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  • 1. Qu, Yuangao
    et al.
    Zhu, Shixing
    Whitehouse, Martin J.
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Engdahl, Anders
    McLoughlin, Nicola
    Carbonaceous biosignatures of the earliest putative macroscopic multicellular eukaryotes from 1630 Ma Tuanshanzi Formation, north China2018Ingår i: Precambrian Research, ISSN 0301-9268, E-ISSN 1872-7433, Vol. 304, s. 99-109Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Paleo- and Mesoproterozoic fossil record of multicellular eukaryotes is scarce but extremely important in studying the evolution of life in the Precambrian Era. Typically, fossils heralded as ‘multicellular eukaryotes’ that are older than the Ediacaran are met with controversy. To confront such debates, we investigate the chemical, isotopic, and molecular structural characteristics of organic matter from carbonaceous compressions in the 1630 Ma Tuanshanzi Formation in northern China, some of the earliest putative macroscopic multicellular eukaryote fossils (Zhu and Chen, 1995). The large-size and relative complexity of these fossils and similar remains from the 1.56 Ga Gaoyuzhuang Formation have led to their interpretation as eukaryotes. Raman spectral parameters give an estimated peak-metamorphic temperature TMax in the range of 202–286 °C, confirming the good preservation of the organic remains. Two-dimensional Raman maps of the carbonaceous compressions show ultrastructural variations that suggest diverse subcellular compounds being consistent with multicellular eukaryotes. The organic matter has carbon isotopic composition δ13Corg-SIMS between −45.3 and −32.2‰, and a branching index of carbon chain measured by the micro-FTIR spectral parameter R3/2 between 0.17 and 0.31. Together with their large-size and morphology, the isotopic, geochemical and ultrastructural data supports an interpretation of the Tuanshanzi Formation carbonaceous compressions as derived from phototrophic, multicellular eukaryotic algae. Our data support the early evolution of macroscopic multicellular eukaryotes in the sulfidic and low-oxygen conditions that prevailed in the Paleo- and Mesoproterozoic oceans.

  • 2.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Haig, David W.
    Centre for Energy Geoscience, School of Earth Sciences, The University of Western Australia, Perth 6009, Australia.
    Siversson, Mikael
    Department of Earth and Planetary Sciences, Western Australian Museum, Welshpool, WA 6106, Australia.
    Einarsson, Elisabeth
    Department of Geology, Lund University, S-223 62 Lund, Sweden.
    Did mangrove communities exist in the Late Cretaceous of the Kristianstad Basin, Sweden?2018Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 498, s. 99-114Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Previous inferences of oyster-dominated communities occupying mangrove-like depositional settings in the Kristianstad Basin, Sweden, during the late early Campanian are reassessed. A significant percentage of oysters (Acutostrea incurva) from the Belemnellocamax mammillatus zone in Bed 3 at Åsen bear indentations on their left valves indicating attachment to plant axes. Many of these axes bear morphological features characteristic of the distal subaerial portions of woody plant branches and appear to have been rafted into the marine environment rather than representing in situ mangrove stems and roots. Foraminiferal assemblages recovered from sediment within the oyster body cavities differ from modern mangrove-community associations by the absence of siliceous agglutinated Foraminifera, the presence of diverse and relatively abundant Lagenida, relatively common triserial Buliminida, and a notable percentage of planktonic taxa. Chondrichthyan teeth assemblages from the same beds are similarly incompatible with the interpretation of a mangrove depositional environment based on comparisons with the distribution of related extant taxa. Apart from oyster shells and belemnite rostra, these beds are notably depauperate in diversity and abundance of macroinvertebrate remains compared with coeval carbonate shoal and rocky shoreline assemblages from the same basin. The collective palaeontological and sedimentological evidence favours an inner neritic sandy-substrate setting, but not nearshore or mangrove-like depositional environment for the oyster-rich Bed 3 at Åsen. The absence of mangrove-like assemblages at Åsen is consistent with the development of modern mangrove ecosystems much later (during the Maastrichtian and Cenozoic) based on the global palynological record.

  • 3.
    Laurie, John
    et al.
    Geoscience Australia, Canberra, Australia.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Mary Elizabeth White AM:5 January 1926 – 5 August 2018: Obituary2018Övrigt (Övrigt vetenskapligt)
    Abstract [en]

    Mary White was born in South Africa to an entomologist father and a botanist mother, but spent most of her early years in Southern Rhodesia (now Zimbabwe), where her father was First Director of Agriculture and Professor of Entomology. She attended the University of Cape Town, where she studied botany and zoology. When looking for a subject for her Masters' thesis, Alexander du Toit recommended a paleobotanical subject, as there was no paleobotanist in Africa but it had Gondwanan fossil flora awaiting study. This eventually led to Mary's lifetime interest in Gondwana and the evolution of its biota.

  • 4.
    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.

  • 5.
    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.

  • 6.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Pott, Christian
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Museum für Naturkunde Paläontologische Bodendenkmalpflege Sentruper Straße 285 48161 Münster.
    Sobbe, Ian H.
    Ancient Environments, Queensland Museum, PO Box 3300, South Brisbane, 4101 Qld, Australia, and School of Earth and Environmental Sciences, University of Queensland, St Lucia 4072, Australia.
    The diversity of Australian Mesozoic bennettitopsid reproductive organs2018Ingår i: Palaeobiodiversity and Palaeoenvironments, ISSN 1867-1594, E-ISSN 1867-1608, Vol. 98, s. 71-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Several dispersed reproductive organs of bennettitopsid gymnosperms are described and illustrated from Triassic to Cretaceous strata of Australia: Williamsonia eskensis sp. nov. (Middle Triassic), Williamsonia ipsvicensis sp. nov. (Upper Triassic), Williamsonia durikaiensis sp. nov. (Lower Jurassic), Williamsonia sp. (Lower Jurassic), Williamsonia rugosa sp. nov. (Middle Jurassic), Williamsonia gracilis sp. nov. (Lower Cretaceous), Cycadolepis ferrugineus sp. nov. (Lower Jurassic), Cycadolepis sp. (Lower Cretaceous), and Fredlindia moretonensis Shirley 1898 comb. nov. (Upper Triassic). Among these, W. eskensis appears to represent the oldest bennettitalean reproductive structure yet identified. Although global floras expressed less provincialism during the Mesozoic and many genera are cosmopolitan, Australian bennettopsid species appear to have been endemic based on the morphological characters of the reproductive structures. Bennettopsids have a stratigraphic range of around 210 million years in Australia and are widely and abundantly represented by leaf fossils, but only around 20 specimens of reproductive structures, of which half are attributed to Fredlindia, have been recovered from that continent’s geological archive. The extremely low representation of reproductive organs vis-à-vis foliage is interpreted to reflect a combination of physical disintegration of the seed-bearing units while attached to the host axis and, potentially, extensive vegetative reproduction in bennettopsids growing at high southern latitudes during the Mesozoic.

