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  • 1.
    Arvestål, Emma
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new species of Cyrtograptus (Graptoloidea) from the Llandovery of Västergötland (Sweden)2011In: The 2nd Wiman Meeting: Carl Wiman's Legacy: 100 years of Swedish Palaeontology, Uppsala, 2011, 2-2 p.Conference paper (Refereed)
    Abstract [en]

    A new species of the genus Cyrtograptus from the late Llandovery of southern Sweden (Västergötland) is presented. The new species has been found near the top of Kinnekulle (Högkullen) in the Retiolites Shales, which are part of the lapworthi zone (late Telychian). Although it resembles the coeval C. lapworthi in appearance, a detailed comparison of the type material of C. lapworthi revealed distinct differences: the new species is more openly coiled in the proximal part, has a larger Two Thecae Repeat Distance (2TRD), and, most significantly, bears a second order cladium. Second order cladia are unknown from C. lapworthi. The new species is also compared with other species of Cyrtograptus that are characterized by second order cladia, such as the cotemporaneous C. laqueus and the slightly younger C. insectus (insectus zone; latest Telychian). However, C. laqueus differs from the new species in having a lower number of thecae separating the cladia, and also by the appearance of its proximal part, which forms a loop by crossing its own main stipe. C. insectus differs by having wider spaced cladia and a stronger coiled proximal part. Furthermore, the need of a redefinition of C. lapworthi is highlighted, due to the large morphological variations within this species.

  • 2.
    Arvestål, Emma
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Cyrtograptids from the Telychian (upper Llandovery) of Kinnekulle Mountain, southern Sweden2012Conference paper (Other academic)
  • 3.
    Arvestål, Emma
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Cyrtograptids from the Telychian (upper Llandovery) of Kinnekulle Mountain, southern Sweden2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, 45-56 p.Article in journal (Refereed)
    Abstract [en]

    The late Llandovery graptolite fauna of the Retiolites Shales on Kinnekulle Mountain in the province of Västergötland has long been known but never illustrated or studied in detail. New collections of graptolites from an interval at the very top of the exposed succession confirm previous reports of cyrtograptids, which make the shales on Kinnekulle the youngest preserved Palaeozoic rocks in the area. The co-occurrence of Oktavites spiralis and Cyrtograptus lapworthi constrains the strata to the lower lapworthi Biozone of the upper Telychian. The associated graptolite fauna comprises numerous monograptids and Retiolites angustidens as well as Cyrtograptus kinnekullensis n. sp., characterised by its open coiling and the presence of a second-order cladium on the second thecal cladium. This early occurrence of a cyrtograptid species with a second-order cladium on Baltica matches evolutionary patterns observed in Laurentia, suggesting that the ability to grow cladia of both first and higher order evolved approximately, synchronously and at the very beginning of cyrtograptid evolution.

  • 4.
    Balthasar, Uwe
    et al.
    University of Glasgow.
    Brazeau, Martin
    Brock, Glenn
    Macquarie University, Australia.
    Harper, David
    Durham University.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    McGowan, Alistair
    Skovsted, Christian B.
    Naturhistoriska Riksmuseet.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Zhang, Zhifei
    Northwest University, Xi'an.
    Early evolution of biomineralization in brachiopods2012Conference paper (Other academic)
  • 5.
    Balthasar, Uwe
    et al.
    University of Glasgow.
    Brazeau, Martin
    Brock, Glenn
    Macquarie University, Australia.
    McGowan, Alistair
    Harper, David
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Skovsted, Christian B.
    Naturhistoriska Riksmuseet.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Zhang, Zhifei
    Brachiopod phylogeny revisited: Using stem groups to flesh out molecular tree topology2011Conference paper (Other academic)
  • 6.
    Bornsäter Mellbin, Barbro
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Linguliform brachiopods from the terminal Cambrian to lower Ordovician Tiñu section, Mexico2007In: 51st Palaeontological Association Annual Meeting: Programme with Abstracts, 2007, 64- p.Conference paper (Other academic)
    Abstract [en]
    The Tiñu Formation of Oaxaca State (Mexico) is the only fossiliferous lower Palaeozoic unit between the Laurentian platform in northwest Mexico and Gondwanan successions in Andean South America. It has recently been shown that the Tiñu section is a condensed passive margin succession with Gondwanan character. The formation is divided into two members, i.e., the uppermost Cambrian Yudachica Member, which rests nonconformably on middle Proterozoic basement, and the Lower Ordovician (Tremadoc) Río Salinas Member. The formation has been studied with respect to its depositional environments and its fossil content of trilobites and conodonts, which both provide excellent biostratigraphical control for the formation. Linguliform brachiopods of twelve limestone horizons of the Tiñu Formation have been studied. The fauna comprises about five acrotretid taxa, a new siphonotretid species and a few linguloid fragments. Detailed investigations on taxonomy and stratigraphic distribution of the taxa are currently in progress. An assessment of the changes in brachiopod associations across the Cambrian-Ordovician boundary and in relation to the described environmental changes occurring throughout the formation is one of the main points of the investigation.
  • 7.
    Butler, Aodhan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Bauert, Heikki
    NGO Geoguide Baltoscandia, Estonia.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Agić, Heda
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Recent palaeobiological and stratigraphical advances from the Cambrian of Estonia2011In: The 2nd Wiman Meeting: Carl Wiman's Legacy: 100 years of Swedish Palaeontology, Uppsala, 2011, 5-5 p.Conference paper (Refereed)
    Abstract [en]

    The unique Cambrian sediments of Estonia represent an important and understudied component of the Baltic system. Here we present an overview of recent field studies conducted by Uppsala University in association with colleagues from the Baltic Geotourism project, that have revealed a number of exciting discoveries in terms of Cambrian palaeontology and stratigraphy of Estonia. These include new purported stem lophotrochozoans with bizarre shell structure. Current efforts to describe and systematically appraise this material are outlined. The presence of unusual shell structure and whether this is the result of taphonomic alteration or indeed represents a novel shell structure type is examined. We propose herein affinities to the inarticulate stem-brachiopod Mickwitzia based upon the presence of an umbo and the overall gross morphology.  Possible new records of Estoniadiscus discinoides (Schmidt 1888), an extremely rare enigmatic organism with postulated affinities to eldonioids or other stem-group lophophorates are also described from the type section at Kakumägi, within the Kakumägi member Member of the lower Cambrian Tiskre formationFormation. The discovery of Dictyonema Rhabdinopora sp. graptolites, which have until now demarcated the Cambrian-Ordovician boundary, in-situ approximately 3 m below the previous reported occurrence from the Pakri cape section of the Kallavere formation Formation is also significant. Our findings highlight the need for both a stratigraphical and palaeobiological reapprasal of these important sequences, and their correlative implications for the Swedish and broader Baltoscandian regions.

