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  • 2051.
    Swenson, Ulf
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Nylinder, Stephan
    Swedish Museum of Natural History, Department of Botany.
    Munzinger, Jérôme
    Towards a natural classification of Sapotaceae subfamily Chrysophylloideae in Oceania and Southeast Asia based on nuclear sequence data2013In: Taxon, ISSN 0040-0262, E-ISSN 1996-8175, Vol. 63, p. 746-770Article in journal (Refereed)
    Abstract [en]

    Generic limits within subfamily Chrysophylloideae (Sapotaceae) from Oceania and Southeast Asia are reconciled based on a molecular phylogeny. We analysed sequences of nuclear ribosomal DNA (ETS, ITS) and the nuclear gene RPB2 with BEAST and parsimony jackknifing, using a sample of 168 terminals. Eight morphological characters were traced on a condensed majority-rule consensus tree to identify diagnostic character combinations for the genera. Accepted genera with character support are Magodendron, Pichonia, Planchonella, Pycnandra, Sersalisia, and Van-royena, while Beccariella and Niemeyera require amendment. Beccariella, a widely distributed group, is an illegitimate later homonym and we propose that the genus Pleioluma is resurrected in its place. The Australian genus Niemeyera is paraphyletic, but it is rendered monophyletic by reinstating Amorphospermum for N. antiloga. Beauvisagea, Blabeia, Fontbrunea, and Krausella are all segregates of Planchonella and rejected, while Wokoia is a later synonym of Pichonia. Planchonella baillonii, an endemic species of New Caledonia, is the sole member of an old lineage and firmly placed as the sister to a clade comprising the other congeners. Planchonella sandwicensis, a Hawaiian species, previously proposed to be a distinct genus, is a member of Planchonella. In the Pacific, P. tahitensis (including P. grayana) is a polymorphic species, widely distributed and adapted to a wide range of habitats. We provide a generic key (excluding Xantolis), diagnostic character combinations for all genera, and the necessary taxonomic combinations for Pichonia, Planchonella, Pleioluma, and Sersalisia to render each genus monophyletic.

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    Swenson et al. 2013
  • 2052.
    Swenson, Ulf
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Ulfsson, Vigge
    Insektslokalen: Gredelby hagar och Trunsta träsk2018In: Yrfän, ISSN 2002-1151, no 4, p. 6-7Article in journal (Other (popular science, discussion, etc.))
  • 2053.
    Swenson, Ulf
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Ulfsson, Vigge
    Havran, Christopher
    Hawaiiöarna - en flora på fallrepet2016In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 110, no 2, p. 80-107Article in journal (Refereed)
  • 2054.
    Szpryngiel, Scarlett
    Swedish Museum of Natural History, Department of Zoology. Riksantikvarieämbetet.
    Långsprötad silverfisk i museer, bibliotek och arkiv i Sverige2018Report (Other academic)
    Abstract [sv]

    Det finns flera syften med denna rapport. Ett är att klargöra utbredningen av långsprötad silverfisk i Sverige, i såväl privatbostäder som i museer, arkiv och bibliotek. Den långsprötade silverfiskens biologi redogörs det också för i detalj utifrån befintlig litteratur. Dels för att synliggöra potentiella angreppspunkter för framtida bekämpningsåtgärder, dels för att utforma en biologiskt understödd riskbedömning för verksamheter som arbetar med samlingar och arkiv. Väldigt knapphändig information har tidigare funnits för beskrivning av typiska silverfiskskador i samlingar och arkiv. Dokumentationen i denna rapport bidrar därför till en ökad förståelse kring hur svårupptäckta skadorna kan vara och synliggör potentiella risker med att angrepp lämnas utan åtgärd. Ytterligare frågeställningar som berörs gäller artens fenologi i Sverige, dess fortsatta spridning samt skadepotential.

