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  • 2051.
    Winnberg, Ulrika
    et al.
    Stockholms universitet.
    Rydén, Andreas
    Stockholms universitet.
    Löfstrand, Karin
    Stockholms universitet.
    Asplund, Lillemor
    Stockholms universitet.
    Bignert, Anders
    Swedish Museum of Natural History, Department of.
    Marsh, Göran
    Stockholms universitet.
    Novel Octabrominated Phenolic Diphenyl Ether Identified in Blue Mussels from the Swedish West Coast2014In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, p. 3319-3326Article in journal (Refereed)
  • 2052.
    Winton, V.H.L.
    et al.
    Curtin University, Perth.
    Dunbar, G.B.
    Antarctic Research Centre, Wellington.
    Atkins, C.B.
    Victoria University, Wellington.
    Bertler, N.A.N.
    Antarctic Research Centre, Wellington.
    Delmonte, Barbara
    University of Milano-Bicocca, Milano.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    Bowie, A
    University of Tasmania, Hobart.
    Edwards, R.
    Curtin University, Perth.
    The origin of lithogenic sediment in the south-western Ross Sea and implications for iron fertilization2016In: Antarctic Science, ISSN 0954-1020, E-ISSN 1365-2079, Vol. 28, no 4, p. 250-260Article in journal (Refereed)
    Abstract [en]

    Summer iron (Fe) fertilization in the Ross Sea has previously been observed in association with diatom productivity, lithogenic particles and excess Fe in the water column. This productivity event occurred during an early breakout of sea ice via katabatic winds, suggesting that aeolian dust could be an important source of lithogenic Fe required for diatom growth in the Ross Sea. Here we investigate the provenance of size-selected dust deposited on sea ice in McMurdo Sound, south-western (SW) Ross Sea. The isotopic signature of McMurdo Sound dust (0.70533< 87Sr/86Sr< 0.70915 and -1.1 < εNd(0) <3.45)confirms that dust is locally sourced from the McMurdo Sound debris bands and comprises a two-component mixture of McMurdo Volcanic Group and southern Victoria Land lithologies. In addition, the provenance of lithogenic sediment trapped in the water column was investigated, and the isotopic signature (εNd(0) =3.9, 87Sr/86Sr = 0.70434) is differentiated from long-range transported dust originating from South America and Australia. Elevated lithogenic accumulation rates in deeper sediment traps in the Ross Sea suggest that sinking articles in the water column cannot simply result from dust input at the surface. This discrepancy can be best explained by significant upwelling and remobilization of lithogenic Fe from the sea floor.

  • 2053.
    Winton, V.H.L.
    et al.
    Swedish Museum of Natural History, Department of Geology. Curtin University Perth Australia.
    Dunbar, G.B.
    University of Wellington, New Zealand.
    Bertler, N.A.N.
    University of Wellington, New Zealand.
    Millet, M.-A
    University of Wellington, New Zealand.
    Delmonte, B
    University of Milano-Bicocca, Milano Italy.
    Atkins, C.B.
    Durham University, Durham UK.
    Chewings, J.M.
    University of Wellington, New Zealand.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    The contribution of aeolian sand and dust to iron fertilization of phytoplankton blooms in southwestern Ross Sea, Antarctica2014In: Global Biogeochemical Cycles, ISSN 0886-6236, E-ISSN 1944-9224Article in journal (Refereed)
  • 2054.
    Winton, V.H.L.
    et al.
    Curtin University.
    Edwards, R
    Curtin University.
    Delmonte, B
    University of Milano-Bicocca.
    Ellis, A
    Curtin University.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    Bowie, A
    University of Tasmania.
    Bertler, N.A.N.
    University of Wellington.
    Neff, P.
    University of Rochester.
    Tuohy, A
    University of Wellington.
    Multiple sources of soluble atmospheric iron to Antarctic waters2016In: Global Biogeochemical Cycles, ISSN 0886-6236, E-ISSN 1944-9224, Vol. 30, no 3, p. 421-437Article in journal (Refereed)
    Abstract [en]

    The Ross Sea, Antarctica, is a highly productive region of the Southern Ocean. Significant new sources of iron (Fe) are required to sustain phytoplankton blooms in the austral summer. Atmospheric deposition is one potential source. The fractional solubility of Fe is an important variable determining Fe availability for biological uptake. To constrain aerosol Fe inputs to the Ross Sea region, fractional solubility of Fe was analyzed in a snow pit from Roosevelt Island, eastern Ross Sea. In addition, aluminum, dust, and refractory black carbon (rBC) concentrations were analyzed, to determine the contribution of mineral dust and combustion sources to the supply of aerosol Fe. We estimate exceptionally high dissolved Fe (dFe) flux of 1.2 × 10−6 g m−2 y−1 and total dissolvable Fe flux of 140 × 10−6 g m−2 y−1 for 2011/2012. Deposition of dust, Fe, Al, and rBC occurs primarily during spring-summer. The observed background fractional Fe solubility of ~0.7% is consistent with a mineral dust source. Radiogenic isotopic ratios and particle size distribution of dust indicates that the site is influenced by local and remote sources. In 2011/2012 summer, relatively high dFe concentrations paralleled both mineral dust and rBC deposition. Around half of the annual aerosol Fe deposition occurred in the austral summer phytoplankton growth season; however, the fractional Fe solubility was low. Our results suggest that the seasonality of dFe deposition can vary and should be considered on longer glacial-interglacial timescales.

  • 2055.
    Winton, V.H.L.
    et al.
    Curtin University Perth Australia.
    Edwards, R.
    Curtin University Perth Australia.
    Delmonte, B.
    University of Milano-Bicocca, Milan, Italy.
    Ellis, A
    Curtin University, Perth, Australia.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    Bowie, A
    University of Tasmania, Hobart, Australia.
    Bertler, N.A.N.
    University of Wellington, Wellington, New Zealand.
    Neff, P.
    University of Rochester, Rochester, New York.
    Tuohy, A.
    University of Wellington, Wellington, New Zealand.
    Multiple sources of soluble atmospheric iron to Antarctic waters2016In: Global Biogeochemical Cycles, ISSN 0886-6236, E-ISSN 1944-9224Article in journal (Refereed)
  • 2056.
    Wohlfarth, Barbara
    et al.
    Department of Geological Sciences and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Muschitiello, Francesco
    Department of Geological Sciences and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Greenwod, Sarah
    Department of Geological Sciences and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Andersson, August
    Department of Applied Environmental Science and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Kylander, Makin
    Department of Geological Sciences and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Smittenberg, Rienk
    Department of Geological Sciences and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Steinthorsdottir, Margret
    Swedish Museum of Natural History, Department of Paleobiology.
    Watson, Jenny
    School of Geography, Archaeology and Palaeoecology, Queen's University Belfast, Belfast, UK.
    Whitehouse, Nicola
    School of Geography, Earth and Environmental Sciences, Plymouth University, Plymouth, UK.
    Hässeldala – a key site for Last Termination events in southern Sweden2017In: Boreas, ISSN 0300-9483, E-ISSN 1502-3885, Vol. 46, p. 143-161Article in journal (Refereed)
    Abstract [en]