  • 8.
    Butler, Aodhan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Garwood, Russel
    Manchester X-Ray Imaging Facility.
    Lowe, Tristan
    Manchester X-Ray Imaging Facility.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Constructing Cambrian body-plans: critical evaluation of tommotiid and stem-brachiopod character homologies2012Conference paper (Other academic)
  • 9.
    Butler, Aodhan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Babcock, Loren
    Lund University.
    Exceptional preservation of lower Cambrian mickwitziidsfrom the Indian Springs Lagerstätte, Nevada, and implications for early brachiopod phylogeny2011In: The Palaeontological Association, 55th Annual Meeting: Programme and Abstracts, 2011, 44-45 p.Conference paper (Refereed)
  • 10.
    Butler, Aodhan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Skovsted, Christian B.
    Naturhistoriska Riksmuseet.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Resolving the position of problematic lower to middle Cambrian lophotrochozoans: a critical appraisal of tommotiid and stem-brachiopod character homologies2012Conference paper (Other academic)
  • 11.
    Butler, Aodhán D.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Babcock, Loren
    Lund.
    Exceptionally-preserved Mickwitzia from the Indian Springs Lagerstätte.In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337Article in journal (Other academic)
    Abstract [en]

    A new assemblage of the early Cambrian stem group brachiopod Mickwitzia is described from the Indian Springs Lagerstätte possessing exceptionally preserved mantle setae. Critical analysis of shell structure and mantle setae from these specimens with those from additional sites with variable diagenetic history reveals the extent of taphonomic alteration and further sheds light on the phylogenetic position of the mickwitziids. A morphometric approach to shell outline and growth landmarks within these specimens reveals a clear species level discriminant signal of Nevada Mickwitzia in comparison to M. monlifera from Sweden. Detailed electron micrographs allow revision of the genus diagnosis for Mickwitzia based on presence of inward pointing phosphatic cones and tangential setae bearing tubes. We also conclude the inward pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent an endopunctae-like structure. A tommotiid-like shell architecture and presence of acrotretid columns in the dorsal juvenile shell of M. cf. occidens further strengthens the proposed close relationship between stem-group brachiopods and tommotiids.

  • 12.
    Butler, Aodhán D.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Babcock, Loren E.
    Exceptionally preserved Mickwitzia from the Indian Springs Lagerstätte (Cambrian Stage 3), Nevada2015In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 89, no 6, 933-955 p.Article in journal (Refereed)
    Abstract [en]

    ABSTRACT Exceptionally preserved specimens of the Cambrian stem-group brachiopod Mickwitzia occidens Walcott, 1908 are described in detail from the Indian Springs LagerstÀtte in Nevada, USA. Shell structure and preserved mantle setae from these specimens reveal a variable diagenetic (taphonomic) history and provide insight into the phylogenetic position of mickwitziids. Morphologic and morphometric comparison to M. monilifera (Linnarsson, 1869) from Sweden and M. muralensis Walcott, 1913 from British Columbia, Canada reveals clear species-level distinctions. Scanning electron microscopic analysis allows revision of the generic diagnosis. The Mickwitzia shell is characterized by the presence of inwardly pointing phosphatic cones and tangential setae-bearing tubes. The inwardly pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent endopunctae-like structures. Acrotretid-like shell structures and shell-penetrating setae in M. occidens strengthen the previously proposed close relationship between stem-group brachiopods and tommotiids, a group of small shelly fossils.

  • 13. Caron, Jean-Bernard
    et al.
    Gaines, Rober R.
    Mángano, Gabriella M.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Daley, Allison C.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new Burgess Shale-type assemblage from the "thin" Stephen Formation of the Southern Canadian Rockies2010In: Geology, ISSN 0091-7613, E-ISSN 1943-2682, Vol. 38, no 9, 811-814 p.Article in journal (Refereed)
    Abstract [en]

    A new Burgess Shale–type assemblage, from the Stephen Formation of the southern Canadian Rocky Mountains, is described herein. It occurs near Stanley Glacier in Kootenay National Park, 40 km southeast of the type area near Field, British Columbia. While at least a dozen Burgess Shale localities are known from the “thick” Stephen Formation, the Stanley Glacier locality represents the first discovery of Burgess Shale–type fossils from the “thin” Stephen Formation. The Cathedral Escarpment, an important regional paleotopographic feature, has been considered important to the paleoecologic set- ting and the preservation of the Burgess Shale biota. However, the Stanley Glacier assemblage was preserved in a distal ramp setting in a region where no evidence of an escarpment is present. The low- diversity assemblage contains eight new soft-bodied taxa, including the anomalocaridid Stanleycaris hirpex n. gen., n. sp. (new genus, new species). Pelagic or nektobenthic predators represent the most diverse group, whereas in relative abundance, the assemblage is dominated by typical Cambrian shelly benthic taxa. The low diversity of both the benthic taxa and the ichnofauna, which includes diminutive trace fossils associated with carapaces of soft-bodied arthropods, suggests a paleoenvironment with restrictive conditions. The Stanley Glacier assemblage expands the temporal and geographic range of the Burgess Shale biota in the southern Canadian Rockies, and suggests that Burgess Shale–type assemblages may be common in the “thin” Ste- phen Formation, which is regionally widespread.

  • 14.
    Caron, Jean-Bernard
    et al.
    Royal Ontario Museum, Toronto.
    Gaines, Robert
    Pamona College.
    Aria, Cédric
    Mangano, Gabriela
    University of Saskatchewan.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new phyllopod bed-like assemblage from the Burgess Shale of the Canadian Rockies2014In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 5, 3210- p.Article in journal (Refereed)
    Abstract [en]

    Burgess Shale-type fossil assemblages provide the best evidence of the ‘Cambrian explosion’. Here we report the discovery of an extraordinary new soft-bodied fauna from the Burgess Shale. Despite its proximity (ca. 40km) to Walcott’s original locality, the Marble Canyon fossil assemblage is distinct, and offers new insights into the initial diversification of metazoans, their early morphological disparity, and the geographic ranges and longevity of many Cambrian taxa. The arthropod-dominated assemblage is remarkable for its high density and diversity of soft-bodied fossils, as well as for its large proportion of new species (22% of total diversity) and for the preservation of hitherto unreported anatomical features, including in the chordate Metaspriggina and the arthropod Mollisonia. The presence of the stem arthropods Misszhouia and Primicaris, previously known only from the early Cambrian of China, suggests that the palaeogeographic ranges and longevity of Burgess Shale taxa may be underestimated.