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    silverfiskrapport
  • 2055.
    Szpryngiel, Scarlett
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Coulianos, Carl-Cedric
    Några för Sverige nya ängsskinnbaggar (Hemiptera-Heteroptera: Miridae) jämte nya landskapsfynd2017In: Entomologisk Tidskrift, ISSN 0013-886X, Vol. 138, no 3-4, p. 171-177Article in journal (Refereed)
    Abstract [en]

    Plant bugs (Hemiptera-Heteroptera: Miridae) are terrestrial insects displaying large diversity in both morphology and biology. Here we report four plant bug species new to Sweden, with an overview of known Swedish records and biological and distributional notes. Hence, the Swedish plant bug fauna is now represented by 237 species. Two monophagous bugs are reported: Tupiocoris rhododendri (Dolling, 1772), on cultivated Rhododendron bushes over large parts of southern Sweden and Dichrooscytus gustavi Josifov, 1981, on Juniperus in three localities. The distinctive bug Reuteria marqueti (Puton, 1875) is noted in Gothenburg and Stockholm. All Swedish records of Psallus montanus Josifov, 1973 earlier regarded as P. betuleti are here revised, and P. montanus is shown to have a distribution more centered to the southern parts of Sweden. In addition, we report new provincial records of 26 Swedish plant bug species.

  • 2056. Tan, David J.X.
    et al.
    Chattopadhyay, Balaji
    Garg, Kritika
    Cros, Emilie
    Ericson, Per G P
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Irestedt, Martin
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Rheindt, Frank E.
    Novel genome and genome-wide SNPs reveal early fragmentation effects in an edge-tolerant songbird population across an urbanized tropical metropolis2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, article id 12804Article in journal (Refereed)
    Abstract [en]

    Although edge-tolerant species are known to benefit from habitat fragmentation, less is known about the population genetic impacts fragmentation may exert on edge-tolerant species. We examined the landscape genomic structure of an edge-tolerant forest-dependent bird species, the Striped Tit-Babbler Mixornis gularis, in the heavily urbanized island of Singapore to determine if two centuries of fragmentation have led to signs of isolation and loss of population-genetic diversity in different parts of the island. We obtained a high-quality complete reference genome with 78x coverage. Using almost 4000 SNPs from double-digest RAD-Sequencing across 46 individuals, we found that the population has likely experienced a recent contraction in effective population size and presently exhibits low population genetic diversity. Using empirical and simulation-based landscape genomic analyses, we also found that the subtle population genetic structure observed in the Striped Tit-Babbler population in Singapore is likely driven by isolation by distance resulting from limited dispersal. Our results demonstrate that population genetic impoverishment and subdivision can accumulate at relatively rapid rates in edge-tolerant bird species such as the Striped Tit-Babbler as a result of fragmentation, and that subtle spatial genetic structure can be detected over fine spatial and temporal scales using relatively few multilocus genomic SNPs.

  • 2057. Tandingan De Ley, Irma
    et al.
    Holovachov, Oleksandr
    Swedish Museum of Natural History, Department of Zoology.
    Mc Donnel, Rory J.
    Bert, Wim
    Paine, Tomothy D.
    De Ley, Paul
    Description of Phasmarhabditis californica n. sp. and first report of P. papillosa (Nematoda: Rhabditidae) from invasive slugs in the USA2016In: Nematology (Leiden. Print), ISSN 1388-5545, E-ISSN 1568-5411, Vol. 18, p. 175-193Article in journal (Refereed)
  • 2058. Tang, Feng
    et al.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Wang, Yue
    Wang, Xun-lian
    Yin, Chong-yu
    Eoandromeda and the origin of Ctenophora.2011In: Evolution & Development, ISSN 1520-541X, E-ISSN 1525-142X, Vol. 13, no 5, p. 408-414Article in journal (Refereed)
    Abstract [en]

    The Ediacaran fossil Eoandromeda octobrachiata had a high conical body with eight arms in helicospiral arrangement along the flanks. The arms carried transverse bands proposed to be homologous to ctenophore ctenes (comb plates). Eoandromeda is interpreted as an early stem-group ctenophore, characterized by the synapomorphies ctenes, comb rows, and octoradial symmetry but lacking crown-group synapomorphies such as tentacles, statoliths, polar fields, and biradial symmetry. It probably had a pelagic mode of life. The early appearance in the fossil record of octoradial ctenophores is most consistent with the Planulozoa hypothesis (Ctenophora is the sister group of Cnidaria + Bilateria) of metazoan phylogeny.