    The Last Termination (19 000–11 000 a BP) with its rapid and distinct climate shifts provides a perfect laboratory to study the nature and regional impact of climate variability. The sedimentary succession from the ancient lake at Hässeldala Port in southern Sweden with its distinct Lateglacial/early Holocene stratigraphy (>14.1–9.5 cal. ka BP) is one of the few chronologically well-constrained, multi-proxy sites in Europe that capture a variety of local and regional climatic and environmental signals. Here we present Hässeldala's multi-proxy records (lithology, geochemistry, pollen, diatoms, chironomids, biomarkers, hydrogen isotopes) in a refined age model and place the observed changes in lake status, catchment vegetation, summer temperatures and hydroclimate in a wider regional context. Reconstructed mean July temperatures increased between c. 14.1 and c. 13.1 cal. ka BP and subsequently declined. This latter cooling coincided with drier hydroclimatic conditions that were probably associated with a freshening of the Nordic Seas and started a few hundred years before the onset of Greenland Stadial 1 (c. 12.9 cal. ka BP). Our proxies suggest a further shift towards colder and drier conditions as late as c. 12.7 cal. ka BP, which was followed by the establishment of a stadial climate regime (c. 12.5–11.8 cal. ka BP). The onset of warmer and wetter conditions preceded the Holocene warming over Greenland by c. 200 years. Hässeldala's proxies thus highlight the complexity of environmental and hydrological responses across abrupt climate transitions in northern Europe.

  • 2057. Woodard, J.
    et al.
    Tuisku, P.
    Kärki, A.
    Lahaye, Y.
    Majka, J.
    Huhma, H.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Zircon and monazite geochronology of deformation in the Pielavesi Shear Zone, Finland: multistage evolution of the Archaean–Proterozoic boundary in the Fenoscandian Shield.2017In: Journal of the Geological Society, ISSN 0016-7649, E-ISSN 2041-479X, Vol. 174, p. 255-267Article in journal (Refereed)
    Abstract [en]

    The Raahe–Ladoga Shear Complex is a major crustal structure representing the Archaean–Palaeoproterozoic boundary in the Fennoscandian Shield. The complex developed during the Svecofennian Orogeny (c. 1.9 – 1.8 Ga) beginning with regional thrust tectonic phases D1 and D2, followed by large-scale shearing events D3 and D4. The Pielavesi Shear Zone is a vertical north–south-trending shear zone within the Raahe–Ladoga Shear Complex formed during regional D3 shearing and later reactivated during the regional D4 phase. Three north–south-trending elongate granitoid intrusions were selected as representative of silicic melts that intruded the transtensional Pielavesi Shear Zone during the regional D3 phase. The oriented magmatic fabric of the granitoids indicates that they intruded coeval to the deformation event. The zircon U–(Th)–Pb secondary ionization mass spectrometry (SIMS) ages of these intrusions (1888 ± 4, 1884 ± 6 and 1883 ± 5 Ma) overlap within error and provide a direct age for the regional D3 deformation. εHf(T)(−1.1 to +3.4) and εNd(T) (−1.2 to +0.4) values from these granitoids are both consistent with a predominantly juvenile source affected by a minor Archaean component. U–(Th)–Pb SIMS analyses of metamorphic monazite formed within a crosscutting blastomylonite provide an age for the regional D4phase and associated fluid activity of 1793 ± 3 Ma.

  • 2058. Workman, C.
    et al.
    Dalen, L.
    Vartanyan, S.
    Shapiro, B.
    Kosintsev, P.
    Sher, A.
    Gotherstrom, A.
    Barnes, I.
    Population-level genotyping of coat colour polymorphism in woolly mammoth (Mammuthus primigenius)2011In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 30, no 17-18, p. 2304-2308Article in journal (Refereed)
  • 2059. Workman, Claire
    et al.
    Dalen, Love
    Vartanyan, Sergey
    Shapiro, Beth
    Kosintsev, Pavel
    Sher, Andrei
    Gotherstrom, Anders
    Barnes, Ian
    Population-level genotyping of coat colour polymorphism in woolly mammoth (Mammuthus primigenius)2011In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 30, no 17-18, p. 2304-2308Article in journal (Refereed)
  • 2060.
    Wortberg, Katharina
    et al.
    Luleå Technical University.
    Conrad, Sarah
    Luleå Technical University.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    Ingri, Johan
    Luleå Technical University.
    Strontium Isotopes - A Tracer for River Suspended Iron Aggregates2017In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 95, p. 85-90Article in journal (Refereed)
    Abstract [en]

    The Kalix River shows distinct temporal variations in the Sr-isotope ratio in filtered water (0.726 to 0.732). During base flow in winter the 87Sr/86Sr ratio is on average 0.730. When discharge increases and peaks during spring flood the 87Sr/86Sr ratio shows the most radiogenic (0.732) values. The temporal variations in the 87Sr/86Sr ratio in the Kalix River can be explained by mixing of water from the woodlands and the mountain areas.

    During high water discharge in May the 87Sr/86Sr ratios are more radiogenic in the suspended phase (1 kDa - 70 µm) compared to the truly dissolved phase (<1 kDa). The difference in 87Sr/86Sr ratio between the two phases (Δ 87Sr/86Sr) is linearly correlated with the suspended iron concentration. During spring flood Sr and Fe derived from an additional source, reach the river. Deep groundwater has a more radiogenic 87Sr/86Sr isotope ratio than the Kalix River during spring flood and thus, represents a possible source for the suspended Fe and the associated Sr. Strontium can be coprecipitated with and adsorbed to different types of Fe aggregates. We propose that the Sr-isotope ratio in the suspended phase reflects the isotopic composition of the water at the interface between anoxic groundwater and oxic stream water in the riparian zone, where the Fe aggregates are formed. These particles dominate the suspended phase in the river and the mixing with mountain waters, poor in Fe, produces the difference in the isotopic signature. The different signatures in suspended and truly dissolved fraction indicate that these aggregates are relatively stable during stream-river transport. As such the 87Sr/86Sr can be used to trace the origin of the non-detrital suspended phase.