  • 7.
    Edirisooriya, Geetha
    et al.
    Department of Geology, University of Peradeniya, Peradeniya, Sri Lanka.
    Dharmagunawardhane, H.A.
    Department of Geology, University of Peradeniya, Peradeniya, Sri Lanka.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    The first record of the Permian Glossopteris flora from Sri Lanka: implications for hydrocarbon source rocks in the Mannar Basin2018Ingår i: Geological Magazine, ISSN 0016-7568, E-ISSN 1469-5081, Vol. 155, s. 907-920Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Strata exposed near Tabbowa Tank, Tabbowa Basin, western Sri Lanka have yielded the

    first representatives of the distinctive Permian Glossopteris flora from that country. The assemblage

    includes gymnosperm foliage attributable to Glossopteris raniganjensis, roots referable to Vertebraria

    australis, seeds assigned to Samaropsis sp., sphenophyte axes (Paracalamites australis) and

    foliage (Sphenophyllum emarginatum), and fern foliage (Dichotomopteris lindleyi). This small macroflora

    is interpreted to be of probable Lopingian (late Permian) age based on comparisons with the

    fossil floras of Peninsula India. Several Glossopteris leaves in the assemblage bear evidence of terrestrial

    arthropod interactions including hole feeding, margin feeding, possible lamina skeletonization,

    piercing-and-sucking damage and oviposition scarring. The newly identified onshore Permian strata

    necessitate re-evaluation of current models explaining the evolution of the adjacent offshore Mannar

    Basin. Previously considered to have begun subsiding and accumulating sediment during Jurassic

    time, we propose that the Mannar Basin may have initiated as part of a pan-Gondwanan extensional

    phase during late Palaeozoic – Triassic time. We interpret the basal, as yet unsampled, seismically

    reflective strata of this basin to be probable organic-rich continental strata of Lopingian age, equivalent

    to those recorded in the Tabbowa Basin, and similar to the Permian coal-bearing successions

    in the rift basins of eastern India and Antarctica. Such continental fossiliferous strata are particularly

    significant as potential source rocks for recently identified natural gas resources in the Mannar

    Basin.

  • 8. Rydland Pedersen, L.-E.
    et al.
    Staudigel, H.
    McLoughlin, N.
    Strauss, H.
    Whitehouse, Martin J.
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    A multiple sulfur isotope study through the volcanic section of the Troodos ophiolite.2017Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 468, s. 49-62Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Multiple S isotope systematics (δ34S and Δ33S) and high resolution in-situ S isotope measurements offer new perspectives on the study of biological and abiotic cycling of sulfur in hydrothermal systems. We applied these techniques to the Tethyian Troodos ophiolite (91 Ma) from Cyprus, one of the best-preserved remnants of oceanic crust in the world, using materials from deep drill cores and surface sampling. We focused on the volcanic section of the ophiolite, including the hydrothermal massive sulfide deposit at Agrokipia, which represents a fossil zone of high-temperature fluid upwelling, and the Akaki river section which displays a range of lower temperature alteration types.

    The δ34S and Δ33S values of bulk and SIMS (secondary ion mass spectrometry) analyses from the Agrokipia sulfide deposits show that the sulfide minerals are largely derived from thermochemical reduction of entrained seawater sulfate and leached H2S from the “root zone” of hydrothermal upwelling. The contributions of these two sources can vary substantially within individual sulfide grains, indicating a very dynamic mixing between these sulfur sources. Microbial reworking of the sulfide mound is recorded in a sample with very elevated Δ33S values (0.22‰).

    The Akaki and Agrokipia volcanics experienced low temperature sulfur loss and removal of heavier sulfur isotopes due to partial oxidation by microbes. While some intervals gained sulfur, and have δ34S and Δ33S values indicative of microbial sulfate reduction. REE-data of vein quartz containing pyrite with δ34S = ~− 21‰ implies local ephemeral hydrothermal upwelling in the lower Akaki volcanics, possibly associated with the late stage boninitic magmatic activity in the Troodos ophiolite, suggesting that microbial sulfate reduction in oceanic crust may continue for 10–15 Ma in crustal sections with prolonged igneous activity such as Troodos.

  • 9.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Antarctica’s Glossopteris forests2017Ingår i: 52 More Things You Should Know About Palaeontology / [ed] Cullum, A.; Martinius, A.W., Nova Scotia: Agile Libre , 2017, s. 22-23Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The Prince Charles Mountains (PCMs) of East Antarctica were first spotted

    from the air during The United States Navy Antarctic Developments Program

    'Operation Highjump' in 1946-47. but first visited nearly a decade later by

    Australian explorers. In the austral summer of 1994-95. Andrew Drinnan (University

    of Melbourne) and I ventured to the PCMs to search for fossil plants.

    Most of the rocks there are ancient - Archaean and Proterozoic granites and

    metamorphics - but one small area. the Amery Oasis. hosts Permian coal-rich

    strata and Triassic red-beds.

  • 10.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Australia's Permian vertebrates: where have they gone?2017Ingår i: Australian Age of Dinosaurs Magazine, ISSN 1448-4420, Vol. 14, s. 70-75Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    The Permian period (299–252 Million years old) is that time interval immediately before the rise of the dinosaurs. It began with an ice age and ended with the largest mass extinction event in Earth’s history. Australia’s Permian strata contain a rather meagre record of vertebrate fossils. Vertebrates are those animals with a backbone. In the modern world, that includes everything from fish to birds and mammals but, in the Permian, the vertebrate groups present were fish, amphibians and reptiles. Australia’s sparse vertebrate record stands in contrast to some other parts of the world, such as the Karoo Basin in South Africa, which is endowed with a rich record of bones and teeth, particularly from early mammal-like reptiles.

