bouchal, Johannes M.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Choo, Thereis Y.S.
    Yousif, Rihab
    Bomfleur, Benjamin
    Westfälische Wilhelms-Universität, Münster, Germany.
    Ferns and fern allies from the Carnian (Upper Triassic) of Lunz am See, Lower Austria: A melting pot of Mesozoic fern vegetation2018Ingår i: Palaeontographica. Abteilung B, Palaophytologie, ISSN 0375-0299, Vol. 297, nr 1–6, s. 1-101Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The floral assemblage from the Carnian (Upper Triassic) of Lunz-am-See in Austria contains a rich and diverse array of ferns and fern allies, most of which have been considered only marginally, some have been described but more than a century ago and the majority have never been illustrated. Therefore, we here provide a detailed analysis of these taxa accompanied by extensive descriptions, detailed illustrations and colour restorations of the plants. We identified 17 species of lycophytes, sphenophytes and pteridophytes assignable to 14 genera in seven families. One taxon could be identified to class level only. One new genus of dipteridacean ferns (viz. Digitopteris C.Pott et Bomfleur gen. nov.), so far monotypic, is here described from Lunz with its type species Digitopteris repanda C.Pott et Bomfleur sp. nov. The Lunz flora comprises an interesting mixture of eusporangiate Marattiales and leptosporangiate Osmundales, Gleicheniales and Schizaeales; the former representing a rather primitive group of ferns. The co-occurrence of eusporangiate and leptosporangiate ferns renders the Lunz flora important given the fact that eusporangiate ferns were predominating over more modern, leptosporangiate forms during the Paleozoic, whereas they typically constitute only subordinate components in fern vegetation since the mid-Mesozoic until today. Among the leptosporangiate forms, the species from Lunz represent, due to their Triassic age, more primitive forms, which probably were rather growth-restricted thriving as herbaceous understorey layer among the shade of the eusporangiate, tree-like marattialean ferns.

  • 19.
    Schneebeli-Hermann, Elke
    et al.
    Palaeoecology, Institute of Environmental Biology, Faculty of Science, Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands.
    Kürschner, Wolfram
    Department of Geosciences, University of Oslo, P.O. Box 1047, Blindern, N-0316 Oslo, Norway.
    Kerp, Hans
    Forschungsstelle für Paläobotanik am Institut für Geologie und Paläontologie, Westfälische Wilhelms-Universität Münster, Hindenburgplatz 57, 48143 Münster, Germany.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hochuli, Peter
    Institute and Museum of Palaeontology, University of Zurich, Karl Schmid-Str. 4, CH-8006 Zurich, Switzerland.
    Bucher, Hugo
    Institute and Museum of Palaeontology, University of Zurich, Karl Schmid-Str. 4, CH-8006 Zurich, Switzerland.
    Ware, David
    Institute and Museum of Palaeontology, University of Zurich, Karl Schmid-Str. 4, CH-8006 Zurich, Switzerland.
    Roohi, Ghazala
    Pakistan Museum of Natural History, Garden Avenue, Islamabad 44000, Pakistan.
    Vegetation history across the Permian–Triassic boundary in Pakistan (Amb section, Salt Range)2015Ingår i: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 27, s. 911-924Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hypotheses about the Permian–Triassic floral turnover range from a catastrophic extinction of terrestrial plant communities to a gradual change in floral composition punctuated by intervals indicating dramatic changes in the plant communities. The shallow marine Permian–Triassic succession in the Amb Valley, Salt Range, Pakistan, yields palynological suites together with well-preserved cuticle fragments in a stratigraphically well-constrained succession across the Permian–Triassic boundary. Palynology and cuticle analysis indicate a mixed GlossopterisDicroidium flora in the Late Permian. For the first time Dicroidium cuticles are documented from age-constrained Upper Permian deposits on the Indian subcontinent. Close to the Permian–Triassic boundary, several sporomorph taxa disappear. However, more than half of these taxa reappear in the overlying Smithian to Spathian succession. The major floral change occurs towards the Dienerian. From the Permian–Triassic boundary up to the middle Dienerian a gradual increase of lycopod spore abundance and a decrease in pteridosperms and conifers are evident. Synchronously, the generic richness of sporomorphs decreases. The middle Dienerian assemblages resemble the previously described spore spikes observed at the end-Permian (Norway) and in the middle Smithian (Pakistan) and might reflect a similar ecological crisis.

  • 20.
    Vajda, Vivi
    et al.
    Lund University.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Fossilfyndet i Korsaröd2014Ingår i: Geologiskt Forum, ISSN 1104-4721, Vol. 82, s. 24-29Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [sv]

    Upptackten av ett extremt valbevarat ormbunksfossil, inkapslat i laharflodena vid Korsarod och Djupadalsmollan, vacker nu hopp hos forskarna om att hitta fler fynd. Dessutom ska ormbunken testas for fossilt DNA.

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