  • 15.
    Caron, Jean-Bernard
    et al.
    Royal Ontario Museum, Toronto.
    Gaines, Robert
    Pamona College.
    Mangano, Gabriela
    University of Saskatchewan.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Discovery of a “phyllopod bed-like” fossil assemblage from Kootenay National Park2012Conference paper (Other academic)
  • 16.
    Freeman, Rebecca
    et al.
    Missouri State University.
    Miller, James
    Missouri State University.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Linguate brachiopod extinction and global migration coinciding with three laurentian trilobite extinction events during the late cambrian-earliest ordovician2011In: GSA Annual Meeting in Minneapolis, Minnesota USA, 2011, 543-543 p.Conference paper (Refereed)
    Abstract [en]

    Laurentian lingulate brachiopods on the outer shelf were affected by a series of three extinction events coinciding with trilobite extinctions (biomere boundaries). There was rapid turnover of the brachiopod faunas during each event. These extinctions are seen at the Steptoean/Sunwaptan, Sunwaptan/Skullrockian, and Skullrockian/Stairsian North American Upper Cambrian–lowest Ordovician stage boundaries. Lingulate brachiopods were examined from the Orr, Notch Peak, House, and Fillmore formations of western Utah and from the Catlin Formation and Hales Limestone of Nevada. Associated with each extinction event, brachiopod genera/species appeared that are also found in coeval strata in Kazakhstan and/or western Gondwana (e.g., Quadrisonia minorZhanatella rotunda, and species of Eurytreta). Some of these taxa may have appeared in the deeper water/higher latitude environments of Kazakhstan or Gondwana before appearing on the Laurentian shelf. Eurytreta may have appeared in deep-water slope environment at Tybo Canyon, Nevada before appearing in shelf environments in Utah.

    The Steptoean/Sunwaptan and Sunwaptan/Skullrockian boundaries were also examined in the Wilberns and Tanyard formations of central Texas. Latest Steptoean strata yield taxa widely distributed in Laurentia, although endemic to it, such as Linnarssonella girtyi. There is abrupt faunal change at the base of the Sunwaptan, followed by a fauna that is also endemic to Laurentia and is virtually identical to a fauna described from the Snowy Range Formation of Wyoming and Montana. This fauna is not present in coeval strata in Utah and Nevada. Mid-Sunwaptan strata in Texas yield a fauna with strong affinities to coeval strata in Utah; all species are endemic to Laurentia. The Sunwaptan/Skullrockian boundary is also characterized by complete turnover, this time with a replacement fauna having affinities both to the Laurentian outer shelf and to Gondwana and Kazakhstan.

    This pattern of events suggests that Late Cambrian–earliest Ordovician extinctions in Laurentia were caused by environmental changes that altered conditions on the Laurentian shelf to conditions more similar to those in deeper water (Kazakhstan) or higher latitudes (Gondwana), and these changes facilitated migration of globally distributed lingulate brachiopods.

  • 17. Geyer, Gerd
    et al.
    Hautmann, Michael
    Hagdorn, Hans
    Ockert, Willi
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    Well-preserved mollusks from the Lower Keuper (Ladinian) of Hohenlohe (Southwest Germany)2005In: Paläontologische Zeitschrift, ISSN 0031-0220, Vol. 79, no 4, 429-460 p.Article in journal (Refereed)
  • 18.
    Geyer, Gerd
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Peel, John Stuart
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Voigt, Sebastian
    Fischer, Jan
    Preusse, Marvin
    A remarkable Amgan (Middle Cambrian, Stage 5) fauna from the Sauk Tanga, Madygen region, Kyrgyzstan2014In: Bulletin of Geosciences, ISSN 1214-1119, E-ISSN 1802-8225, Vol. 89, no 2, 375-400 p.Article in journal (Refereed)
    Abstract [en]

    Early Middle Cambrian bituminous coquinoid limestones from a tectonically isolated outcrop in southwestern Kyrgyzstan yield a remarkably diverse fauna, with stem-group cnidarians, trilobites, rhynchonelliformean brachiopods, and other shelly fossils. The fossil site is in the northern foothills of the Turkestan Range and thus forms part of the westernmost extension of the South Tien Shan. The fauna includes two fairly well known trilobite species, Glabrella ventrosa Lermontova, 1940 and Dorypyge richthofeniformis Lermontova, 1940, that provide confident support for an Amgan age of the rocks. New described taxa include the stem-group cnidarian Cambroctoconus kyrgyzstanicus Peel sp. nov., the trilobite Olenoides sagittatus Geyer sp. nov., and the helcionelloid Manasoconus bifrons Peel gen. et sp. nov. Additional fossils within the samples include the trilobites Olenoides sp. A, Kootenia sp., and Pseudoeteraspis? sp.; the rhynchonelliform brachiopods Narynella cf. ferganensis (Andreeva, 1962), Narynella? sp., Austrohedra? sp. nov., and two species of uncertain generic affinity; the tommotiid Tesella sp.; the hyolithelminth Hyolithellus sp.; and the palaeoscolecid Hadimopanella oezgueli Gedik, 1977. Of particular interest is Cambroctoconus kyrgyzstanicus with an octagonal corallum and a sparsely septate calyx.

  • 19. Hildebrand-Habel, Tania
    et al.
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    Calcareous dinoflagellate associations and Maastrichtian-Tertiary climatic change in a high-latitude core (ODP Hole 689B, Maud Rise, Weddell Sea)2003In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, Vol. 197, 293-321 p.Article in journal (Refereed)
    Abstract [en]

    The distribution of calcareous dinoflagellates has been analysed for the Maastrichtian to Miocene interval of ODP Hole 689B (Maud Rise, Weddell Sea). The investigation thus represents a primary evaluation of the long-term evolution in high latitude calcareous dinoflagellate assemblages during the transition from a relatively warm Late Cretaceous to a cold Neogene climate. Major assemblage changes during this interval occurred in characteristic steps: (1) an increase in relative abundance of tangentially structured species – particularly Operculodinella operculata – at the K/T boundary; (2) a diversity decrease and several first and last appearances across the middle–late Eocene boundary, possibly attributed to increased climate cooling; (3) a diversity decrease associated with the dominance of Calciodinellum levantinum in the late early Oligocene; (4) the reappearance and dominance of Pirumella edgarii in the early Miocene, probably reflecting a warming trend; (5) monogeneric assemblages dominated by Caracomia spp. denoting strong middle Miocene cooling. The results not only extend the biogeographic ranges of many taxa into the Antarctic region, but also indicate that the evolution of high latitude calcareous dinoflagellate assemblages parallels the changing environmental conditions in the course of the Cenozoic climate transition. Therefore, calcareous dinoflagellates contribute to our understanding of the biotic effects associated with palaeoenvironmental changes and might possess the potential for reconstructing past conditions. The flora in the core includes one new taxon: Caracomia arctica forma spinosa Hildebrand-Habel and Streng, forma nov. Additionally, two new combinations are proposed: Fuettererella deflandrei (Kamptner, 1956) Hildebrand-Habel and Streng, comb. nov. and Fuettererella flora (Fütterer, 1990) Hildebrand-Habel and Streng, comb. nov.