  • 2059. Tang, Li
    et al.
    Hu, Xin-Kai
    Santosh, M
    Zhang, Shou-Ting
    Spencer, Christopher J
    Jeon, Heejin
    Zhao, Yu
    Cao, Hua-Wen
    Multistage processes linked to tectonic transition in the genesis of orogenic gold deposit: A case study from the Shanggong lode deposit, East Qinling, China2019In: Ore Geology Reviews, Vol. 111Article in journal (Refereed)
  • 2060.
    Tassia, Michael
    et al.
    Auburn University.
    Cannon, Johanna
    Swedish Museum of Natural History, Department of Zoology. Auburn University.
    Konikoff, Charlotte
    University of Washington.
    Shenkar, Noa
    University of Washington.
    Halanych, Kenneth
    Auburn University.
    Swalla, Billie
    The Global Diversity of Hemichordata2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 10, article id e0162564Article in journal (Refereed)
    Abstract [en]

    Phylum Hemichordata, composed of worm-like Enteropneusta and colonial Pterobranchia, has been reported to only contain about 100 species. However, recent studies of hemichordate phylogeny and taxonomy suggest the species number has been largely underestimated. One issue is that species must be described by experts, and historically few taxonomists have studied this group of marine invertebrates. Despite this previous lack of coverage, interest in hemichordates has piqued in the past couple of decades, as they are critical to understanding the evolution of chordates–as acorn worms likely resemble the deuterostome ancestor more closely than any other extant animal. This review provides an overview of our current knowledge of hemichordates, focusing specifically on their global biodiversity, geographic distribution, and taxonomy. Using information available in the World Register of Marine Species and published literature, we assembled a list of 130 described, extant species. The majority (83%) of these species are enteropneusts, and more taxonomic descriptions are forthcoming. Ptychoderidae contained the greatest number of species (41 species), closely followed by Harrimaniidae (40 species), of the recognized hemichordate families. Hemichordates are found throughout the world’s oceans, with the highest reported numbers by regions with marine labs and diligent taxonomic efforts (e.g. North Pacific and North Atlantic). Pterobranchs are abundant in Antarctica, but have also been found at lower latitudes. We consider this a baseline report and expect new species of Hemichordata will continue to be discovered and described as new marine habitats are characterized and explored.

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    fulltext
  • 2061. Taylor, Charlotte
    et al.
    Razafimandimbison, Sylvain
    Swedish Museum of Natural History, Department of Botany.
    Barrabé, Laure
    Jardim, Jomar G.
    Barbosa, Maria Regina V.
    Eumachia expanded, a tropical genus distinct from Psychotria (Rubiaceae, Palicoureeae)2017In: Candollea, ISSN 0373-2967, E-ISSN 2235-3658, Vol. 72, p. 289-318Article in journal (Refereed)
    Abstract [en]

    The pantropical genus Margaritopsis C. Wright (Rubiaceae, Palicoureeae) was recently separated from Psychotria L. and transferred to a different tribe, Palicoureeae, based on both molecular and morphological data. Margaritopsis has been studied in the Neotropics, and in Africa as Chazaliella E.M.A. Petit & Verdc. ; the species that belong to this group in the Pacific are enumerated for the first time here. Recently Eumachia DC. was found to be an older name for this group, and a few species of Margaritopsis have been transferred nomenclaturally to that genus. Here Eumachia is surveyed comprehensively for the first time, with a list of species and an overview of morphological characteristics. The remaining species of Margaritopsis are nomenclaturally transferred here to Eumachia, along with one species of Hodgkinsonia F. Müll., one species of Mapouria Aubl., and several species of Psychotria from Asia, Australia, New Guinea, and the Pacific region. In this new circumscription Eumachia includes 83 species, and is characterized within Palicoureeae by a yellowish green drying color ; stipules that are persistent or fall by fragmentation and are generally glandular when young and hardened when old ; green to whitened inflorescence axes ; white to cream or yellowish green, often rather small corollas ; orange to red fruits ; pyrenes with marginal pre-formed germination slits and no ethanol-soluble pigments ; and non-ruminate endosperm. Eumachia includes 20 species, 8 subspecies, and 7 varieties in Africa, 27 species in the Neotropics, and 36 species and 6 varieties in Asia, Australasia, and the Pacific region. Here we publish 81 new nomenclatural combinations in Eumachia and two new synonymies for Neotropical names, and 11 names from various regions are lectotypified.