  • 2061. Xenikoudakis, G.
    et al.
    Ersmark, E.
    Tison, J. -L
    Waits, L.
    Kindberg, J.
    Swenson, J. E.
    Dalen, L.
    Consequences of a demographic bottleneck on geneticstructure and variation in the Scandinavian brown bear2015In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 24, no 13, p. 3441-3454Article in journal (Refereed)
  • 2062.
    Xu, Dong-Xian
    et al.
    College of Life Sciences, Beijing Normal University, Beijing 100875, People’s Republic of China.
    Razafimandimbison, Sylvain
    Swedish Museum of Natural History, Department of Botany.
    Mycetia griffithii, a new name for Mycetia angustifolia (Hook.f.) Razafim. & B.Bremer (Rubiaceae)2016In: Phytotaxa, ISSN 1179-3155, Vol. 252, no 3, p. 231-232Article in journal (Refereed)
  • 2063. Xu, M.
    et al.
    Qui, Yan-Ling
    Bignert, Anders
    Swedish Museum of Natural History, Department of.
    Zhou, Y.
    Zhu, Z.
    Zhao, J.
    Organochlorines in free-range hen and duck eggs from Shanghai: occurrence and risk assessment2015In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499Article in journal (Refereed)
  • 2064. Yamaguchi, Nobuyuki
    et al.
    Cooper, Alan
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Macdonald, David W.
    Evolution of the mane and group-living in the lion (Panthera leo): a review2004In: Journal of Zoology, ISSN 0952-8369, E-ISSN 1469-7998, Vol. 263, p. 329-342Article in journal (Refereed)
    Abstract [en]

    The evolutionary history of the lion Panthera leo began in Pliocene east Africa, as open habitats expanded towards the end of the Cenozoic. During the middle–late Pleistocene, lions spread to most parts of Eurasia, North America, and may have eventually reached as far south as Peru. Lions probably evolved group-living behaviour before they expanded out of Africa, and this trait is likely to have prevailed in subsequent populations. The first lions were presumed to have been maneless, and maneless forms seem to have persisted in Europe, and possibly the New World, until around 10 000 years ago. The maned form may have appeared c. 320 000–190 000 years ago, and may have had a selective advantage that enabled it to expand to replace the range of earlier maneless forms throughout Africa and western Eurasia by historic times: ‘latest wave hypothesis’.

  • 2065. Yamaguchi, Nobuyuki
    et al.
    Driscoll, Carlos A.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Abramov, Alexei V.
    Csorba, Gabor
    Cuisin, Jacques
    Fernholm, Bo
    Swedish Museum of Natural History, Department of Zoology.
    Hiermeier, Michael
    Hills, Daphne
    Hunter, Luke
    Itakura, Hiroyuki
    Johansson, Ulf S.
    Swedish Museum of Natural History, Department of Zoology.
    Kascheev, Vitaliy
    Krohmann, Katrin
    Martin, Thomas
    Nowak-Kemp, Malgosia
    Pavlinov, Igor Ya.
    Renoud, Francis
    Tomsett, Louise
    van der Mije, Steven
    Zholnerovskaya, Elena
    Groves, Colin
    Kitchener, Andrew C.
    Nijman, Vincent
    Macdonald, David W.
    Locating specimens of extinct tiger (Panthera tigris) subspecies: Javan tiger (P. t. sondaica), Balinese tiger (P. t. balica), and Caspian tiger (P. t. virgata), including previously unpublished specimens2013In: Mammal Study, ISSN 1343-4152, E-ISSN 1348-6160, Vol. 38, p. 187-198Article in journal (Refereed)
  • 2066. Yamaguchi, Tatsuhiko
    et al.
    Goedert, James L.
    Kiel, Steffen
    Swedish Museum of Natural History, Department of Paleobiology.
    Marine ostracodes from Paleogene hydrocarbon seep deposits in Washington State, USA and their ecological structure2016In: Geobios, ISSN 0016-6995, E-ISSN 1777-5728, Vol. 49, no 5, p. 407-422Article in journal (Refereed)
  • 2067. Yan, Hai-Fei
    et al.
    Zhang, Cai-Yun
    Anderberg, Arne Alfred
    Swedish Museum of Natural History, Department of Botany.
    Hao, Gang
    Ge, Xue-Jun
    Wiens, John J.
    What explains high plant richness in East Asia? Time anddiversification in the tribe Lysimachieae (Primulaceae)2018In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 219, p. 436-448Article in journal (Refereed)
    Abstract [en]

    What causes the disparity in biodiversity among regions is a fundamental question in bio-geography, ecology, and evolutionary biology. Evolutionary and biogeographic processes(speciation, extinction, dispersal) directly determine species richness patterns, and can bestudied using integrative phylogenetic approaches. However, the strikingly high richness ofEast Asia relative to other Northern Hemisphere regions remains poorly understood from thisperspective. Here, for the first time, we test two general hypotheses (older colonization time,faster diversification rate) to explain this pattern, using the plant tribe Lysimachieae (Primu-laceae) as a model system.We generated a new time-calibrated phylogeny for Lysimachieae (13 genes, 126 species),to estimate colonization times and diversification rates for each region and to test the relativeimportance of these two factors for explaining regional richness patterns.We find that neither time nor diversification rates alone explain richness patterns amongregions in Lysimachieae. Instead, a new index that combines both factors explains global rich-ness patterns in the group and their high East Asian biodiversity.Based on our results from Lysimachieae, we suggest that the high richness of plants in EastAsia may be explained by a combination of older colonization times and faster diversificationrates in this region

  • 2068. Yang, L.
    et al.
    Johanson, Kjell Arne
    Swedish Museum of Natural History, Department of Zoology. Swedish Museum of Natural History.
    Description of a new Helicopsyche species from China (Trichoptera: Helicopsychidae)2004In: Aquatic Insects, ISSN 0165-0424, E-ISSN 1744-4152, Vol. 26, p. 65-68Article in journal (Refereed)
  • 2069. Yashanew, F.G.
    et al.
    Pease, V.
    Abdelsalam, M.G.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Zircon U–Pb ages, δ18O and whole-rock Nd isotopic compositions of the Dire Dawa Precambrian basement, eastern Ethiopia: implications for the assembly of Gondwana2016In: Journal of the Geological Society, ISSN 0016-7649, E-ISSN 2041-479X, Vol. 172, p. 142-156Article in journal (Refereed)
    Abstract [en]

    New high spatial resolution secondary ion mass spectrometry (SIMS) zircon dating from the Dire Dawa Precambrian basement yields crystallization ages at c. 790 Ma and 600 – 560 Ma. Two of the youngest samples are pervasively deformed, indicating that orogenesis continued until c. 560 Ma. SIMS δ18Ozrn shows bimodality, with the oldest sample (c. 790 Ma) and inherited zircons of that age in the younger samples having values of 7.8 – 9.6‰, whereas the Ediacaran samples have δ18Ozrn values of 4.9 – 7.2‰. These δ18Ozrn ratios are higher than mantle values and indicate a supracrustal input to the source of the Dire Dawa granitoids. All samples have unradiogenic εNd(t) values of −10.3 to −5.8 and Nd model ages of 1.72 – 1.42 Ga. These attributes suggest that the Dire Dawa granitoids were mostly derived from reworking of long-lived crustal sources. The occurrence of c. 580 – 550 Ma orogenesis in both the Dire Dawa basement and the juvenile Western Ethiopian Shield and the confinement of c. 630 Ma metamorphism to only the latter indicate that these two lithospheric blocks of contrasting isotopic compositions amalgamated at c. 580 – 550 Ma. This suggests that the Mozambique Ocean, which separated these two lithospheric blocks, was completely consumed during the late Ediacaran to early Cambrian.