  • 20. Hildebrand-Habel, Tania
    et al.
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    Long-term changes vs. short-term changes in calcareous dinoflagellates - examples from the Tertiary.2004Conference paper (Other scientific)
  • 21.
    Holmer, Lars E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid E.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Miller, James F.
    Lower Ordovician (Tremadocian) lingulate brachiopods from the House and Fillmore formations, Ibex Area, western Utah, USA2005In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 79, no 5, 884-906 p.Article in journal (Refereed)
    Abstract [en]

    Seven genera and eight species of lingulate brachiopods were recovered from the House Limestone and lower Fillmore Formation, Ibex area, Utah, USA. These strata are assigned to the upper Skullrockian Stage and lower Stairsian Stage of the Ibexian Series (Iapetognathus Conodont Zone to Low Diversity Interval) and are correlated with the Tremadocian Series of the Acado–Baltic Faunal Province. The fauna includes two new linguloid species, Spinilingula prisca and Wahwahlingula sevierensis, one new siphonotretoid species, Schizambon obtusus, and two new acrotretoid species, Eurytreta fillmorensis and Ottenbyella ibexiana. The last species is the first record of the genus in North America and suggests a correlation of the basal Fillmore Formation with the Ceratopyge Limestone in Sweden. A Siphonobolus? covered by long hollow spines may be one of the oldest siphonotretides with such ornament. This fauna and those described previously from older Utah strata document the biodiversification of the Cambrian–Ordovician lingulate brachiopods and demonstrate their potential for regional and intercontinental correlation.

  • 22.
    Holmer, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, L. E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Organophosphatic stem group brachiopods: implications for the phylogeny of the subphylum Linguliformea2008In: Brachiopoda: fossil and recent / [ed] Harper, David A, Chichester: Wiley-Blackwell , 2008, Vol. 54, 3-11- p.Chapter in book (Other academic)
  • 23.
    Holmer, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid E.
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Organophosphatic stem group brachiopods - implications for the phylogeny of the Subphylum Linguliformea2005In: Proceedings of the 5th International Brachiopod Congress, Copenhagen, 2005, 17- p.Conference paper (Other scientific)
  • 24.
    Holmer, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Palaeobiology.
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Palaeobiology.
    Skovsted, Christian
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Palaeobiology.
    Babcock, Loren E.
    Exceptional preservation in the stem group brachiopod Mickwitzia from the Early Cambrian of Nevada2004Conference paper (Other scientific)
  • 25.
    Kear, Benjamin P.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Carl Wiman's legacy: 100 years of Swedish palaeontology2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, 1-2 p.Article in journal (Other academic)
  • 26.
    Kear, Benjamin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, MichaelUppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The 2nd Wiman meeting: Carl Wiman's Legacy: 100 years of Swedish Palaeontology2011Conference proceedings (editor) (Refereed)
  • 27.
    Kear, Benjamin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, MichaelUppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The 2nd Wiman Meeting: Carl Wiman's Legacy: 100 years of Swedish Palaeontology2011Conference proceedings (editor) (Refereed)
  • 28.
    Mangano, Gabriela
    et al.
    University of Saskatchewan.
    Caron, Jean-Bernard
    Royal Ontario Museum, Toronto.
    Gaines, Robert
    Pamona College.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The paradox of exceptional trace-fossil assemblages in Cambrian unstable settings2012Conference paper (Other academic)
  • 29.
    Peel, John Stuart
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new middle Cambrian bradoriid arthropod from Greenland and western Canada2015In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 89, no 1, 96-102 p.Article in journal (Refereed)
    Abstract [en]

    Circum-Laurentian middle Cambrian (Cambrian Series 3) deposits in Greenland and British Columbia yield a new hipponicharionid bradoriid arthropod, Flumenoglacies n. gen., characterized by a comarginal, ramp-like structure which is crested by a continuous lobe. The narrow lobe is the result of the medial fusion of anterior and posterior lobes, seemingly a recurrent theme in hipponicharionid evolution. The type species, F. groenlandica n. sp., is described from the Ekspedition Brae Formation (Drumian Stage) of Peary Land but the description of two unnamed species from slightly older middle Cambrian strata of the Stephen Formation of British Columbia provides additional evidence for the wide distribution of Small Shelly Faunas during the Cambrian.

  • 30.
    Skovsted, Christian
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Knight, I.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Setatella significans, a new name for mickwitziid stem group brachiopods from the lower Cambrian of Greenland and Labrador2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 2, 117-122 p.Article in journal (Refereed)
    Abstract [en]

    Setatella significans gen. et sp. nov. from the Lower Cambrian of North-East Greenland, originally described under the name ‘Mickwitzia cf. occidens’, is introduced as a probable stem group brachiopod. Newly collected specimens of Setatella significans from the Forteau Formation of southern Labrador exhibit new morphological details and provide a better understanding of its ontogeny. Setatella significans differs from species of Mickwitzia in having a ventral pseudointerarea and hemiperipheral growth in both valves. Setatella significans probably belongs to the derived stem group of the Linguliformea that can be differentiated from the more primitive Mickwitzia. The geographic range of Setatella is extended to southern Labrador.