  • 11.
    Kustatscher, Evelyn
    et al.
    Museum of Nature South Tyrol, Bindergasse 1, 39100 Bozen/Bolzano, Italy.
    Ash, Sidney
    Department of Earth and Planetary Sciences, Northrop Hall, University of New Mexico, Albuquerque, NM 87131, USA.
    Karasev, Eugeny
    Borissiak Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya 123, Moscow 117647, Russia.
    Pott, Christian
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Yu, Jianxin
    State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, P.O.Box 430074, P.R. China.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Flora of The Late Triassic2017Ingår i: The Late Triassic World: Earth in a Time of Transition / [ed] Tanner, L.H., New York: Springer International Publishing , 2017, 1, s. 545-622Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The Triassic was a crucial period of botanical evolutionary innovations and plant diversification. Key plant groups (Bennettitales, Czekanowskiales, Gnetales and several modern fern and conifer families) originated during this span of time, together with some taxa putatively related to angiosperms. The composition of the various plant assemblages shows a more homogeneous flora globally than during the Permian. Nonetheless two major floristic provinces are distinguishable during the Late Triassic (Gondwana and Laurussia) together with several subprovinces (two within Gondwana, nine within Laurussia), based on palyno- and macro-floras.The latter are differentiated by contrasting taxonomic composition and group abundances related to different climatic and regional environmental conditions. Many plant families and genera are widely distributed in the Late Triassic, at least in the respective hemispheres. Based on the array of preserved damage types on leaves and wood, insect faunas appear to have recovered from the end-Permian mass extinction by the Late Triassic, with a major expansion of herbivory in Gondwana. All modern functional feeding groups (FFG) were present by the Triassic, including external foliage feeding, piercing-and-sucking, galling, leaf mining and seed predation, with some evidence for the development of very specialized feeding traits and egg-laying strategies.

  • 12.
    Vajda, Vivi
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Pucetaite, Milda
    Department of General Physics and Spectroscopy, Vilnius University, LT-102 57 Vilnius, Lithuania.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Engdahl, Anders
    MAX-IV laboratory, Lund University, SE-221 00 Lund, Sweden.
    Heimdal, Jimmy
    MAX-IV laboratory, Lund University, SE-221 00 Lund, Sweden.
    Uvdal, Per
    Chemical Physics, Department of Chemistry, Lund University, SE-222 41 Lund, Sweden.
    Molecular signatures of fossil leaves provideunexpected new evidence for extinct plant relationships2017Ingår i: Nature Ecology and Evolution, E-ISSN ISSN 2397-334X, Vol. 1, s. 1093-1099Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gene sequences form the primary basis for understanding the relationships among extant plant groups, but genetic data are unavailable from fossils to evaluate the affinities of extinct taxa. Here we show that geothermally resistant fossil cuticles of seed-bearing plants, analysed with Fourier transform infrared (FTIR) spectroscopy and hierarchical cluster analysis (HCA), retain biomolecular suites that consistently distinguish major taxa even after experiencing different diagenetic histories. Our results reveal that similarities between the cuticular biochemical signatures of major plant groups (extant and fossil) are mostly consistent with recent phylogenetic hypotheses based on molecular and morphological data. Our novel chemotaxonomic data also support the hypothesis that the extinct Nilssoniales and Bennettitales are closely allied, but only distantly related to Cycadales. The chemical signature of the cuticle of Czekanowskia (Leptostrobales) is strongly similar to that of Ginkgo leaves and supports a close evolutionary relationship between these groups. Finally, our results also reveal that the extinct putative araucariacean, Allocladus, when analysed through HCA, is grouped closer to Ginkgoales than to conifers. Thus, in the absence of modern relatives yielding molecular information, FTIR spectroscopy provides valuable proxy biochemical data complementing morphological characters to distinguish fossil taxa and to help elucidate extinct plant relationships.

  • 13.
    Pole, Mike
    et al.
    Queensland Herbarium, Brisbane Botanic Gardens Mt Coot-tha, Mt Coot-tha Rd, Toowong QLD 4066, Australia.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    The first Cenozoic Equisetum from New Zealand2017Ingår i: Geobios, ISSN 0016-6995, E-ISSN 1777-5728, Vol. 50, s. 259-265Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Equisetum is described for the first time from Cenozoic deposits of New Zealand. The fossils derive from two early to earliest middle Miocene assemblages in South Island, New Zealand. The fossils are ascribed tentatively to subgenus Equisetum based on their possession of whorled branch scars, but they cannot be assigned with confidence to a formal species. The decline of equisetaleans, otherwise unknown from the Cenozoic of the New Zealand-Australian-Antarctic domain, was possibly a consequence of severe environmental changes – particularly, abrupt shifts in the temperature and soil moisture regime – experienced by this region in the Neogene, coupled with competition from opportunistic angiosperms.

  • 14.
    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.

  • 15.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    A new genus of glossopterid fructifications from the Artinskian–Changhsingian of eastern Australia2016Ingår i: Ameghiniana, ISSN 0002-7014, E-ISSN 1851-8044, Vol. 53, s. 586-598Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new genus, Karingbalia is established to accommodate certain eastern Australian glossopterid fertile organs previously assigned to Ottokaria Zeiller emend. Pant et Nautiyal. Karingbalia differs from Ottokaria mainly by the sub-parallel rather than perpendicular orientation of basal peripheral lobes with respect to the receptacle margin. Moreover, Karingbalia ranges from the Artinskian to Changhsingian, whereas Ottokaria sensu stricto is probably confined to the Cisuralian. Two Karingbalia species are recognized: K. inglisensis McLoughlin comb. nov. from the Lopingian of the Bowen and Sydney basins; and K. nychumensis sp. nov. from Artinskian–lower Kungurian strata on the Georgetown Inlier. Several additional species of Ottokaria from across Gondwana do not conform precisely to the diagnosis of that genus and their taxonomic reappraisal is proposed.

  • 16.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Strullu-Derrien, Christine
    Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
    Biota and palaeoenvironment of a high middle-latitude Late Triassic peat-forming ecosystem from Hopen, Svalbard archipelago2016Ingår i: Geological Society, London, Special Publications, ISSN 0305-8719, Vol. 434, s. 87-112Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A siliceous permineralized peat block recovered from Hopen in the Svalbard archipelago hosts a low-diversity Late Triassic flora dominated by autochthonous roots and stems of bennettitaleans and lycophytes, and parautochthonous leaves, sporangia, spores and pollen from a small range of pteridophytes and gymnosperms. Some parenchymatous bennettitalean root cells show interactions with chytrid fungi and bacteria; the remains of other fungi and fungi-like organisms are dispersed within the peat’s detrital matrix. Cavities excavated through some roots and compacted detritus contain abundant coprolites probably derived from sapro-xylophagous oribatid mites, although no body fossils have yet been identified. Sparse larger coprolites containing leaf fragments attest to the presence of invertebrate folivores in the ancient ecosystem. The low diversity flora, relatively few trophic levels and simple nutritional web, together with sedimentological aspects of the host formation and the peat structure, collectively favour accumulation of the organic mass as a fibric (root-dominated) peat within a temperate (high middle-latitude), well aerated mire.