  • 2062.
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany. anders.tehler@nrm.se.
    Four new species of Arthothelium (Arthoniales, Ascomycetes) from Africa and Socotra2017In: Phytotaxa, ISSN ISSN 1179-3155, Vol. 331, no 1, p. 51-64Article in journal (Refereed)
    Abstract [en]

    Four species of Arthothelium from Africa and Socotra are described as new to science: Arthothelium atrorubrum from Mada- gascar, characterized by irregularly rounded blackish ascomata with a deeply red hypothecium and submuriform ascospores; Arthothelium aurantiacopruinosum from the Democratic Republic of the Congo, characterized by black, irregularly rounded to stellate, orange pruinose ascomata and muriform ascospores with two larger terminal cells; Arthothelium frischianum from Madagascar, characterized by brownish-black minute irregular ascomata with remnants of thallus and muriform asco- spores with one larger terminal cell; Arthothelium miesii from Socotra (Yemen), characterized by a thick thallus, immersed, stellate to cerebriform, brownish, greyish pruinose ascomata and submuriform ascospores. A key to all reported species of Arthothelium from tropical Africa (South Africa excluded) and Socotra is provided. 

  • 2063.
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany.
    The genera Dirina and Roccellina (Roccellaceae)1983In: Opera Botanica, Vol. 70, p. 1-86Article in journal (Refereed)
  • 2064.
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany.
    The species pair concept in lichenology1982In: Taxon, Vol. 31, p. 708-714Article in journal (Refereed)
  • 2065.
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany. anders.tehler@nrm.se.
    Three new combinations in the genus Fulvophyton (Roccellographaceae, Arthoniales)2017In: The Lichenologist, ISSN 0024-2829, E-ISSN 1096-1135, Vol. 49, p. 171-173Article in journal (Refereed)
  • 2066.
    Tehler, Anders
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Diederich, Paul
    Ertz, Damien
    Proposal to reject the nameLichen conspurcatus(Roccellaceae)2013In: Taxon, Vol. 62, no 6, p. 1334-1335Article in journal (Refereed)
  • 2067.
    Tehler, Anders
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Ertz, Damien
    Irestedt, Martin
    The genus Dirina (Roccellaceae, Arthoniales) revisited2013In: Lichenologist, Vol. 45, no 4, p. 427-476Article in journal (Refereed)
  • 2068.
    Tehler, Anders
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Irestedt, Martin
    Ertz, Damien
    Austroroccella, a new fruticose genus in the family Roccellaceae2013In: Bryologist, Vol. 116, no 2, p. 162-168Article in journal (Refereed)
  • 2069.
    Tehler, Anders
    et al.
    Swedish Museum of Natural History, Department of Botany. anders.tehler@nrm.se.
    Sodamuk, Mattika
    Boonpragob, Kansri
    Mongkolsuk, Pachara
    Leavitt, Steven
    Lumbsch, Thorsten
    Kalbionora palaeotropica , a new genus and species from coastal forests in Southeast Asia and Australia (Malmideaceae, Ascomycota)2017In: MycoKeys, Vol. 22, p. 15-25Article in journal (Refereed)
  • 2070.
    Tehler, Anders
    et al.
    Swedish Museum of Natural History, Department of Botany.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Systematics, phylogeny and classification2008In: Lichen Biology, 2nd edition, Cambridge: Cambridge University Press , 2008Chapter in book (Refereed)
  • 2071. Terra-Araujo, Mario
    et al.
    de Faria, Aparecida
    Vicentini, Alberto
    Nylinder, Nylinder
    Swedish Museum of Natural History, Department of Botany.
    Swenson, Ulf
    Swedish Museum of Natural History, Department of Botany.
    Species tree phylogeny and biogeography of the Neotropical genus Pradosia (Sapotaceae, Chrysophylloideae).2015In: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 87, p. 1-13Article in journal (Refereed)
    Abstract [en]

    Recent phylogenetic studies in Sapotaceae have demonstrated that many genera need to be redefined to better correspond to natural groups. The Neotropical genus Pradosia is believed to be monophyletic and includes 26 recognized species. Here we reconstruct the generic phylogeny by a species-tree approach using ∗BEAST, 21 recognized species (36 accessions), sequence data from three nuclear markers (ITS, ETS, and RPB2), a relaxed lognormal clock model, and a fossil calibration. We explore the evolution of five selected morphological characters, reconstruct the evolution of habitat (white-sand vs. clayish soils) preference, as well as space and time by using a recently developed continuous diffusion model in biogeography. We find Pradosia to be monophyletic in its current circumscription and to have originated in the Amazon basin at ∼ 47.5 Ma. Selected morphological characters are useful to readily distinguish three clades. Preferences to white-sand and/or clay are somewhat important for the majority of species, but speciation has not been powered by habitat shifts. Pradosia brevipes is a relative young species (∼ 1.3 Ma) that has evolved a unique geoxylic life strategy within Pradosia and is restricted to savannahs. Molecular dating and phylogenetic pattern indicate that Pradosia reached the Brazilian Atlantic coast at least three times: at 34.4 Ma (P. longipedicellata), at 11.7 Ma (P. kuhlmannii), and at 3.9 Ma (weakly supported node within the red-flowered clade).