  • 31.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Emiliania Sánchez, 1999 is not a homonym of Emiliania Hay and Mohler, 19672010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 84, no 6, 1226-1226 p.Article in journal (Other academic)
  • 32.
    Streng, Michael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Malformation and functional morphology as a clue to pedicle size and pedicle morphology of ceratretid brachiopods (Acrotretida; Linguliformea)2007In: 51st Palaeontological Association Annual Meeting: Programme with Abstracts, 2007, 96- p.Conference paper (Other scientific)
    Abstract [en]

    Evidence for pedicle sizes and pedicle morphologies of fossil linguliform brachiopods is scarce and mainly restricted to exceptionally preserved specimens of fossil Lagerstätten. Recently described specimens of linguloid brachiopods with preserved soft parts have shown that the traditional view of these brachiopods being infaunal and bearing a long pedicle was incorrect, and there existed a wider range of pedicle morphologies and lifestyles. Not all linguloid brachiopods had a burrowing life style, and epibenthic forms with either long thread-like or short and robust pedicles also existed. Despite this variety of pedicles in linguloid brachiopods, virtually nothing is known about pedicle morphology of acrotretid brachiopods, an extremely diverse and common group during the early Palaeozoic. Evidence from a malformed shell of the middle Cambrian Acanthatreta suggests that some acrotretids, i.e., the family Ceratretidae, had a short, pad-like pedicle that permanently attached to a hard substrate. The posterior margin of the malformed shell shows two dents symmetrically arranged adjacent to the pseudointerarea. These dents may have formed because the brachiopod larva had settled in a shallow depression on the seafloor, which imposed lateral growth limitations on the brachiopod shell during the juvenile growth state. As these lateral limitations could not be actively compensated for by the organism, a firm attachment with a short pedicle is assumed. This is in accordance with the funnel shaped external pedicle opening of Acanthatreta, which tapers towards the interior of the shells and probably hosted the main part of the pedicle. This type of opening allows the pedicle to expand rapidly in diameter towards the exterior, thereby enlarging the attachment area and facilitating a firm connection to the substrate.

  • 33.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The nature of fake predation traces in the Cambrian – implications for the early record of macrophagy2012Conference paper (Other academic)
    Abstract [en]

    Boreholes in mineralized shells are a widely recognized form of predation throughout the Phanerozoic. In fact, such borings are as old as the first mineralized shells dating back to the Ediacaran. Their occurrence among the earliest skeletal animals has been interpreted that protection against predators was one of the driving forces behind the evolution of mineralized hardparts. Hence, these early traces provide crucial clues in understanding the mysterious emergence of complex multicellular animals. However, new observations made on shells of linguliform brachiopods from the Cambrian of Sweden suggest caution when interpreting perforations in shells as predatory or even as being organic. The recovered acrotretid assemblage is characterized by an unusual frequency of shells bearing circular to irregular circular holes. These holes resemble shell perforations interpreted in the literature as predatory borings and holes produced by a predator using a piercing appendage. However, close examination of the shells reveals the presence of pyrite crystals growing on the shell surfaces and within shell layers, thereby destroying the shell and producing the common perforations. It is proposed that pyrite crystal growth might be responsible for a variety of holes in fossil shells, holes previously interpreted to be predatory. 

  • 34.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    Babcock, Loren E.
    Hollingsworth, J. Stewart
    Agglutinated protists from the Lower Cambrian of Nevada2005In: Journal of Paleontology, ISSN 0022-3360, Vol. 79, no 6, 1214-1218 p.Article in journal (Refereed)
  • 35.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Banasová, Mariana
    Comenius University Bratislava.
    Rehaková, Daniela
    Comenius University Bratislava.
    Willems, Helmut
    Universität Bremen.
    An exceptional flora of calcareous dinoflagellates from the middle Miocene of the Vienna Basin, SW Slovakia2009In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 153, 225-244 p.Article in journal (Refereed)
    Abstract [en]

    Novel and diverse associations of calcareous dinoflagellate cysts have been discovered in Late Badenian (late Middle Miocene) coastal marine sediments within the Vienna Basin. Samples derive from a clay pit near Devínska Nová Ves, a borough of Bratislava, Slovakia, in which the Late Badenian lectotype section is exposed. Seventeen different taxa, many of them new and of abnormal morphology, have been distinguished and assigned to ten genera. The following seven taxa are newly introduced from the Devínska Nová Ves clay pit: four genera comprising five new species, i.e., Calciconus irregularis, Juergenella remanei, Cylindratus borzae, Posoniella pustulata, Posoniella campestris, one new varietas, i.e., Calcicarpinum perfectum var. poratum, and one new forma, i.e., Caracomia arctica forma duplicata. In addition, the following new combinations have been made: Posoniella tricarinelloides (Versteegh), Juergenella ansata (Hildebrand-Habel and Willems), and Juergenella granulata (Kohring). The genus Melodomuncula Versteegh is emended based on a new interpretation of its tabulation, and the genus Pirumella Bolli is emended because the concept used for the genus is not in accordance with the original description.

  • 36.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Butler, Aodhán D.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Garwood, Russell J.
    The University of Manchester, School of Earth Atmospheric and Environmental Sciences.
    Caron, Jean-Bernard
    Department of Ecology and Evolutionary Biology, University of Toronto.
    A new family of Cambrian rhynchonelliformean brachiopods (Order Naukatida) with an aberrant coral-like morphology2016In: Palaeontology, ISSN 0031-0239, E-ISSN 1475-4983, Vol. 59, no 2, 269-293 p.Article in journal (Refereed)
    Abstract [en]

    Tomteluva perturbata gen. et sp. nov. and Nasakia thulensis gen. et sp. nov., two new rhynchonelliformean brachiopod taxa, are described from carbonate beds from the lower middle Cambrian (Series 3, Stage 5) basinal Stephen Formation, Canada, and the upper lower Cambrian (Series 2, Stage 4) Henson Gletscher Formation, North Greenland, respectively. The two taxa are characterized by an unusual coral-like morphology typified by a high conical ventral valve with an anteriorly curved umbo and a tube-like structure inside the ventral valve, interpreted as pedicle tube. Both resemble the problematic late middle Cambrian (Drumian) species Anomalocalyx cawoodi Brock from Australia, whose systematic affiliation is controversial. Together, the three genera are interpreted as representatives of a new family of rhynchonelliformean brachiopods, the Tomteluvidae fam. nov., which is interpreted as an aberrant or derived taxon within the Order Naukatida. Convergence between the Tomteluvidae and the coralla of small solitary Cambrian coralimorphs, as well as the late Palaeozoic reef-building richthofenioid brachiopods, might indicate adaptation to a similar life habits and environments. However, their small size (length 4 mm), well-developed pedicle and perfect morphological symmetry make it more likely that tomteluvids lived attached to frondose algae or sponges, above the seafloor, in a similar fashion to the acrotretoid brachiopods with which they show a high degree of morphological convergence. Morphological features of the pedicle tube of N. thulensis suggest that the tomteluvid pedicle is homologous to that in modern rhynchonelliformean brachiopods. This is the first evidence of the pedicle type within the Naukatida and represents the oldest confirmation of a rhynchonellate pedicle.