  • 17.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Biotic interactions in an exceptionallywell preserved osmundaceous fern rhizome from the Early Jurassic of Sweden2016Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, s. 86-96Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A remarkably well permineralized osmundaceous rhizome from the Early Jurassic of southern Sweden yields evidence of an array of interactions with other organisms in its immediate environment. These include epiphytism by a herbaceous heterosporous lycopsid; putative oribatid mite herbivory and detritivory (petiole and detritus borings and coprolites); potential pathogenic, saprotrophic or mycorrhizal interactions between fungi and the host plant and its epiphytes; parasitism or saprotrophy by putative peronosporomycetes; and opportunistic or passivemycophagy by oribatid mites evidenced by fungal spores in coprolites. A combination of abrupt burial by lahar deposits and exceedingly rapid permineralization by precipitation of calcite from hydrothermal brines facilitated the exquisite preservation of the rhizome and its component community of epiphytes, herbivores, saprotrophs and parasites. Ancient ferns with a rhizome cloaked by a thick mantle of persistent leaf bases and adventitious roots have a high potential for preserving macro-epiphytes and associated micro-organisms, and are especially promising targets for understanding the evolution of biotic interactions in forest understorey ecosystems.

  • 18.
    Vajda, Vivi
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Linderson, Hans
    Geology Department, University of Lund.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Disrupted vegetation as a response to Jurassic volcanism in southern Sweden2016Ingår i: Geological Society of London Special Publications, ISSN ISSN 0305-8719, Vol. 434, s. 127-147Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Central Skåne (Scania) in southern Sweden hosts evidence of extensive Jurassic volcanism in the form of mafic volcanic plugs and associated volcaniclastic deposits that entomb well preserved macro-plant and spore–pollen assemblages. Palynological assemblages recovered from the Höör Sandstone are of Hettangian–Pliensbachian age and those from the overlying lahar deposits are dated as Pliensbachian–early Toarcian (?). Palynomorph assemblages from these units reveal significantly different ecosystems, particularly with respect to the gymnospermous components that represented the main canopy plants. Both palynofloras are dominated by osmundacean, marattiacean and cyatheacean fern spore taxa but, whereas the Höör Sandstone hosts abundant Chasmatosporites spp. pollen produced by plants related to cycadophytes, the volcanogenic deposits are dominated by cypress family pollen (Perinopollenites) with an understorey component rich in putative Erdtmanithecales (or possibly Gnetales), and collectively representing vegetation of disturbed habitats. Permineralized conifer wood attributed to Protophyllocladoxylon sp., belonging to plants that probably produced the abundant Perinopollenites grains, is abundant in the volcanigenic strata, and shows sporadic intraseasonal and multi-year episodes of growth disruption. Together with the relatively narrow but marked annual growth rings, and the annual and mean sensitivity values that span the complacent–sensitive domains, these features suggest growth within Mediterranean-type biomes subject to episodic disturbance.

  • 19.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Exceptional fossils and biotas of Gondwana: the fortieth anniversary issue of Alcheringa2016Ingår i: Alcheringa, ISSN 0311-5518, E-ISSN 1752-0754, Vol. 40, s. 399-406Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Alcheringa is now a truly international palaeontological journal. Although the early issues had a strong focus on Australasian fossil material, recent issues have published papers on material from all parts of the globe. As part of Alcheringa’s continuing editorial initiatives, and in light of the prominent role the journal has played in promoting the palaeontology of the Southern Hemisphere, we devote the final issue of volume 40 to the theme of ‘Exceptional fossils and biotas of Gondwana’. This issue includes a selection of invited papers dealing with a broad geographic and stratigraphic array of Southern Hemisphere fossils that have special historical, biostratigraphical, palaeoecogical or biogeographical significance. This theme extends to the documentation of exceptionally preserved ‘whole biotas’ from Gondwana.

  • 20.
    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.

  • 21.
    Gouramanis, Chris
    et al.
    Earth Observatory of Singapore, Nanyang Technological University, Singapore, 639798.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Siluro-Devonian trace fossils from the Mereenie Sandstone, Kings Canyon, Watarrka National Park, Amadeus Basin, Northern Territory, Australia2016Ingår i: Alcheringa, ISSN 0311-5518, E-ISSN 1752-0754, Vol. 40, s. 118-128Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nine trackways referable to the ichnogenus Diplichnites are preserved in the upper Silurian to Lower Devonian Mereenie Sandstone at Kings Canyon, Watarrka National Park, Northern Territory, Australia. Eight trackways are consistent with earlier descriptions of D. gouldi, and one trackway could not be assigned to an ichnospecies. The trackways are co-preserved with a range of sub-horizontal burrows referable to Beaconites and Taenidium, and several vertical burrows, surficial circular traces and a horizontal trail of uncertain identities. The ichnofossil assemblage highlights the diversity of animals present in the late Silurian to Lower Devonian paralic to fluvial environments of central Australia at the time of early colonization of the land’s surface. The assemblage is similar to ichnofaunas from coeval strata elsewhere in Australia and throughout Gondwana, and it highlights the potential of this region for further ichnological studies to elucidate the early stages of terrestrialization in the palaeoequatorial belt.

  • 22.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bomfleur, Benjamin
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Thomas, Mörs
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    The wierd world of fossil worm cocoons2016Ingår i: Deposits Magazine, ISSN ISSN 1744-9588, Vol. 46, s. 399-406Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Curious fossils in continental sedimentary strata that range from about a millimetre in diameter up to the size of a fingernail and appear to have a net-like coating on the surface have reported for over 150 years and have been variously interpreted as the eggs of insects, parts of lichens, the food-catching devices of ancient invertebrates, the membranous coatings of seeds, or the linings of clubmoss sporangia. Many early palaeobiologists simply labelled them as ‘red eggs’ and avoided assigning them to any particular biological group. However, these fossils match the characteristics of the egg-bearing cocoons of modern leeches and their relatives. During cocoon secretion, micro-organisms from the surrounding environment can become entrapped and entombed in the sticky threads of the cocoon wall, thus escaping decay, and ultimately becoming part of the fossil record.