  • 2072. Terra-Araujo, Mário H.
    et al.
    de Faria, Aparecida D.
    Swenson, Ulf
    Swedish Museum of Natural History, Department of Botany.
    A taxonomic update of Neotropical Pradosia (Sapotaceae, Chrysophylloideae)2016In: Systematic Botany, ISSN 0363-6445, E-ISSN 1548-2324, Vol. 41, p. 634-650Article in journal (Refereed)
    Abstract [en]

    We provide a systematic update of Pradosia (Sapotaceae, Chrysophylloideae), including overall morphology, a key to all species, comprehensive morphological descriptions, geographic distributions, and important characteristics for each species. Phyloge- netic analyses based on molecular data demonstrated that the genus is monophyletic and includes three main clades. Twenty-three species of Pradosia are accepted, which are mostly distributed in lowland rainforests on either white-sand or clayish soils in tropical South America. A rotate corolla with a short tube, lack of staminodes, a drupaceous fruit with plano-convex cotyledons, an exserted radicle below the cotyledons, and the absence of endosperm are diagnostic for the genus. Two names are reduced into synonymy, viz. Pradosia atroviolacea Ducke, syn. of P. grisebachii (Pierre) T. D. Penn., and Pradosia verrucosa Ducke, syn. of P. glaziovii (Pierre) T. D. Penn. The affinity of P. argentea (Kunth) T. D. Penn., a species known only from the type collection, remains uncertain and for now excluded from the genus.

  • 2073.
    Tewari, Rajni
    et al.
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Ram- Awatar, Ram-
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Pandita, Sundeep
    Department of Geology, University of Jammu, Jammu-180006, India.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Agnihotri, Deepa
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Pillai, Suresh
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Singh, Vartika
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Kumar, Kamlesh
    Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, India.
    Bhat, Ghulam
    Directorate of Geology and Mining, Jammu and Kashmir Government, Srinagar, India.
    The Permian-Triassic palynological transition in the Guryul Ravine section, Kashmir, India: implications for Tethyan – Gondwanan correlations2015In: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 149, p. 53-66Article in journal (Refereed)
    Abstract [en]

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

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    fulltext
  • 2074.
    Thell, Arne
    et al.
    Lund University.
    Alstrup, Vagn
    Arup, Ulf
    Lund University.
    Bendiksby, Mika
    Czarnota, Pavel
    Feuerer, Tassilo
    Haugan, Reidar
    Kärnefelt, Ingvar
    Lund University.
    Klepsland, Jon
    Kukwa, Martin
    Launis, Annina
    Millanes, Ana
    Universidad Rey Juan Carlso.
    Motiejunaite, Jurga
    Nordin, Anders
    Uppsala University.
    Prieto, Maria
    Swedish Museum of Natural History, Department of Botany.
    Pykälä, Juha
    Seaward, Mark
    Timdal, Einar
    Tsurykau, Andrei
    Vitikainen, Orvo
    Westberg, Martin
    Swedish Museum of Natural History, Department of Botany.
    New or interesting lichens and lichenicolous fungi from the Vadstena area, Östergötland, Sweden2014In: Graphis Scripta, ISSN 0901-7593, Vol. 26, no 1-2, p. 15-33Article in journal (Refereed)
  • 2075.
    Thiessen, Fiona
    Swedish Museum of Natural History, Department of Geology. Department of Geological Sciences, Stockholm University, SE-106 91, Stockholm, Sweden.
    Snape, Joshua
    Faculty of Earth and Life Sciences, VU Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, the Netherlands.
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology. Department of Geological Sciences, Stockholm University, SE-106 91, Stockholm, Sweden.
    U-Pb SIMS ages of Apollo 14 zircon: Identifying distinct magmatic episodes2019In: Meteoritics and Planetary Science, ISSN 1086-9379, E-ISSN 1945-5100, Vol. 54, p. 1720-1736Article in journal (Refereed)
  • 2076.
    Thiessen, Fiona
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Nemchin, Alexander
    Curtin University, Perth, Australia.
    Snape, Joshua
    Swedish Museum of Natural History, Department of Geology.
    Bellucci, Jeremy
    Swedish Museum of Natural History, Department of Geology.
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology. Stockholm University, Department of Geological Sciences.
    Apollo 12 breccia 12013: Impact-induced partial Pb loss inzircon and its implications for lunar geochronology2018In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 230, p. 94-111Article in journal (Refereed)
    Abstract [en]