  • 2070.
    Yeshanew, Fitsum G.
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Pease, V.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Al-Khirbash, S.
    Zircon U–Pb geochronology and Nd isotope systematics of the Abas terrane, Yemen: Implications for Neoproterozoic crust reworking events.2015In: Precambrian Research, ISSN 0301-9268, E-ISSN 1872-7433, Vol. 267, p. 106-120Article in journal (Refereed)
    Abstract [en]

    High-spatial-resolution secondary-ion mass spectrometry (SIMS) U–Pb zircon ages, whole-rock Nd isotopic and geochemical data are reported for granites and granitic gneisses from a traverse across the Abas terrane, Yemen, a part of the Precambrian basement of southern Arabian Peninsula. SIMS U–Pb dating identifies two magmatic episodes, the first at c. 790–725 Ma represented by granitic gneisses, the second clearly post-tectonic at c. 625–590 Ma. The oldest sample in the post-tectonic group is slightly deformed while younger samples are undeformed indicating that penetrative deformation ceased at c. 625 Ma in the Abas region. Whole-rock Nd(t) values between −11 and +0.8, Nd model ages of 1.70–1.13 Ga indicate a significant contribution of evolved continental material in the genesis of the Abas granitoids, unlike most of the juvenile Arabian-Nubian Shield (ANS), although there are few inherited zircons. Secular variation in ɛNd(t) reflects a change in magma source with increasing juvenile magma and diminishing crustal input during post-tectonic (625–590 Ma) magmatism. The combination of subduction zone chemistry, absence of older rocks, paucity of inherited zircons, evolved Nd isotopic signatures and the I-type characteristics of the samples suggest that assimilation occurred at depth.

  • 2071. Yin, Zongjun
    et al.
    Cunningham, John A.
    Vargas, Kelly
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Zhu, Maoyan
    Donoghue, Philip C.J.
    University of Bristol.
    Nuclei and nucleoli in embryo-like fossils from the Ediacaran Weng’an Biota.2017In: Precambrian Research, ISSN 0301-9268, E-ISSN 1872-7433, Vol. 301, p. 145-151Article in journal (Refereed)
    Abstract [en]

    The embryo-like microfossils from the Ediacaran Weng’an Biota (ca. 609 million years old) are among the oldest plausible claims of animals in the fossil record. Fossilization frequently extends beyond the cellular, to preserve subcellular structures including contentious Large Intracellular Structures (LISs) that have been alternately interpreted as eukaryote nuclei or organelles, degraded remains, or abiological structures. Here we present new data on the structure, morphology, and development of the LISs in these embryo-like fossils, based on Synchrotron Radiation X-ray Tomographic Microscopy (SRXTM) and quantitative computed tomographic analysis. All the lines of evidence, including consistency in the number, shape, position, and relative size (LIS-to-cytoplasm ratio) of the LISs, as well as their occurrence within preserved cytoplasm, support their interpretation as cell nuclei. Our results allow us to reject the view that nuclei cannot be preserved in early eukaryote fossils, offering new potential for interpreting the fossil record of early eukaryote evolution.

  • 2072.
    Yuan, Bo
    et al.
    Stockholms universitet.
    Vorkamp, Katrin
    Århus universitet.
    Roos, Anna
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Faxneld, Suzanne
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Sonne, Christian
    Århus universitet.
    Garbus, Svend Erik
    Århus universitet.
    Lind, Ylva
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Eulaers, Igor
    Århus universitet.
    Hellström, Peter
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Dietz, Rune
    Århus universitet.
    Persson, Sara
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Bossi, Rossana
    Århus universitet.
    de Wit, Cynthia
    Stockholms universitet.
    Accumulation of short-, medium-, and long-chain chlorinated paraffins in marine and terrestrial animals from Scandinavia2019In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 53, p. 3526-3537Article in journal (Refereed)
  • 2073.
    Yuan, Qin
    et al.
    baKey Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining,Qinghai 810008, China.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Li, Qing-Kuan
    University of Chinese Academy of Sciences, Beijing 100049, China.
    Fan, Qi-Shun
    Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, China.
    Wei, Hai-Cheng
    Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, China.
    Qin, Zhan-Jie
    Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, China.
    Zhang, Xiang-Ru
    University of Chinese Academy of Sciences, Beijing 100049, China.
    Shan, Fa-Shou
    Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, China.
    A late Eocene palynological record from the Nangqian Basin, TibetanPlateau: Implications for stratigraphy and paleoclimate2017In: Palaeoworld, ISSN 1871-174X, Vol. 26, p. 369-379Article in journal (Refereed)
    Abstract [en]

    With the uplifting, large-scale thrusting and striking of the Tibetan Plateau, several Paleogene intracontinental basins formed within the northernTibetan Plateau (TP). Stratigraphical and paleoenvironmental studies of the sedimentary successions within these basins are critical for understandingPaleogene climatological changes in Eurasia. The Nangqian Basin, one of such basins, formed in the Yushu area of the northeastern Tibetan Plateau.A set of lacustrine sediments, dominated by red clasolite, marlite, and gypsum, developed in the Yang Ala section in this basin. Paleontologicalrecords from the Nangqian Basin remain poorly known. Here, we investigate the palynological assemblages of one sedimentary succession at theYang Ala section that belongs to the Gongjue Formation, and their implications regarding the geological age and paleoclimate are discussed. Theresults reveal that the assemblages are dominated mainly by angiosperm pollen (tricolpates and tricolporate), including

    Nitrariadites (Pokrovskaja), Quercoidites, and Labitricolpites, followed by gymnosperm pollen taxa, such as Ephedripites and Taxodiaceaepollenites, and sparse pteridophytespores produced by ferns. A late Eocene age is inferred based on palynostratigraphy and comparison with other pollen assemblages in the TP. Arelatively dry climate with brief humid periods is indicated by the high abundance of xerophytic pollen taxa, such as Ephedripites and Nitrariadites,which are associated with broadleaved deciduous and evergreen plants. The characteristics of the pollen assemblages from the studied Yang Alasection are consistent with other Cenozoic palynofloras from the Mahalagou Formation in the Xining Basin and with those of the Yaxicuo Groupin the Hoh Xil Basin. These results provide an improved stratigraphical scheme for parts of the Cenozoic and enrich the current knowledge of thevegetation history of the northeastern Tibetan Plateau.

  • 2074. Zachrisson, Inger
    et al.
    Werdelin, LarsSwedish Museum of Natural History, Department of Paleobiology.
    Gravfält i Fångstmarken1984Collection (editor) (Other academic)
  • 2075.
    Zack, Thomas
    et al.
    Göteborgs Universitet.
    Kooijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    Petrology and geochronology of rutile2017In: Petrochronology: Methods and Applications / [ed] Matthew J. Kohn, Martin Engi, Pierre Lanari, Chantilly, USA: Mineralogical Society of America, 2017, p. 443-467Chapter in book (Refereed)
    Abstract [en]

    Rutile (TiO2) is an important accessory mineral that, when present, offers a rich source of information about the rock units in which it is incorporated. It occurs in a variety of specific microstructural settings, contains significant amounts of several trace elements and is one of the classical minerals used for U–Pb age determination. Here, we focus on information obtainable from rutile in its original textural context. We do not present an exhaustive review on detrital rutile in clastic sediments, but note that an understanding of the petrochronology of rutile in its source rocks will aid interpretation of data obtained from detrital rutile. For further information on the important role of rutile in provenance studies, the reader is referred to previous reviews (e.g., Zack et al. 2004b; Meinhold 2010; Triebold et al. 2012). Coarse rutile is the only stable TiO2 polymorph under all crustal and upper mantle conditions, with the exception of certain hydrothermal environments (Smith et al. 2009). As such, we will focus on rutile rather than the polymorphs brookite, anatase and ultrahigh-pressure modifications.