  • 23.
    Anderson, Heidi
    et al.
    Dorrigo, NSW, Australia.
    David J. Batten, David
    Manchester University.
    Cantrill, David
    National Herbarium of Victoria, Royal Botanic Gardens Melbourne.
    Cleal, Christopher
    Museum of Wales.
    Susanne Feist-Burkhardt, Susanne
    SFB Geological Consulting & Services, Odenwaldstrasse 18, D-64372 Ober-Ramstadt, Germany.
    Fensome, Robert
    Natural Resources Canada.
    Head, Martin
    Brock University, Canada.
    Herendeen, Patrick
    Chicago Botanuic Garden.
    Jaramillo, Carlos
    Smithsonian Institution.
    Kvaček, Jiří
    Czech National Museum, Prague.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Skog, Judith
    George Mason University.
    Takahashi, Masamichi
    Niigata University.
    Wicander, Reed
    Department of Earth and Atmospheric Sciences, Central Michigan University .
    (087–090) Proposal to treat the use of a hyphen in the name of a fossil-genus as an orthographical error2015Ingår i: Taxon, ISSN 0040-0262, E-ISSN 1996-8175Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose modifications to the Code such that use of a hyphen in the name of a fossil-genus is treated as an error to be corrected by deletion of the hyphen. This will circumvent the need to conserve the numerous de-hyphenated names against unused hyphenated forms. We propose changes to Art. 60 of the Code to allow this correction, and the addition of a phrase in Art. 20 to add clarity to the naming of fossil-genera.

  • 24.
    Slater, Ben
    et al.
    School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hilton, Jason
    School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK.
    A high-latitude Gondwanan lagerstätte: The Permian permineralised peat biota of the Prince Charles Mountains, Antarctica2015Ingår i: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 27, s. 1446-1473Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Toploje Member chert is a Roadian to Wordian autochthonous–parautochthonous silicified peat preserved within the Lambert Graben, East Antarctica. It preserves a remarkable sample of terrestrial life from highlatitude central Gondwana prior to the Capitanian mass extinction event from both mega- and microfossil evidence that includes cryptic components rarely seen in other fossil assemblages. The peat layer is dominated by glossopterid and cordaitalean gymnosperms and containsmoderately common herbaceous lycophytes, together with a broad array of dispersed organs of ferns and other gymnosperms. Rare arthropod–plant and fungal–plant interactions are preserved in detail, together with a plethora of fungal morphotypes, Peronosporomycetes, arthropod remains and a diverse coprolite assemblage. Comparisons to other Palaeozoic ecosystems show that the macro flora is of low diversity. The fungal and invertebrate–plant associations demonstrate that a multitude of ecological interactions were well developed by the Middle Permian in high-latitude forest mires that contributed to the dominant coal deposits of the Southern Hemisphere. Quantitative analysis of the constituents of the silicified peat and of macerals within adjacent coal seams reveals that whilst silicified peats provide an unparalleled sample of the organisms forming Permian coals, they do not necessarily reflect the volumetric proportions of constituents within the derived coal. The Toploje Member chert Lagerstätte provides a snapshot of a rapidly entombed mire climax ecosystem in the closing stages of the Palaeozoic, but prior to the onset of the protracted crisis that engulfed and overthrew these ecosystems at the close of the Permian.

  • 25.
    Tosolini, Anne-Marie
    et al.
    School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Wagstaff, Barbara
    School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia.
    Cantrill, David
    National Herbarium of Victoria, Royal Botanic Gardens Melbourne, South Yarra, Victoria 3141, Australia.
    Galagher, Stephen
    School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia.
    Cheirolepidiacean foliage and pollen from Cretaceous high-latitudes of southeastern Australia2015Ingår i: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 27, s. 960-977Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cheirolepidiaceae leaves and pollen are recorded from Valanginian–Albian strata of southeastern Australia that were deposited at high-latitudes under cool, moist climates in contrast to the semi-arid or coastal habitats preferred by many northern Gondwanan and Laurasian representatives of this group. Leaves of this family are characterized by thick cuticles and cyclocytic stomata with randomly oriented apertures, arranged in scattered or longitudinal rows or bands. Stomata are deeply sunken and surrounded by four to six subsidiary cells that bear one or two ranks of prominent overarching papillae, which may constrict the mouth of the pit. Three new taxa (Otwayia denticulata Tosolini, Cheirolepidiaceae cuticle sp. A and sp. B) are distinguished based on cuticular features, adding to several previously documented cheirolepid conifers in the Early Cretaceous of eastern Australia. Cheirolepidiaceae foliage is preserved predominantly in fluvial floodbasin settings and is interpreted to be derived from small trees occupying disturbed or low-nutrient sites. The foliage is associated with Classopollis/Corollina pollen and roots characterized by prominent mycorrhizal nodules. A Cenomanian Classopollis type recognised from Bathurst Island, Northern Australia, is recorded for the first time from the Early Cretaceous Eumeralla Formation, Otway Basin. Classopollis locally is rare in Valanginian–Barremian strata of Boola Boola, Gippsland, but constitutes up to 14% of the palynomorph assemblage in Albian strata. This indicates that the family was locally abundant in cool southern high-latitude climates of the Mesozoic, contrary to previous reports of its rarity in this region.

  • 26.
    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.

  • 27.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Homonymy of genera2015Ingår i: Australasian Systematic Botany Society Newsletter, ISSN 2204-910X, nr 162-163, s. 8-11Artikel, forskningsöversikt (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Philip Short recently faced the problem of having established a plant genus that turned out to be a homonym of an earliernamed genus. In 2014, he erected the name Roebuckia for a range of daisy species in his review of Brachyscome. However, Roebuckia had already been established as a name for a fossil (Early Cretaceous) plant from Western Australia by myself (McLoughlin, 1996). Because homonyms are illegitimate according to the International Code of Nomenclature for Algae, Fungi and Plants (McNeill et al., 2012), Philip was obliged to establish a new name (Roebuckiella) for those species he had previously assigned to Roebuckia (see Short, 2015). How, then, can one be sure that when establishing a new genus, the chosen name has not been used before?

  • 28.
    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.