  • 37.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Museums etc., Museum of Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    New palaeoscolecids from the Cambrian of Scandinavia2007In: Lundadagarna i historisk geologi och paleontologi X: 12-13 March 2007 Abstracts with programme, 2007, 44- p.Conference paper (Other scientific)
    Abstract [en]

    Palaeoscolecid sclerites were found in samples originating from three lower Middle Cambrian localities of southern Scandinavia: Brantevik, Scania [Forsemölla Limestone Bed (= 'fragment' limestone)]; Bornholm (Exulans Limestone Bed); and Öland (Granulata Conglomerate Bed). Four morphotypes are distinguished which are assigned to three new species, here informally named Hadimopanella sp. A, sp. B and sp. C. Hadimopanella sp. A includes two morphotypes typified by the end members of a continuous morphological series: both morphotypes have a central elevated platform, which is characterized by several larger knobs circumscribing the platform in the first, and by numerous small knobs covering the hole platform in the second morphotype. All specimens from Scandinavia which have been previously illustrated and informally named Hadimopanella sp. belong to this taxon. Hadimopanella sp. B resembles Hadimopanella sp. A, but does not show its wide variety and has a convex platform surface rather than a concave one. Hadimopanella sp. C bears a central spiny knob which is surrounded by six to 14 similar shaped and sized knobs. The central knob might be split into a cluster of up to six smaller pointy knobs. The study demonstrates vividly the importance of having a large number of sclerites to accurately assess the morphological range realized within the scleritome of a palaeoscolecid species that is known only in disarticulated form. Thus, without knowing the morphological range, individual sclerites of Hadimopanella sp. A could easily be mistaken for two species. Likewise, individual sclerites of Hadimopanella sp. C could be misidentified as Sahascolex labyrinthus Ivantsov & Wrona from the Lower Cambrian of Siberia. In addition to the disarticulated sclerites, two palaeoscolecid cuticle remains from the Lower Cambrian Skyberg Member (Ringstrand Formation) of Norway are presented. The remains show the typical body annulations of palaeoscolecids but the poor preservation of the individual sclerites does not allow a detailed systematic allocation.

  • 38.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Esper, Oliver
    Alfred Wegener Institute, Bremerhaven.
    Wollenburg, Jutta
    Calcareous dinoflagellate cysts from the Pleistocene (Marine Isotope Stage 31) of the Ross Sea, Antarctica2011In: Antarctic Science, ISSN 0954-1020, E-ISSN 1365-2079, Vol. 23, no 6, 597-604 p.Article in journal (Refereed)
    Abstract [en]

    Following a report of supposed fragments of calcareous dinoflagellate cysts from a Pleistocene drill core (CRP-1) recovered in the Ross Sea, Antarctica, sediments of the same core were re-investigated for their microfossil content. Besides common foraminifera and other microfossils, rare complete cysts of calcareous dinoflagellates were found. All cysts belong to the species Caracomia arctica (Gilbert & Clark, 1983) Streng, Hildebrand-Habel & Willems, 2002, a taxon characteristic of late Neogene high latitude, coldwater environments. Two morphotypes can be distinguished, C. arctica f. arctica and C. arctica f. rossensis, of which the latter is described as a new form. The presence of C. arctica strengthens diatom-based palaeoenvironmental reconstructions of periodical sea ice-free conditions at the time of deposition. Accordingly, cysts of C. arctica are interpreted as resting cysts that allow survival during harsh intervals of the high latitude environment. Previously reported calcareous dinoflagellates cyst fragments from these sediments are re-interpreted as test fragments of bilamellar foraminifera, which represent the most common group of foraminifers in the sediments.

  • 39.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Gaines, Robert
    Pamona College.
    Caron, Jean Bernard
    Royal Ontario Museum Toronto.
    Palaeontology and stratigraphy of the middle Cambrian Stephen Formation, western Canadian Rocky Mountains2011In: The 2nd Wiman Meeting: Carl Wiman's Legacy: 100 years of Swedish Palaeontology, Uppsala, 2011, 22-22 p.Conference paper (Refereed)
    Abstract [en]

    The middle Cambrian Stephen Formation of the western Canadian Rocky Mountains might be best known for including the famous Burgess Shale with its exceptionally preserved fossils. Likewise remarkable is, however, its depositional setting, which was characterized by the presence of a submarine cliff that divided the environment into a deeper, basinal and a shallower part. This division, caused by the so called Cathedral Escarpment, resulted in the development of two distinct regional expressions of the formation, a thick, i.e., basinal, and a thin, i.e., shallower, one. Whereas previous paleontological studies of the Stephen Formation mainly focused on the exceptional preserved fauna and its macroscopic fossils, we present here the first systematic study of the microfossil content of the limestone horizons occurring throughout the formation. Five sections of the thin and thick Stephen Formation have been measured and sampled in Yoho and Kootenay National Park. In total, samples from over 130 horizons have been dissolved in diluted formic acid revealing a variable fauna of dominantly phosphatic shelled brachiopods (mainly Acrothyra and Paterina, but also lingulids and zhanatellids) and trilobites (mainly ptychoparids and Pagetia; other trilobites and agnostids are rare). Locally recrystallized echinoderm ossicles, which can be referred to ctenocystoids and edrioasteroids, and a variety of siliceous sponge spicules are common. Molluscs, such as helcionellids, stenothecoids, or hyoliths, are present, but typically form only an insignificant part of the associations. Bradoriids as well as protoconodonts are rare and have only been found in individual horizons. The evaluation of the distribution of the fauna in the individual sections aims towards a detailed correlation of the sections, a more exhaustive biostratigraphy, and a better understanding of the regional variability of the formation.

  • 40.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Geyer, Gerd
    Budd, Graham
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A bone bed without bones: the Middle Cambrian 'fragment limestone' of Scania, Sweden2006Conference paper (Refereed)
    Abstract [en]

    The Middle Cambrian 'fragment limestone' of southeastern Scania (S. Sweden) is a greenish-gray wacke- to packstone layer that varies in thickness from 2 to 20 cm, overlying the Gislöv Formation (sensu stricto) with an erosive contact. It is extremely rich and diverse in small phosphatic-shelled fossils: 16 different taxa have been identified thus far, among which the phosphatic shelled brachiopods are the most common (seven taxa). Other faunal elements are paraconodonts (two taxa), palaeoscolecids (two taxa), phosphatocopids (at least two taxa), Microdyction sp., Lapworthella sp., and Hyolithellus sp., and undeterminable trilobite hash. Petrographic features of the fragment limestone such as phosphorite nodules, pyrite and authigenic glauconite, scattered quartz grains, the high content of phosphatic-shelled organisms, as well as signs of stratigraphic mixture (reworking), presence of intraclasts, and an erosive sole indicate a genesis similar to classical bone beds such as the Muschelkalk Grenzbonebed of South Germany. The fragment limestone is considered here to be a condensation deposit (Konzentratlagerstätte) in which phosphatic-shelled organisms have been enriched by long-term sedimentary reworking and winnowing of finer material.