    In this chapter, we first review rutile occurrences, trace element geochemistry, and U–Pb geochronology individually to illustrate the insights that can be gained from microstructures, chemistry and ages. Then, in the spirit of petrochronology, we show the interpretational power of combining these approaches, using the Ivrea Zone (Italy) as a case study. Finally, we suggest some areas of future research that would improve petrochronologic research using rutile.

  • 2076. Zale, R.
    et al.
    Huang, Y. -T
    Bigler, C.
    Wood, J. R.
    Dalén, L.
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Wang, X. -R
    Segerstrom, U.
    Klaminder, J.
    Growth of plants on the Late Weichselian ice-sheet during Greenland interstadial-1?2018In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 185, p. 222-229Article in journal (Refereed)
  • 2077. Zamora, J.C.
    et al.
    Diederich, P.
    Millanes, A.M.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    An old familiar face: Tremella anaptychiae sp. nov. (Tremellales,Basidiomycota).2017In: Phytotaxa, ISSN 1179-3155, E-ISSN 1179-3163, Vol. 307, p. 254-262Article in journal (Refereed)
  • 2078. Zamora, J.C.
    et al.
    Hansen, Karen
    Swedish Museum of Natural History, Department of Botany.
    Kosuthova, Alica
    Prieto, Maria
    Swedish Museum of Natural History, Department of Botany.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Considerations and consequences of allowing DNA sequence data as types of fungal taxa2018In: IMA Fungus, ISSN 2210-6340, E-ISSN 2210-6359, Vol. 9, p. 167-175Article in journal (Refereed)
  • 2079. Zamora, J.C.
    et al.
    Millanes, A.M.
    Etayo, J.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Tremella mayrhoferi, a new lichenicolous species on Lecanora allophana2018In: Herzogia, ISSN 0018-0971, Vol. 31, p. 666-676Article in journal (Refereed)
  • 2080. Zamora, J.C.
    et al.
    Millanes, A.M.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Rico, V.
    Perez-Ortega, S.
    Understanding lichenicolous heterobasidiomycetes: new taxa and reproductive innovations in Tremella s. lat.2016In: Mycologia, ISSN 0027-5514, E-ISSN 1557-2536, Vol. 108, p. 381-396Article in journal (Refereed)
  • 2081. Zamora, Samuel
    et al.
    Lefebvre, Bertrand
    Hosgör, Izzet
    Franzén, Christina
    Swedish Museum of Natural History, Department of Paleobiology.
    Nardin, Elise
    Fatka, Oldřich
    Álvaro, José Javier
    The Cambrian edrioasteroid Stromatocystites (Echinodermata): Systematics, palaeogeography, and palaeoecology.2015In: Geobios, ISSN 0016-6995, E-ISSN 1777-5728, Vol. 48, no 5, p. 417-426Article in journal (Refereed)
    Abstract [en]

    The Cambrian edrioasteroid Stromatocystites is reported and described from Spain, Sweden and Turkey. All previously known occurrences of the genus are critically reviewed, and S. flexibilis is reinterpreted as a junior synonym of S. pentangularis. Stromatocystites was biogeographically widespread and colonized different areas of Baltica, Gondwana (Arabian, eastern and western margins) and Laurentia (western Newfoundland). Stratigraphically, it ranges from Cambrian Series 2, Stage 4 to Cambrian Series 3, Drumian. Stromatocystites lived in quiet water environments with stabilized substrates. It was attached directly to the substrate by its aboral surface. As these environments were widespread throughout Baltica, Gondwana and Laurentia, availability of suitable substrates for larval settlement and oceanic palaeocurrents led to the successful development of Stromatocystites colonies.

  • 2082. Zanatta, Florian
    et al.
    Vanderpoorten, Alain
    Hedenäs, Lars
    Swedish Museum of Natural History, Department of Botany.
    Johansson, Victor
    Patiño, Jairo
    Lönnell, Niklas
    Hylander, Kristoffer
    Under which humidity conditions are moss spores released? A comparison between species with perfect and specialized peristomes2018In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, p. 11484-11491Article in journal (Refereed)
  • 2083. Zaton, M
    et al.
    Niedzwiedzki, G
    Marynowski, L
    Benzerara, K
    Pott, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Cosmidis, J
    Krzykawski, T
    Filipiak, P
    Coprolites of Late Triassic carnivorous vertebrates from Poland: An integrative approach2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 430, p. 21-46Article in journal (Refereed)
    Abstract [en]

    Vertebrate coprolites derived from Upper Triassic terrestrial deposits of southern Poland have been subjected to various analytical methods in order to retrieve information about their composition, producer’s diet and nature of the microscopic structures preserved in the groundmass. Morphologically, the coprolites have been classified into four morphotypes, of which only three were further analysed due to their good state of preservation. Their groundmass are composed of francolite, a carbonate-rich apatite, in which abundant coccoid structures are preserved. Based on various microscopic and organic geochemical techniques, they are interpreted as fossilized bacteria which could have mediated the phosphatization of the faeces. The thin sectioning revealed that the coprolites consist of those containing exclusively bone remains, and those preserving both bone and plant remains. Those coprolites preserving only vertebrate remains are suggestive for exclusive carnivorous diet of the producers. However, the interpretation of coprolites consisting of both vertebrate and plant remains is more debatable. Although they may attest to omnivory, it cannot be excluded that potential producers were carnivorous and occasionally ingested plants, or accidentally swallowed plant material during feeding. The latter may involve predation or scavenging upon other herbivorous animals. The potential producers may have been animals that foraged in or near aquatic habitats, such as semi-aquatic archosaurs and/or temnospondyls. This is supported by the presence of ostracode and other aquatic arthropod remains, and fish scales within the coprolites, as well as by the presence of specific biomarkers such as phytanic and pristanic acids, which are characteristic constituents of fish oil. The preservation of such labile organic compounds as sterols, palmitin, stearin or levoglucosan attests for rapid, microbially-mediated mineralization of the faeces at very early stages of diagenesis.