  • 29.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Drinnan, Andrew
    School of Botany, The University of Melbourne, Parkville, Victoria 3052, Australia.
    Slater, Ben
    School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK.
    Hilton, Jason
    School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK.
    Paurodendron stellatum: a new Permian permineralized herbaceous lycopsid from the Prince Charles Mountains, Antarctica2015Ingår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 220, s. 1-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diminutive, silica-permineralized lycopsid axes, from a Guadalupian (Middle Permian) silicified peat in the Bainmedart Coal Measures of East Antarctica are described and assigned to Paurodendron stellatum sp. nov. Axes consist only of primary-growth tissues with a vascular system characterized by an exarch actinostele with 6–20 protoxylem points. Stems have a relatively narrow cortex of thin-walled cells that are commonly degraded, but the root cortex typically contains more robust, thick-walled cells. The stems bear helically inserted, elliptical–rhombic, ligulate microphylls. Roots possess an eccentrically positioned monarch vascular strand. Paurodendron stellatum is one of a very small number of anatomically preserved lycopsid axes described from the Gondwanan Permian and represents the first post-Carboniferous record of this genus. Based on dispersed vegetative remains, megaspores and microspores, herbaceous lycopsids, such as P. stellatum, appear to have been important understorey components of both low- and high-latitude mire forests of the late Palaeozoic.

  • 30.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    The Landsborough Sandstone: the Sunshine Coast’s Jurassic park2015Ingår i: Australian Age of Dinosaurs Journal, ISSN 1448-4420, Vol. 12, s. 78-82Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Formed by lava thrusting up through sandstone bedrock 25 million years ago, the Glasshouse Mountains form an imposing backdrop to farming country in the Sunshine Coast Hinterland. Deposited in the Early Jurassic Period, this rock formation—known as the Landsborough Sandstone—forms the bedrock for most of the coastal plain from Brisbane’s northern suburbs to Coolum and hosts a range of fossil plants including ferns, seed-ferns and conifers.

  • 31.
    Tewari, Rajni
    et al.
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Ram- Awatar, Ram-
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Pandita, Sundeep
    Department of Geology, University of Jammu, Jammu-180006, India.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Agnihotri, Deepa
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Pillai, Suresh
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Singh, Vartika
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Kumar, Kamlesh
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Bhat, Ghulam
    Directorate of Geology and Mining, Jammu and Kashmir Government, Srinagar, India.
    The Permian-Triassic palynological transition in the Guryul Ravine section, Kashmir, India: implications for Tethyan – Gondwanan correlations2015Ingår i: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 149, s. 53-66Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This first palynological study of the Permian–Triassic succession in the Guryul Ravine, Kashmir, India, reveals impoverished latest Permian spore-pollen assemblages in the uppermost Zewan Formation, a rich palynoassemblage from the basal Khunamuh Formation characteristic of the Permian–Triassic transition zone and depleted Triassic assemblages from higher in the Khunamuh Formation. The collective assemblages can be broadly correlated to the Densipollenites magnicorpus and Klausipollenites decipiens palynozones of peninsular India and to palynofloras spanning the Permian–Triassic boundary elsewhere in Gondwana. Generally, low spore-pollen yields and poor preservational quality of the studied assemblages hinder more precise correlations and are inferred to be a function of an offshore marine depositional setting on the margin of the Neotethys Ocean, and thermal alteration associated with Cenozoic collisional tectonism between India and Asia.

  • 32.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Martin, Sarah
    Geological Survey of Western Australia, Department of Mines and Petroleum.
    The record of Australian Jurassic plant-arthropod interactions2015Ingår i: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 27, s. 940-959Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A survey of Australian Jurassic plant fossil assemblages reveals examples of foliar andwood damage generated by terrestrial arthropods attributed to leaf-margin feeding, surface feeding, lamina hole feeding, galling, piercingand-sucking, leaf-mining, boring and oviposition. These types of damage are spread across a wide range of fern and gymnosperm taxa, but are particularly well represented on derived gymnosperm clades, such as Pentoxylales and Bennettitales. Several Australian Jurassic plants show morphological adaptations in the form of minute marginal and apical spines on leaves and bracts, and scales on rachises that likely represent physical defences against arthropod herbivory. Only two entomofaunal assemblages are presently known from the Australian Jurassic but these reveal a moderate range of taxa, particularly among the Orthoptera, Coleoptera, Hemiptera and Odonata, all of which are candidates for the dominant feeding traits evidenced by the fossil leaf and axis damage. The survey reveals that plant–arthropod interactions in the Jurassic at middle to high southern latitudes of southeastern Gondwana incorporated a similar diversity of feeding strategies to those represented in coeval communities from other provinces. Further, the range of arthropod damage types is similar between Late Triassic and Jurassic assemblages from Gondwana despite substantial differences in the major plant taxa, implying that terrestrial invertebrate herbivoreswere able to successfully transfer to alternative plant hosts during the floristic turnovers at the Triassic–Jurassic transition.

  • 33.
    Qu, Yuangao
    et al.
    Department of Earth Science and Centre for Geobiology, University of Bergen, Norway.
    Engdahl, Anders
    MAX IV Laboratory, Lund University, Sweden.
    Zhu, Shixing
    Tianjin Institute of Geology and Mineral Resources, CGS, China.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    McLoughlin, Nicola
    Department of Geology, Lund University, Sweden.
    Ultrastructural heterogeneity of carbonaceous material in ancient cherts: investigating biosignature origin and preservation2015Ingår i: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 15, nr 10, s. 825-842Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Opaline silica deposits on Mars may be good target sites where organic biosignatures could be preserved. Potential analogues on Earth are provided by ancient cherts containing carbonaceous material (CM) permineralized by silica. In this study, we investigated the ultrastructure and chemical characteristics of CM in the Rhynie chert (c. 410 Ma, UK), Bitter Springs Formation (c. 820 Ma, Australia), and Wumishan Formation (c. 1485 Ma, China). Raman spectroscopy indicates that the CM has experienced advanced diagenesis or lowgrade metamorphism at peak metamorphic temperatures of 150–350C. Raman mapping and micro-Fourier transform infrared (micro-FTIR) spectroscopy were used to document subcellular-scale variation in the CM of fossilized plants, fungi, prokaryotes, and carbonaceous stromatolites.