  • 41.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Hildebrand-Habel, Tania
    Meier, Sebastian
    Fensome, Robert
    Clarification of the systematic position of two calcareous dinoflagellate taxa belonging to the genus Calciodinellum (Dinophyceae, Peridiniales)2006In: Micropaleontology, ISSN 0026-2803, Vol. 52, no 2, 189-192 p.Article in journal (Refereed)
  • 42.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    Hildebrand-Habel, Tania
    Willems, Helmut
    A proposed classification of archeopyle types in calcareous dinoflagellate cysts2004In: Journal of Paleontology, ISSN 0022-3360, Vol. 78, no 3, 456-483 p.Article in journal (Refereed)
    Abstract [en]

    The phylogenetic significance of archeopyles in calcareous dinoflagellates cysts has been evaluated, and a classification model is developed that focuses on the archeopyle categories and types established for organic-walled dinoflagellates by Evitt (1967, 1985). Several of Evitt's archeopyle categories are presently recognized within the calcareous dinoflagellate cysts: apical, intercalary, and combination archeopyles, which are here subdivided into eight archeopyle types and several variations. Archeopyles that cannot be assigned to a distinct type, and those with outlines that do not allow an accurate interpretation, are together placed in a separate category: miscellaneous archeopyles. The stratigraphic distribution of the different archeopyle types reveals a phylogenetic trend characterized by an increase of the number of plates involved in archeopyle formation. The first calcareous dinoflagellate cysts to appear in the late Triassic, have a monoplacoid apical archeopyle. The first taxa that show an archeopyle involving more than one plate are from the Early Cretaceous, with the first triplacoid apical archeopyle appearing at the Berriasian/Valanginian boundary. This is followed by the first combination archeopyles, which includes six plates, in the middle Aptian. Epitractal archeopyles originated no earlier than the early Oligocene. At the beginning of the Paleogene, species with a combination archeopyle increased in abundance progressively replacing species possessing an apical archeopyle that dominated during the Mesozoic. Newly described species are: Calciodinellum clamosum, accommodating the two subspecies Calciodinellum clamosum subsp. clamosum Autonym, and Calciodinellum clamosum subsp. latum; Calciodinellum kerguelense; Fuettererella belliata; and Pernambugia? patata. New combinations are: Cervisiella operculata (Bramlette and Martini, 1964); Praecalcigonellum sulcatum (Keupp, 1979a); and Praecalcigonellum dolium (Keupp, 1979b). Because of the new interpretation of their archeopyles we emend the following genera: Cervisiella Hildebrand-Habel, Willems and Versteegh, 1999, Echinodinella Keupp, 1980; Fuettererella Kohring, 1993a; and Pernambugia Janofske and Karwath in Karwath (2000). The species Orthopithonella? minuta and Pirumella johnstonei, which have been previously synonymized with Fuettererella deflandrei, are retained as independent taxa.

  • 43.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology. Paleobiologi.
    Hildebrand-Habel, Tania
    Willems, Helmut
    Long-term evolution of calcareous dinoflagellate associations since the Late Cretaceous: comparison of a high- and a low-latitude core from the Indian Ocean.2004In: Journal of Nannoplankton Research, ISSN 1210-8049, Vol. 26, no 1, 13-45 p.Article in journal (Refereed)
    Abstract [en]

    A high and a low latitude Ocean Drilling Program core from the southern and eastern Indian Ocean, respectively, were studied to obtain a general overview of the evolution of calcareous dinoflagellate cyst associations in this region and their possible reaction to known major Cenozoic climatic changes. Despite a relatively low sample density, several shifts in calcareous dinoflagellate assemblages could be linked to periods of major climatic or environmental changes at the Cretaceous/Tertiary transition, in the early Oligocene, and in the Neogene. Correlations between changes in the climate and in the associations appear to be more distinctive at high latitudes than at low latitudes. For the first time, shifts in the stratigraphic distribution pattern of different archaeopyle types have been evaluated. The ratio between small and large archaeopyles turned out to be a possible tool for the reconstruction of long-term climatic evolution at high latitudes, with small archaeopyles correlating with warmer periods and large archaeopyles characterising cooler conditions. Altogether, 65 taxa have been distinguished of which several rare or problematic taxa, which may partly represent new species, are informally described or described using open nomenclature. Additionally, the relationship and potential synonymy of the problematic species Thoracosphaera? prolata with Calciodinellum elongatum is discussed in detail.

  • 44.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    New and poorly known acrotretid brachiopods (Class Lingulata) from the Cedaria-Crepicephalus zone (late Middle Cambrian) of the Great Basin, USA2006In: Geobios, ISSN 0016-6995, E-ISSN 1777-5728, Vol. 39, no 1, 125-154 p.Article in journal (Refereed)
    Abstract [en]

    Seven new late Middle Cambrian (Cedaria-Crepicephalus zone) acrotretid species are described from the Great Basin, USA. The species belong to five genera of which Lensotreta is new. The following new species are described: Anabolotreta? glabra, Anabolotreta mogota, Canthylotreta crista, Dactylotreta elegantula, Lensotreta perplexa, Opisthotreta transversa, and Opisthotreta indistincta. The shell structure of Canthylotreta is described for the first time based on new material of the type species Canthylotreta marjumensis and of the new species C. crista. The shell of Canthylotreta includes two types of shell fabric, camerate and columnar. Moreover, parts of the shell show transitional textures, supporting the view that the camerate shell structure may has originated from a columnar fabric. Picnotreta lophocracenta Robson and Pratt, 2001, recently described from western Newfoundland, is also described from the new occurrence in the Great Basin.