  • 2084.
    Zepeda Mendoza, Marie Lisandra
    et al.
    Natural History Museum of Denmark.
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Campos, Paula
    University of Copenhagen.
    Nylander, Johan A. A.
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Sallstedt, Thereese
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Dalén, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Metagenomic Analysis from the Interior of a Speleothem in Tjuv-Ante's Cave, Northern Sweden2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3, p. 1-23, article id e015177Article in journal (Refereed)
    Abstract [en]

    Speleothems are secondary mineral deposits normally formed by water supersaturated with calcium carbonate percolating into underground caves, and are often associated with low-nutrient and mostly non-phototrophic conditions. Tjuv-Ante’s cave is a shallow-depth cave formed by the action of waves, with granite and dolerite as major components, and opal-A and calcite as part of the speleothems, making it a rare kind of cave. We generated two DNA shotgun sequencing metagenomic datasets from the interior of a speleothem from Tjuv-Ante’s cave representing areas of old and relatively recent speleothem formation. We used these datasets to perform i) an evaluation of the use of these speleothems as past biodiversity archives, ii) functional and taxonomic profiling of the speleothem’s different formation periods, and iii) taxonomic comparison of the metagenomic results to previous microscopic analyses from a nearby speleothem of the same cave. Our analyses confirm the abundance of Actinobacteria and fungi as previously reported by microscopic analyses on this cave, however we also discovered a larger biodiversity. Interestingly, we identified photosynthetic genes, as well as genes related to iron and sulphur metabolism, suggesting the presence of chemoautotrophs. Furthermore, we identified taxa and functions related to biomineralization. However, we could not confidently establish the use of this type of speleothems as biological paleoarchives due to the potential leaching from the outside of the cave and the DNA damage that we propose has been caused by the fungal chemical etching.

  • 2085. Zhang, Chi
    et al.
    Rannala, Bruce
    Yang, Ziheng
    Bayesian species delimitation can be robust to guide tree inference errors2014In: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 63, no 6, p. 993-1004Article in journal (Refereed)
  • 2086. Zhang, Chi
    et al.
    Rannala, Bruce
    Yang, Ziheng
    Robustness of compound Dirichlet priors for Bayesian inference of branch lengths2012In: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 61, no 5, p. 779-784Article in journal (Refereed)
    Abstract [en]

    We modified the phylogenetic program MrBayes 3.1.2 to incorporate the compound Dirichlet priors for branch lengths proposed recently by Rannala, Zhu, and Yang (2012. Tail paradox, partial identifiability and influential priors in Bayesian branch length inference. Mol. Biol. Evol. 29:325-335.) as a solution to the problem of branch-length overestimation in Bayesian phylogenetic inference. The compound Dirichlet prior specifies a fairly diffuse prior on the tree length (the sum of branch lengths) and uses a Dirichlet distribution to partition the tree length into branch lengths. Six problematic data sets originally analyzed by Brown, Hedtke, Lemmon, and Lemmon (2010. When trees grow too long: investigating the causes of highly inaccurate Bayesian branch-length estimates. Syst. Biol. 59:145-161) are reanalyzed using the modified version of MrBayes to investigate properties of Bayesian branch-length estimation using the new priors. While the default exponential priors for branch lengths produced extremely long trees, the compound Dirichlet priors produced posterior estimates that are much closer to the maximum likelihood estimates. Furthermore, the posterior tree lengths were quite robust to changes in the parameter values in the compound Dirichlet priors, for example, when the prior mean of tree length changed over several orders of magnitude. Our results suggest that the compound Dirichlet priors may be useful for correcting branch-length overestimation in phylogenetic analyses of empirical data sets.

  • 2087. Zhang, Chi
    et al.
    Stadler, Tanja
    Klopfstein, Seraina
    Heath, Tracy A.
    Ronquist, Fredrik
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Total-evidence dating under the fossilized birth–death process2016In: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 65, no 2, p. 228-249Article in journal (Refereed)
  • 2088. Zhang, Chi
    et al.
    Zhang, De-Xing
    Zhu, Tianqi
    Yang, Ziheng
    Evaluation of a Bayesian coalescent method of species delimitation2011In: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 60, no 6, p. 747-761Article in journal (Refereed)
    Abstract [en]

    A Bayesian coalescent-based method has recently been proposed to delimit species using multilocus genetic sequence data. Posterior probabilities of different species delimitation models are calculated using reversible-jump Markov chain Monte Carlo algorithms. The method accounts for species phylogenies and coalescent events in both extant and extinct species and accommodates lineage sorting and uncertainties in the gene trees. Although the method is theoretically appealing, its utility in practical data analysis is yet to be rigorously examined. In particular, the analysis may be sensitive to priors on ancestral population sizes and on species divergence times and to gene flow between species. Here we conduct a computer simulation to evaluate the statistical performance of the method, such as the false negatives (the error of lumping multiple species into one) and false positives (the error of splitting one species into several). We found that the correct species model was inferred with high posterior probability with only one or two loci when 5 or 10 sequences were sampled from each population, or with 50 loci when only one sequence was sampled. We also simulated data allowing migration under a two-species model, a mainland-island model and a stepping-stone model to assess the impact of gene flow (hybridization or introgression). The behavior of the method was diametrically different depending on the migration rate. Low rates at < 0.1 migrants per generation had virtually no effect, so that the method, while assuming no hybridization between species, identified distinct species despite small amounts of gene flow. This behavior appears to be consistent with biologists' practice. In contrast, higher migration rates at ≥ 10 migrants per generation caused the method to infer one species. At intermediate levels of migration, the method is indecisive. Our results suggest that Bayesian analysis under the multispecies coalescent model may provide important insights into population divergences, and may be useful for generating hypotheses of species delimitation, to be assessed with independent information from anatomical, behavioral, and ecological data.

  • 2089. Zhang, Fucheng
    et al.
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    Zhou, Zhonghe
    Description of a new enantiornithine bird from the Early Cretaceous of Hebei, northern China2004In: Canadian journal of earth sciences (Print), ISSN 0008-4077, E-ISSN 1480-3313, Vol. 41, no 9, p. 1097-1107Article in journal (Refereed)
    Abstract [en]

    This paper describes a new enantiornithine fossil bird, Vescornis hebeiensis, nov. sp. from the Early Cretaceous of China. We refer Vescornis to the crown clade Euenantiornithes based on several characteristics observed in the thoracic girdle and wing. Vescornis also exhibits characteristics that separate it from other enantiornithine birds, such as the short alular phalanx, the vestigial manual claws, and the well-developed and long foot claws. These features suggest an adaptation towards an improved flight capability, while the ability of Vescornis to climb is reduced compared with many other enantiornithine birds.

  • 2090. Zhang, Ruiying
    et al.
    Song, Gang
    Qu, Yanhua
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
    Alström, Per
    Ramos, Raül
    Xing, Xiaoying
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    Fjeldså, Jon
    Wang, Haitao
    Yang, Xiaojun
    Kristin, Anton
    Shestopalov, Alexander M
    Choe, Jae Chun
    Lei, Fumin
    Comparative phylogeography of two widespread magpies: importance of habitat preference and breeding behavior on genetic structure in China.2012In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 65, no 2, p. 562-72Article in journal (Refereed)
    Abstract [en]

    Historical geological events and climatic changes are believed to have played important roles in shaping the current distribution of species. However, sympatric species may have responded in different ways to such climatic fluctuations. Here we compared genetic structures of two corvid species, the Azure-winged Magpie Cyanopica cyanus and the Eurasian Magpie Pica pica, both widespread but with different habitat dependence and some aspects of breeding behavior. Three mitochondrial genes and two nuclear introns were used to examine their co-distributed populations in East China and the Iberian Peninsula. Both species showed deep divergences between these two regions that were dated to the late Pliocene/early Pleistocene. In the East Chinese clade of C. cyanus, populations were subdivided between Northeast China and Central China, probably since the early to mid-Pleistocene, and the Central subclade showed a significant pattern of isolation by distance. In contrast, no genetic structure was found in the East China populations of P. pica. We suggest that the different patterns in the two species are at least partly explained by ecological differences between them, especially in habitat preference and perhaps also breeding behavior. These dissimilarities in life history traits might have affected the dispersal and survival abilities of these two species differently during environmental fluctuations.