    In the Rhynie chert, ultrastructural variation in the CM was found within individual fossils, while in coccoidal and filamentous microfossils of the Bitter Springs and formless CM of the Wumishan stromatolites ultrastructural variation was found between, not within, different microfossils. This heterogeneity cannot be explained by secondary geological processes but supports diverse carbonaceous precursors that experienced differential graphitization. Micro-FTIR analysis found that CM with lower structural order contains more straight carbon chains (has a lower R3/2 branching index) and that the structural order of eukaryotic CM is more heterogeneous than prokaryotic CM.

    This study demonstrates how Raman spectroscopy combined with micro-FTIR can be used to investigate the origin and preservation of silica-permineralized organics. This approach has good capability for furthering our understanding of CM preserved in Precambrian cherts, and potential biosignatures in siliceous deposits on Mars. Key

  • 34.
    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.

  • 35.
    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.

  • 36.
    Pott, Christian
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Divaricate growth habit in Williamsoniaceae (Bennettitales): Unravelling the ecology of a key Mesozoic plant group2014Ingår i: Palaeobiodiversity and Palaeoenvironments, ISSN 1867-1594, Vol. 94, nr 2, s. 307-325Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Representatives of Williamsoniacae (Bennettitales) are usually restored as small-leafed shrubs or low-growing trees with densely interlaced stems bifurcating or trifurcating at broad angles —a growth form referred to as divaricating. A divaricate plant architecture has evolved independently in at least 18 modern plant families, of which the majority occur in New Zealand, where they constitute more than 10 % of the flora. Botanists favour two or three hypotheses on the benefits of a divaricating habit for modern plants. One hypothesis favours the evolution of this habit to protect the foliage and reproductive structures from browsing by large mammals or large flightless birds, such as the recently extinct moa or other ratites. Another argues that this habit evolved in response to a dry, windy or frosty climate, whereas a third regards divarication as having evolved to optimise foliar light harvesting. Our evaluation of these hypotheses with respect to the ecological pressures known to have been experienced by Williamsoniaceae in the mid-Mesozoic reveals that although defence against browsing tetrapods cannot be excluded as a selective pressure that promoted divarication in Williamsoniaceae, many of the anatomical and morphological features of this family appear to represent responses to local environmental conditions. In this context, representatives of Williamsoniaceae have many characters that are convergent with members of Banksiinae (Proteaceae), suggesting adaptation to open vegetation communities on nutrient-deficient soils.

  • 37.
    CARPENTER, RAYMOND
    et al.
    University of Tasmania.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    HILL, ROBERT
    University of Adelaide.
    McNAMARA, KENNETH
    University of Cambridge.
    JORDAN, GREGORY
    University of Tasmania.
    EARLY EVIDENCE OF XEROMORPHY IN ANGIOSPERMS: STOMATAL ENCRYPTION IN A NEW EOCENE SPECIES OF BANKSIA (PROTEACEAE) FROM WESTERN AUSTRALIA2014Ingår i: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 101, nr 9, s. 1486-1497Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Premise of the study: Globally, the origins of xeromorphic traits in modern angiosperm lineages are obscure but are thought to be linked to the early Neogene onset of seasonally arid climates. Stomatal encryption is a xeromorphic trait that is prominent in Banksia , an archetypal genus centered in one of the world’s most diverse ecosystems, the ancient infertile landscape of Mediterranean-climate southwestern Australia.

    Methods: We describe Banksia paleocrypta , a sclerophyllous species with encrypted stomata from silcretes of the Walebing and Kojonup regions of southwestern Australia dated as Late Eocene.

    Key results: Banksia paleocrypta shows evidence of foliar xeromorphy ~20 Ma before the widely accepted timing for the onset of aridity in Australia. Species of Banksia subgenus Banksia with very similar leaves are extant in southwestern Australia. The conditions required for silcrete formation infer fl uctuating water tables and climatic seasonality in southwestern Australia in the Eocene, and seasonality is supported by the paucity of angiosperm closed-forest elements among the fossil taxa preserved with B. paleocrypta. However, climates in the region during the Eocene are unlikely to have experienced seasons as hot and dry as present-day summers.

    Conclusions: The presence of B. paleocrypta within the center of diversity of subgenus Banksia in edaphically ancient southwestern Australia is consistent with the continuous presence of this lineage in the region for ≥ 40 Ma, a testament to the success of increasingly xeromorphic traits in Banksia over an interval in which numerous other lineages became extinct.

  • 38.
    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.

  • 39.
    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.

  • 40.
    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.

  • 41.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Jansson, Ida-Maria
    Lund University.
    Vajda, Vivi
    Lund University.
    Megaspore and microfossil assemblages reveal diverse herbaceous lycophytes in the Australian Early Jurassic flora2014Ingår i: Grana, ISSN 0017-3134, Vol. 53, s. 22-53Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here, we describe and illustrate by transmitted light and scanning electron microscopy the first Australian Jurassic megaspore assemblages. The megaspores and other mesofossils were isolated from terrestrial deposits of the Marburg Subgroup (late Pliensbachian) at Inverleigh Quarry, Clarence-Moreton Basin, eastern Australia. Nine megaspore taxa are identified including one new species: Paxillitriletes rainei. Miospore assemblages recovered from the same samples at Inverleigh reveal a slightly higher diversity of lycophyte microspores. The collective megaspore suite from Inverleigh shares several genera with mid-Mesozoic assemblages from widely distributed parts of the world, but most of the Inverleigh species have subtle morphological differences from congeneric forms elsewhere. The megaspores accumulated in fluvial floodplain facies and are associated with mostly dissociated isoetalean leaf debris. Other mesofossils in the sampled interval include annelid egg cases, dispersed seeds and charcoal. Invertebrate burrows and possible vertebrate tracks also occur in this succession. Lycophyte macrofossils are otherwise known from only two other Australian Jurassic deposits. The richness of the megaspore and microspore suites attest to a significant diversity of lycophytes in the Australian Jurassic floras not hitherto appreciated from described macrofloras

  • 42. Rößler, Rössler
    et al.
    Philippe, Marc
    van Konijnenburg-van Cittert, Han
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Sakala, Jakub
    Zijlstra, Gea
    Which name(s) should be used for Araucaria-likefossil wood? – Results of a poll2014Ingår i: Taxon, ISSN 0040-0262, E-ISSN 1996-8175, Vol. 63, s. 177-184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.