    Apollo 12 breccia 12013 is composed of two portions, one grey in colour, the other black. The grey portion of the brecciaconsists mainly of felsite thought to have formed during a single crystallisation event, while the black part is characterized bypresence of lithic fragments of noritic rocks and individual plagioclase crystals. In this study, U-Pb analyses of Ca-phosphateand zircon grains were conducted in both portions of the breccia. The zircon grains within the grey portion yielded a largerange of ages (4154 ± 7 to 4308 ± 6 Ma, 2r) and show decreasing U and Th concentrations within the younger grains. Moreover,some grains exhibit recrystallisation features and potentially formation of neoblasts. The latter process requires hightemperatures above 1600–1700 C leading to the decomposition of the primary zircon grain and subsequent formation ofnew zircon occurring as neoblasts. As a result of the high temperatures, the U-Pb system of the remaining original zircongrains was most likely open for Pb diffusion causing partial resetting and the observed range of 207Pb/206Pb ages. The eventthat led to the Pb loss in zircon could potentially be dated by the U-Pb system in Ca-phosphates, which have a weighted average207Pb/206Pb age across both lithologies of 3924 ± 3 Ma (95% conf.). This age is identical within error to the combinedaverage 207Pb/206Pb age of 3926 ± 2 Ma that was previously obtained from Ca-phosphates within Apollo 14 breccias, zircongrains in Apollo 12 impact melt breccias, and the lunar meteorite SaU 169. This age was interpreted to date the Imbriumimpact. The zircon grains located within the black portion of the breccia yielded a similar range of ages (4123 ± 13 to4328 ± 14 Ma, 2r) to those in the grey portion. Given the brecciated nature of this part of the sample, the interpretationof these ages as representing igneous crystallisation or resetting by impact events remains ambiguous since there is no directlink to their source rocks via textural relationships or crystal chemistry. Similarly, the currently available zircon data set for alllunar samples may be distorted by partial Pb loss, resulting in meaningless and misleading age distribution patterns. Therefore,it is crucial to fully understand and recognize the processes and conditions that may lead to partial resetting of the U-Pbsystem in zircon in order to better constrain the magmatic and impact history of the Moon.

  • 2077.
    Thiessen, Fiona
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Nemchin, Alexander
    Curtin University.
    Snape, Joshua
    Swedish Museum of Natural History, Department of Geology.
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Bellucci, Jeremy
    Swedish Museum of Natural History, Department of Geology.
    Impact history of the Apollo 17 landing site revealed by U-Pb SIMS ages2017In: Meteoritics and Planetary Science, ISSN 1086-9379, E-ISSN 1945-5100, Vol. 52, no 4, p. 584-611Article in journal (Refereed)
    Abstract [en]

    Secondary ion mass spectrometry (SIMS) U-Pb ages of Ca-phosphates from four texturally distinct breccia samples (72255, 76055, 76015, 76215) collected at the Apollo 17 landing site were obtained in an attempt to identify whether they represent a single or several impact event(s). The determined ages, combined with inferences from petrologic relationships, may indicate two or possibly three different impact events at 3920±3 Ma, 3922±5 Ma and 3930±5 Ma (all errors 2σ). Searching for possible sources of the breccias by calculating the continuous ejecta radii of impact basins and large craters as well as their expected ejecta thicknesses, we conclude that Nectaris, Crisium, Serenitatis and Imbrium are likely candidates. If the previous interpretation that the micropoikilitic breccias collected at the North Massif represent Serenitatis ejecta is correct, then the average 207Pb/206Pb age of 3930±5 Ma (2σ) dates the formation of the Serenitatis basin. The occurrence of zircon in the breccias sampled at the South Massif, which contain Ca-phosphates yielding an age of 3922±5 Ma (2σ), may indicate that the breccia originated from within the Procellarum KREEP terrane (PKT) and the Imbrium basin appears to be the only basin that could have sourced them. However, this interpretation implies that all basins suggested to fall stratigraphically between Serenitatis and Imbrium formed within a short (<11 Ma) time interval, highlighting serious contradictions between global stratigraphic constraints, sample interpretation and chronological data. Alternatively, the slightly older age of the two micropoikilitic breccias may be a result of incomplete resetting of the U-Pb system preserved in some phosphate grains. Based on the currently available dataset this possibility cannot be excluded.