  • 2091. Zhang, Z.
    et al.
    Gentry, A. W.
    Kakkinen, A.
    Liu, L.
    Lunkka, J.-P.
    Qiu, Z.
    Sen, S.
    Scott, R. S.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Zheng, S.
    Fortelius, M.
    Land mammal faunal sequence of the late Miocene of China: New evidence from Lantian, Shaanxi Province2002In: Vertebrata PalAsiatica, Vol. 40, p. 165-176Article in journal (Refereed)
  • 2092.
    Zhang, Zhifei
    et al.
    Northwest University, Xian, China.
    Holmer, Lars E.
    Uppsala Universitet.
    Brock, Glenn A.
    Macquarie University, Sydney, Australia.
    Budd, Graham E.
    Uppsala Universitet.
    Fu, Dongjing
    Northwest University, Xian, China.
    Zhang, Xingliang
    Northwest University, Xian, China.
    Shu, Degan
    Northwest University, Xian, China.
    Han, Jian
    Northwest University, Xian, China.
    Liu, Jianni
    Wang, Haizhou
    Uppsala Universitet.
    Butler, Aodhan
    Uppsala Universitet.
    Li, Guoxiang
    Nanjing Institute of Geology and Palaeontology, Nanjing, China.
    A sclerite-bearing stem group entoproct from the early Cambrian and its implications2013In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 3, no 1066, p. 1-7Article in journal (Refereed)
    Abstract [en]

    The Lophotrochozoa includes disparate tentacle-bearing sessile protostome animals, which apparently appeared in the Cambrian explosion, but lack an uncontested fossil record. Here we describe abundant well preserved material of Cotyledion tylodes Luo et Hu, 1999, from the Cambrian (Series 2) Chengjiang deposits, reinterpreted here as a stem-group entoproct. The entoproct affinity is supported by the sessile body plan and interior soft anatomy. The body consists of an upper calyx and a lower elongate stalk with a distal holdfast. The soft anatomy includes a U-shaped gut with a mouth and aboral anus ringed by retractable marginal tentacles. Cotyledion differs from extant entoprocts in being larger, and having the calyx and the stalk covered by numerous loosely-spaced external sclerites. The description of entoprocts from the Chengjiang biota traces the ancestry of yet another lophotrochozoan phylum back to the Cambrian radiation, and has important implications for the earliest evolution of lophotrochozoans.

  • 2093.
    Zhang, Zhifei
    et al.
    Northwest University, Xian, China.
    Li, Guoxiang
    Nanjing Institute of Geology and Palaeontology, Nanjing, China.
    Holmer, Lars E.
    Uppsala Universitet.
    Brock, Glenn A.
    Macquarie University, Sydney, New South Wales.
    Balthasar, Uwe
    University of Glasgow.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Fu, D.J.
    Northwest University, Xian, China.
    Zhang, X.L.
    Northwest University, Xian, China.
    Wang, Haizhou
    Uppsala Universitet.
    Butler, Aodhan
    Uppsala Universitet.
    Zhang, Z.L.
    Northwest University, Xian, China.
    Cao, C.Q.
    Nanjing Institute of Geology and Palaeontology, Nanjing, China.
    Han, J.
    Northwest University, Xian, China.
    Liu, J.N.
    Northwest University, Xian, China.
    Shu, D.G.
    Northwest University, Xian, China.
    An early Cambrian agglutinated tubular lophophorate with brachiopod characters2014In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 4, no 4682, p. 1-7Article in journal (Refereed)
    Abstract [en]

    The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen. et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagersta¨tte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long pedicle with coelomic space. The terminal bulb of the pedicle provided anchorage in soft sediment. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods.

  • 2094.
    Zhang, Zhiliang
    et al.
    Northwest university.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Zhang, Zhifei
    Northwest University.
    A hyolithid without helens preserving the oldest hyolith muscle scars; palaeobiology of Paramicrocornus from the Shujingtuo Formation (Cambrian Series 2) of South China2018In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 489, p. 1-14Article in journal (Refereed)
    Abstract [en]

    The hyolithid Paramicrocornus zhenbaensis from the lower Cambrian (Cambrian Series 2) Shuijingtuo Formation of southern Shaanxi and western Hubei provinces of the Yangtze Platform is well-preserved in three dimensions. The morphology of the conch and operculum of P. zhenbaensis shows that this species lacked helens, which are considered to be characteristic of hyolithids and hence Paramicrocornus may belong to a sister group of other hyolithids. The shell structure of P. zhenbaensis reveals close similarities to the shell structure of other hyolithids. Furthermore, the smaller size and non-radial orientation of tubules in the shell structure of the operculum also differ from that in orthothecid hyoliths, suggesting that this characteristic may be used to differentiate hyolithids and orthothecids. The phosphatized opercula of P. zhenbaensis exhibit a pair of muscle scars located close to the apex of the internal surface. These muscle scars, as well as similar structures in other hyolithids, probably served as attachment sites of muscles controlling the retraction of the tentaculate feeding organ recently discovered inhyolithids. Without helens, P. zhenbaensis may have been sessile with the conch partly buried in the sea floor.

  • 2095. Zhao, Wan-Yi
    et al.
    Fritsch, Peter W.
    Do, Van Truong
    Fan, Qiang
    Yin, Qiang-Yi
    Penneys, Darin S.
    Swenson, Ulf
    Swedish Museum of Natural History, Department of Botany.
    Liao, Wen-Bo
    Rehderodendron truongsonense (Styracaceae), a new species from Vietnam2019In: Journal of the Botanical Research Institute of Texas, ISSN 1934-5259, Vol. 13, no 1, p. 157-171Article in journal (Refereed)
    Abstract [en]

    Rehderodendron truongsonense, a new species from Vietnam, is described and illustrated. In the treatment of the Styracaceae for the Flore du Cambodge, du Laos, et du Viêtnam, specimens of this species were recognized as R. macrocarpum Hu. These specimens clearly differ from R. macrocarpum, however, as well as from all other species of Rehderodendron (where these characters are known) by, e.g., an evergreen ver- sus deciduous habit, fewer secondary veins of the leaf blade, shorter inflorescences and corolla lobes, large and conspicuous lowermost bracteoles, the presence of eight ovules per carpel, and a fruit with ca. 10 to 20 ribs that are indistinct. Phylogenetic analysis based on five chloroplast DNA regions (clpP-psbB, ndhD-psaC-ndhE-ndhG, rpl22-rps19, rps18-rpl20, and psbI-trnS-GCU) placed the new species as nested within Rehderodendron and sister to R. gongshanense. This new species is endemic to the Truong Son Mountain Range, from which the epi- thet is derived, and we assign it an IUCN Red List preliminary status as Near Threatened. 