  • 43. Slater, Ben J
    et al.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hilton, Jason
    Peronosporomycetes (Oomycota) from a Middle Permian permineralised peat within the Bainmedart Coal Measures, Prince Charles Mountains, Antarctica.2013Ingår i: PloS one, ISSN 1932-6203, Vol. 8, nr 8, s. e70707-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The fossil record of Peronosporomycetes (water moulds) is rather sparse, though their distinctive ornamentation means they are probably better reported than some true fungal groups. Here we describe a rare Palaeozoic occurrence of this group from a Guadalupian (Middle Permian) silicified peat deposit in the Bainmedart Coal Measures, Prince Charles Mountains, Antarctica. Specimens are numerous and comprise two morphologically distinct kinds of ornamented oogonia, of which some are attached to hyphae by a septum. Combresomyces caespitosus sp. nov. consists of spherical oogonia bearing densely spaced, long, hollow, slender, conical papillae with multiple sharply pointed, strongly divergent, apical branches that commonly form a pseudoreticulate pattern under optical microscopy. The oogonia are attached to a parental hypha by a short truncated stalk with a single septum. Combresomyces rarus sp. nov. consists of spherical oogonia bearing widely spaced, hollow, broad, conical papillae that terminate in a single bifurcation producing a pair of acutely divergent sharply pointed branches. The oogonium bears a short truncate extension where it attaches to the parental hypha. We propose that similarities in oogonium shape, size, spine morphology and hyphal attachment between the Permian forms from the Prince Charles Mountains and other reported Peronosporomycetes from Devonian to Triassic strata at widely separated localities elsewhere in the world delimit an extinct but once cosmopolitan Palaeozoic to early Mesozoic branch of the peronosporomycete clade. We name this order Combresomycetales and note that it played an important role in late Palaeozoic and early Mesozoic peatland ecosystems worldwide.

  • 44. Dyer, Adrian G
    et al.
    Boyd-Gerny, Skye
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Rosa, Marcello G P
    Simonov, Vera
    Wong, Bob B M
    Parallel evolution of angiosperm colour signals: common evolutionary pressures linked to hymenopteran vision.2012Ingår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 279, nr 1742, s. 3606-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Flowering plants in Australia have been geographically isolated for more than 34 million years. In the Northern Hemisphere, previous work has revealed a close fit between the optimal discrimination capabilities of hymenopteran pollinators and the flower colours that have most frequently evolved. We collected spectral data from 111 Australian native flowers and tested signal appearance considering the colour discrimination capabilities of potentially important pollinators. The highest frequency of flower reflectance curves is consistent with data reported for the Northern Hemisphere. The subsequent mapping of Australian flower reflectances into a bee colour space reveals a very similar distribution of flower colour evolution to the Northern Hemisphere. Thus, flowering plants in Australia are likely to have independently evolved spectral signals that maximize colour discrimination by hymenoptera. Moreover, we found that the degree of variability in flower coloration for particular angiosperm species matched the range of reflectance colours that can only be discriminated by bees that have experienced differential conditioning. This observation suggests a requirement for plasticity in the nervous systems of pollinators to allow generalization of flowers of the same species while overcoming the possible presence of non-rewarding flower mimics.

  • 45.
    McLoughlin, Stephen
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Carpenter, Raymond J
    Jordan, Gregory J
    Hill, Robert S
    Seed ferns survived the end-Cretaceous mass extinction in Tasmania.2008Ingår i: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 95, nr 4, s. 465-71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Seed ferns, dominant elements of the vegetation in many parts of the world from the Triassic to Cretaceous, were considered to have disappeared at the end of the Cretaceous together with several other groups that had occupied key positions in terrestrial and marine ecosystems such as dinosaurs, plesiosaurs, and ammonoids. Seed-fern demise is generally correlated with competition from diversifying flowering plants through the Cretaceous and the global environmental crisis related to the Chicxulub impact event in the paleotropics at the end of the period. New fossils from Tasmania show that one seed-fern lineage survived into the Cenozoic by at least 13 million years. These fossils are described here as a new species, Komlopteris cenozoicus. Komlopteris is a genus of seed ferns attributed to Corystospermaceae and until now was not known from sediments younger than the Early Cretaceous. Discovery of this "Lazarus taxon," together with the presence of a range of other relictual fossil and extant organisms in Tasmania, other southern Gondwanan provinces, and some regions of northern North America and Asia, underscores high-latitude regions as biodiversity refugia during global environmental crises and highlights their importance as sources of postextinction radiations.

  • 46.
    Vajda, Vivi
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Extinction and recovery patterns of the vegetation across the Cretaceous–Palaeogene boundary — a tool for unravelling the causes of the end-Permian mass-extinction2007Ingår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 144, s. 99-112Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High-resolution palynofloral signatures through the Cretaceous–Palaeogene boundary succession show several features in common with the Permian–Triassic transition but there are also important differences. Southern Hemisphere Cretaceous–Palaeogene successions, to date studied at high resolution only in New Zealand, reveal a diverse palynoflora abruptly replaced by fungi-dominated assemblages that are in turn succeeded by low diversity suites dominated by fern spores, then gymnosperm- and angiosperm-dominated palynofloras of equivalent diversity to those of the Late Cretaceous. This palynofloral signature is interpreted to represent instantaneous (days to months) destruction of diverse forest communities associated with the Chicxulub impact event. The pattern of palynofloral change suggests wholesale collapse of vascular plant communities and short-term proliferation of saprotrophs followed by relatively rapid successional recovery of pteridophyte and seed–plant communities. The Permian–Triassic transition records global devastation of gymnosperm-dominated forests in a short zone synchronous with one or more peaks of the fungal/algal palynomorph Reduviasporonites. This zone is typically succeeded by assemblages rich in lycophyte spores and/or acritarchs. Higher in the succession, these assemblages give way to diverse palynofloras dominated by new groups of gymnosperms. Although different plant families were involved in the mass-extinctions, the general pattern of extinction and recovery is consistent between both events. The major difference is the longer duration for each phase of the Triassic recovery vegetation compared to that of the Paleocene. The protracted extinction-recovery succession at the Permian–Triassic boundary is incompatible with an instantaneous causal mechanism such as an impact of a celestial body but is consistent with hypotheses invoking extended environmental perturbations through flood-basalt volcanism and release of methane from continental shelf sediments.

  • 47. Vajda, Vivi
    et al.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Fungal proliferation at the Cretaceous-Tertiary boundary.2004Ingår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 303, nr 5663, s. 1489-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have found that a fungal spike occurs between the diverse Late Cretaceous palynoflora and the low-diversity fern-dominated early Paleocene assemblages in a New Zealand section. The fungal layer is coincident with the Ir anomaly marking the extinction event.

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