  • 45.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences.
    Holmer, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences.
    Shell structure evolution of Cambrian organophosphatic brachiopods2005In: Lundadagarna i Historisk Geologi och Paleontologi, 2005, 57- p.Conference paper (Other scientific)
  • 46.
    Streng, Michael
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Weird, weirder, Mickwitzia - the odd features of a stemgroup brachiopod and their implications for brachiopod phylogeny.2005In: Proceedings of the 5th International Brachiopod Congress, Copenhagen, 2005, 28-29 p.Conference paper (Other scientific)
  • 47.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Discovery of a new type of shell structure within the organophosphatic brachiopods and the status of the family Curticiidae2005In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 127, 7-16 p.Article in journal (Refereed)
    Abstract [en]

    AbstractA new representative of the family Curticiidae, Curticia? pattersonensis (Class Lingulata, Brachiopoda), is described from the upper Middle Cambrian (Cedaria-Crepicephalus zone) of the Great Basin, USA. It displays a new type of shell structure which is characterized by a baculate secondary and a columnar tertiary layer, a combination previously unreported within the organophosphatic brachiopods. Examinations of the surface of the larval shell of Curticia? pattersonensis sp. nov. revealed in addition an previously unreported ornamentation typified by hemispherical pits of uniform size that exceed the larval shell by a certain distance. This is in strong contrast to the pits of Curticia minuta which are variable in size and restricted to the larval shell questioning the co-generic position of the new taxon. The formation of the pedicle opening by means of resorption of the shell from a juvenile foramen to a adult delthyrium known from Curticia minuta and supposed to be characteristic for the whole family could not be confirmed by observations on the ontogeny of Curticia? pattersonensis sp. nov. In fact a broad triangular delthyrium seems to be present in all growth stages of the new taxon. The observations on the shell structure and ontogeny of C.? pattersonensis sp. nov. indicate that the present systematic position of the Curticiidae within the superfamily Acrotretoidea and the current definition of the family need to be re-considered.

  • 48.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid E.
    Department of Geology, National Museum of Wales.
    Budd, Graham E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Columnar shell structures in early linguloid brachiopods: new data from the Middle Cambrian of Sweden2008In: Earth and Environmental Science Transactions of the Royal Society of Edinburgh, ISSN 1755-6910, Vol. 98, no Part 3-4, 221-232 p.Article in journal (Refereed)
    Abstract [en]

    The records of columnar shell structures of linguloid brachiopods (Class Lingulata, Order Lingulida, Superfamily Linguloidea) are reviewed in the light of the discovery of two new taxa from the Middle Cambrian Forsemölla Limestone Bed of southern Sweden. The linguloid taxa, described here as Eoobolus? sp. aff. E. priscus (Poulsen) and Canalilatus? simplex sp. nov., are both characterised by a columnar shell structure, a structural type that is representative for acrotretoid brachiopods and that has previously only rarely been reported from the linguloids. Though the two taxa are superficially similar to known genera, i.e., Eoobolus and Canalilatus, their shell structure challenges such affiliations, as the shell structure of the type species of these genera is previously unknown. Linguloid families whose morphological characteristics agree the most with those of the new taxa, i.e., the Zhanatellidae and the Eoobolidae, and from which columnar shell structures have been reported, i.e., the Lingulellotretidae and the Kyrshabaktellidae, are reviewed briefly. Many taxa assigned to these families completely lack shell structure data and are in need of restudy in order to elucidate their systematic position. Knowledge of the representative type of shell structure of the various suprageneric taxa within the Linguloidea is considered crucial, in order to unravel their currently poorly resolved phylogenetic relationships.

  • 49.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Mellbin, Barbro B.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Landing, Ed
    Keppie, J. Duncan
    Linguliform brachiopods from the terminal Cambrian and lowest Ordovician of the Oaxaquia microcontinent (Southern Mexico)2011In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 85, no 1, 122-155 p.Article in journal (Refereed)
    Abstract [en]

    Eighteen taxa of linguliform brachiopods, mainly represented by acrotretoids, are reported from the Upper Cambrian (Furongian, Stage 10) and Lower Ordovician (Tremadocian) Tinu Formation of Oaxaca State, Mexico. At the time of deposition, this area was part of Oaxaquia, which was either a microcontinent or an integral part of the Gondwanan margin. Whereas certain trilobites seem to indicate a Gondwanan affinity, the Tinu brachiopod faunas show a less definite paleogeographic relationship. Some taxa have previously only been reported from Laurentia (Eurytreta cf. fillmorensis, Eurytreta cf. campaniformis), and one taxon is best known from the Avalon microcontinent (Eurytreta cf. sabrinae). However, the relatively high percentage of new and potentially endemic taxa (Oaxaquiatreta labrifera n. gen. n. sp., Tapuritreta reclinata n. sp., Oaxaquiatreta sp., Eurytreta? n. sp., Acrotretidae n. gen. n. sp., Obolinae gen. and sp. indet.) and the lack of other typical Laurentian, Gondwanan, or Avalonian taxa suggest either a certain degree of insularity of Oaxaquia or reflects a more temperate, unrestricted marine environment during the Early Paleozoic. Other taxa reported from the Tinu Formation include Semitreta sp., Lingulella? spp., Obolinae gen. and sp. indet., Eoscaphelasma? sp., Ottenbyella? sp. A and sp. B, and Acrotretidae gen. and sp. indet. A, B, and C. Eurytreta and Semitreta are critically reviewed and several taxa previously assigned to them have been excluded. An emended diagnosis for the genus Eurytreta is presented. The presence of delthyrium and notothyrium-like structures in the siphonotretid Oaxaquiatreta n. gen. further strengthens the previously proposed relationship between the Siphonotretida and Paterinida.

  • 50.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Skovsted, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new mobergellan (small shelly fossils) from the Middle Cambrian of Morocco and its significance2006In: Paläontologische Zeitschrift, ISSN 0031-0220, Vol. 80, no 3, 209-220 p.Article in journal (Refereed)
    Abstract [en]

    A new mobergellan genus and species, Tateltella ranoculata, is described from the early Middle Cambrian (Agdzian Stage) of Morocco. The new taxon is characterized by only four pairs of muscle scars and is furthermore distinguished from other mobergellans by its strongly concave shape and its distally rising muscle scars. The individual specimens of Tateltella ranoculata distinctly vary in size and display different ontogenetic stages. Juvenile, intermediate, and adult stages can be distinguished by means of the development of the muscle scars that differ in position relative to the apex, size, and distinctness between individual stages. The shell of T. ranoculata is composed of a succession of thin phosphatic lamellae separated by interlamellar gaps, presumably originally filled by organic material. The interlamellar gaps may be divided by septum-like structures producing discrete cavities. The specimens are the youngest mobergellans known so far and correlation of their stratigraphic position suggests a correspondence with the lower part of the Amgan stage of the Siberian Platform. In addition, they are the first reported mobergellans from the present day continent Africa. Other mobergellan taxa and mobergellan-like species are briefly reviewed and the genus Hippoklosma MISSARZHEVSKY, previously assigned to the Mobergellidae, is excluded from the family due to its different shell structure. An evolutionary trend of reduction in the number of muscle scars from 14 in the early Early Cambrian to only eight in the early Middle Cambrian is apparent among mobergellans.

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