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    Impact history Apollo 17
  • 2078.
    Thornton, Brett
    et al.
    Department of Environmental Sciences and Analytical Chemistry, Stockholm University.
    Horst, Axel
    Department of Environmental Sciences and Analytical Chemistry, Stockholm University.
    Carrizo, Daniel
    Department of Environmental Sciences and Analytical Chemistry, Stockholm University.
    Holmstrand, Henry
    Department of Environmental Sciences and Analytical Chemistry, Stockholm University.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    Crill, Patrick
    Department of Geological Sciences, Stockholm University.
    Gustafsson, Örjan
    Department of Environmental Sciences and Analytical Chemistry, Stockholm University.
    A High-Volume Cryosampler and Sample Purification System for Bromine Isotope Studies of Methyl Bromide2013In: Journal of Atmospheric and Oceanic Technology, ISSN 0739-0572, E-ISSN 1520-0426, ISSN 0739-0572, Vol. 30, no 9, p. 2095-2107Article in journal (Refereed)
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  • 2079. Thulin, Mats
    et al.
    Razafimandimbison, Sylvain
    Swedish Museum of Natural History, Department of Botany.
    Bourreria scabra (Boraginaceae), a new species from southern Madagascar2017In: Candollea, ISSN 0373-2967, E-ISSN 2235-3658, Vol. 72, no 2, p. 345-350Article in journal (Refereed)
    Abstract [en]

     Bourreria scabra Thulin & Razafim.  (Boraginaceae), a new species from southern Madagascar, is described and illustrated. The plant was previously sometimes treated as conspecific with  Bourreria lyciacea Thulin [[  Hilsenbergia lyciacea (Thulin) J.S. Mill.] in Somalia and Kenya. However,  Bourreria scabra differs markedly from  Bourreria lyciacea by its smaller corolla, finely pubescent outside and with shorter lobes, by its practically unbranched style, by its smaller fruits more or less enclosed by the calyx, and by its smaller pyrenes with several low ridges forming an irregular reticulation on the outside. Bourreria scabra differs from all other species of  Bourreria P. Browne in Madagascar by the very rough upper surface of the leaves. The species is widespread in spiny dry forests in southern Madagascar, with occurrences in the Andohahela and Tsimanampetsotsa National Parks and the Beza Mahafaly Reserve. The new species is assigned the category of “Near Threatened” using the IUCN Red List Criteria.

  • 2080.
    Thulin, Mats
    et al.
    Systematic Biology, Department of Organismal Biology, EBC, Uppsala University, Norbyvägen 18D, SE-752 36 Uppsala, Sweden.
    Razafimandimbison, Sylvain
    Swedish Museum of Natural History, Department of Botany.
    Ormocarpopsis anosyana Thulin & Razafim. (Fabaceae), a new species from southern Madagascar and its phylogenetic position2016In: Candollea, ISSN 0373-2967, Vol. 71, no 2, p. 281-286Article in journal (Refereed)
    Abstract [en]

    Ormocarpopsis anosyana Thulin & Razafim. (Fabaceae), a new species from the Anosy Region of south-eastern Madagascar, is described and illustrated. According to phylogenetic analyses based on nuclear ribosomal ITS sequences, the new species is, with strong support, sister to Ormocarpopsis mandrarensis Dumaz-le-Grand, another species confined to southeastern Madagascar. Ormocarpopsis anosyana differs markedly from Ormocarpopsis mandrarensis by its generally smaller leaflets with the secondary and tertiary venation drying more or less blackish beneath, by its shorter hypanthium, by its smaller calyx with the lowest tooth about as long as the others, by its wing-petals that are much longer than the keel, by its glabrous ovary, and by its slightly articulated fruits. Ormocarpopsis anosyana is known only from two collections from a single patch of spiny dry forest east of Imonty. It is assigned a preliminary conservation status as “Endangered”.