  • 2096. Zhao, X
    et al.
    Fernández-Brime, Samantha
    Swedish Museum of Natural History, Department of Botany.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Locke, M
    Leavitt, S.D.
    Lumbsch, H. Thorsten
    Using multi-locus sequence data for addressing species boundaries in commonly accepted lichen-forming fungal species.2017In: Organisms Diversity & Evolution, ISSN 1439-6092, E-ISSN 1618-1077, Vol. 17, p. 351-363Article in journal (Refereed)
  • 2097. Zhou, Yihui
    et al.
    Asplund, Lillemor
    Yin, Ge
    Athanassiadis, Ioannis
    Wideqvist, Ulla
    Bignert, Anders
    Qiu, Yanling
    Zhu, Zhiliang
    Zhao, Jianfu
    Bergman, Åke
    Extensive organohalogen contamination in wildlife from a site in the Yangtze River Delta.2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 554-555Article in journal (Refereed)
    Abstract [en]

    The environmental and human health concerns for organohalogen contaminants (OHCs) extend beyond the 23 persistent organic pollutants (POPs) regulated by the Stockholm Convention. The current, intense industrial production and use of chemicals in China and their bioaccumulation makes Chinese wildlife highly suitable for the assessment of legacy, novel and emerging environmental pollutants. In the present study, six species of amphibians, fish and birds were sampled from paddy fields in the Yangtze River Delta (YRD) were screened for OHCs. Some extensive contamination was found, both regarding number and concentrations of the analytes, among the species assessed. High concentrations of chlorinated paraffins were found in the snake, Short-tailed mamushi (range of 200-340 μg g(-)(1)lw), Peregrine falcon (8-59 μg g(-1)lw) and Asiatic toad (97 μg g(-)(1)lw). Novel contaminants and patterns were observed; octaCBs to decaCB made up 20% of the total polychlorinated biphenyls (PCBs) content in the samples and new OHCs, substituted with 5-8 chlorines, were found but are not yet structurally confirmed. In addition, Dechlorane 602 (DDC-DBF) and numerous other OHCs (DDTs, hexachlorocyclohexanes (HCHs), polybrominated diphenyl ethers (PBDEs), hexbromocyclododecane (HBCDD), chlordane, heptachlor, endosulfan and Mirex) were found in all species analyzed. These data show extensive chemical contamination of wildlife in the YRD with a suite of OHCs with both known and unknown toxicities, calling for further in-depth studies.

  • 2098. Zhou, Yihui
    et al.
    Yin, Ge
    Asplund, Lillemor
    Qiu, Yanling
    Bignert, Anders
    Zhu, Zhiliang
    Zhao, Jianfu
    Bergman, Åke
    A novel pollution pattern: Highly chlorinated biphenyls retained in Black-crowned night heron (Nycticorax nycticorax) and Whiskered tern (Chlidonias hybrida) from the Yangtze River Delta.2016In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 150Article in journal (Refereed)
    Abstract [en]

    Contamination of organochlorine pesticides (OCPs), polychlorinated diphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and their methylated counterparts (MeO-PBDEs) were determined in Black-crowned night heron (Nycticorax nycticorax) and Whiskered tern (Chlidonias hybrida) from two drinking water sources, e.g. Tianmu lake and East Tai lake in Yangtze River Delta, China. A novel PCBs contamination pattern was detected, including 11% and 6.9% highly chlorinated biphenyls (PCBs with eight to ten chlorines) in relation to total PCB concentrations in the Black-crowned night heron and Whiskered tern eggs, respectively. The predominating OCPs detected in the present study were 4,4'-DDE, with concentration range 280-650 ng g(-1) lw in Black-crowned night heron and 240-480 ng g(-1) lw in Whiskered tern, followed by β-HCH and Mirex. 6-MeO-BDE-90 and 6-MeO-BDE-99 are the two predominant congeners of MeO-PBDEs whereas 6-OH-BDE-47 contributes mostly to the OH-PBDEs in both species. Contamination level was considered as median or low level compared global data.

  • 2099. Zimmermann, Judith
    et al.
    Wentrup, Cecilia
    Sadowski, Miriam
    Blazejak, Anna
    Gruber-Vodicka, Harald R.
    Kleiner, Manuel
    Ott, Jörg A.
    Cronholm, Bodil
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    De Wit, Pierre
    Erseus, Christer
    Dubilier, Nicole
    Closely coupled evolutionary history of ecto- and endosymbionts from two distantly related animal phyla2016In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, no 13, p. 3203-3223Article in journal (Refereed)
  • 2100. Zintzen, Vincent
    et al.
    Roberts, Clive D.
    Shepherd, Lara
    Stewart, Andrew L.
    Struthers, Carl D.
    Anderson, Marti J.
    McVeagh, Margaret
    Norén, Michael
    Swedish Museum of Natural History, Department of Zoology.
    Fernholm, Bo
    Swedish Museum of Natural History, Department of Zoology.
    Review and phylogeny of the New Zealand hagfishes (Myxiniformes: Myxinidae), with a description of three new species2015In: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 174, no 2, p. 363-393Article in journal (Refereed)
    Abstract [en]

    Hagfishes from New Zealand are reviewed and a phylogeny proposed using morphological and genetic data (DNA sequences of cytochrome c oxidase subunit I gene, COI, and the small subunit RNA, 16S). Eptatretus cryptus sp. nov. was previously confused with Eptatretus cirrhatus (Forster in Bloch & Schneider, 1801) because of their similar morphology, and is found from the Three Kings Islands to Stewart Island and in the eastern part of the Chatham Rise (at depths of 96–922 m). Eptatretus poicilus sp. nov. is endemic to the Three Kings Islands, where it is common and associated with soft sediment and deep-sea coral-sponge habitats (114–842 m). Neomyxine caesiovitta sp. nov. is a slender hagfish found along the east coast of the North Island south to the Chatham Rise (430–1083 m). A neotype is erected for E. cirrhatus (type locality: Breaksea Sound, Fiordland), occurring widely in New Zealand coastal, shelf, and slope waters (1–922 m), but not at the Three Kings Islands. Eptatetrus goliath Mincarone & Stewart, 2006, Neomyxine biniplicata (Richardson & Jowett, 1951), and Nemamyxine elongata Richardson, 1958 are further described using additional material. Rubicundus eos (Fernholm, 1991) is still only known from the holotype (type locality: Challenger Plateau). Genetic results showed that the New Zealand Eptatretus species form a monophyletic group within the subfamily Eptatretinae, indicating likely speciation from a single common ancestor within the area. Eptatretus poicilus sp. nov. is the sister species of E. cirrhatus, and E. cryptus sp. nov. is closely associated with the clade formed by these two species. Eptatretus goliath is most closely associated with Eptatretus minor Fernholm & Hubbs, 1981 (Gulf of Mexico), these two species basally diverging within New Zealand hagfishes. The endemic genus Neomyxine forms a well-supported monophyletic group of as yet uncertain position within the phylogenetic tree. A key to the New Zealand hagfishes, fresh colour photographs, distribution maps, and in situ video recordings are presented

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