  • 2081. Thunes, Karl H.
    et al.
    Skartveit, J.
    Gjerde, I.
    Solhöy, T.
    Fjellberg, A
    Kobro, S.
    Nakahara, S.
    zur Strassen, R.
    Vierbergen, G.
    Szadziewski, R.
    Hagan, D. V.
    Grogan Jr., W. L.
    Jonassen, T.
    Aakra, K.
    Anonby, J.
    Greve, L.
    Aukema, B.
    Heller, K.
    Michelsen, V.
    Haenni, J.-P.
    Emeljanov, A. F.
    Douwes, P.
    Berggren, K.
    Franzen, J.
    Disney, R. H. L.
    Prescher, S.
    Johanson, Kjell Arne
    Swedish Museum of Natural History, Department of Zoology.
    Mamaev, B.
    Podenas, S.
    Andersen, S.
    Gaimari, S. D.
    Nartshuk, E.
    Söli, G. E. E.
    Midtgaard, F.
    Andersen, A.
    von Tschirnhaus, M.
    Bächli, G.
    Olsen, K. M.
    Olsvik, H.
    Földvári, M.
    Raastad, J. E.
    Hansen, L. O.
    Djursvoll, P.
    The arthropod community of Scots pine (Pinus sylvestris L.) canopies in Norway2004In: Entomologica Fennica, ISSN 0785-8760, Vol. 15, p. 65-90Article in journal (Refereed)
  • 2082. Thureborn, Olle
    et al.
    Razafimandimbison, Sylvain Georges
    Swedish Museum of Natural History, Department of Botany.
    Wikström, Niklas
    Khodabandeh, Anbar
    Rydin, Catarina
    Phylogeny of Anthospermeae of the coffee family inferred using clock and nonclock models2019In: International Journal of Plant Sciences, Vol. 180, no 5, p. 386-402Article in journal (Refereed)
    Abstract [en]

    Premise of research. With wind-pollinated flowers and partly temperate distribution, the tribe Anthospermeae stands out in the otherwise mostly animal-pollinated and tropical coffee family (Rubiaceae). Nevertheless, few attempts to resolve the phylogeny of the group have been made, and inter- and infrageneric relationships have been only partly addressed. Here we investigate evolutionary relationships and generic and subtribal delimitations of Anthospermeae. We assess the influence of alternative evolutionary rate models on topology and node support.

    Methodology. Using sequence data from the nuclear (nrITS and nrETS) and plastid (atpB-rbcLndhFrbcLrps16, and trnT-trnF) genomes collected for a broad sample of taxa, we conducted Bayesian analyses using nonclock, strict clock, and relaxed clock models. The resulting topologies and support values were compared, and the relative fit of evolutionary models to our data was evaluated. Marginal likelihood estimates were used to discriminate between the competing rate models.

    Pivotal results. The monophyly of Anthospermeae was confirmed with Carpacoceresolved as sister to the remaining species. We found several cases of supported topological conflict between results based on nuclear and plastid data, but the deepest splits of the tribe were congruent among all analyses and incompatible with traditional subtribal delimitations of Anthospermeae. Monophyly of the genera AnthospermumNenax, and Coprosma was not supported. While the relaxed clock model was consistently favored over the nonclock and strict clock models for all data sets, the use of the different models had little impact on phylogenetic results.

    Conclusions. We propose a revised subtribal classification of Anthospermeae, including a new subtribe, the monogeneric Carpacocinae. Introgression/hybridization and incomplete lineage sorting are the most likely causes for the plastid-nuclear incongruences detected for Anthospermeae, but their relative contribution could not be concluded.

  • 2083.
    Thuy, Ben
    et al.
    Geoscience Centre, University of Göttingen.
    Gale, Andrew
    University of Portsmouth.
    Stöhr, Sabine
    Swedish Museum of Natural History, Department of Zoology.
    Wiese, Frank
    Geoscience Centre, Göttingen.
    Shallow-water brittle-star (Echinodermata: Ophiuroidea) assemblages from the Aptian (Early Cretaceous) of the North Atlantic: first insights into bathymetric distribution patterns2014In: Göttingen Contributions to Geosciences, ISSN ISSN 2199-1324, Vol. 77, p. 163-182-Article in journal (Refereed)
  • 2084.
    Thuy, Ben
    et al.
    Geoscience Centre, University of Göttingen.
    Kiel, Steffen
    Geoscience Center, Göttingen.
    Dulai, Alfred
    Gale, Andy S.
    University of Portsmouth, UK.
    Kroh, Andreas
    Natural History Museum, Vienna.
    Lord, Alan S.
    Numberger-Thuy, Lea
    Stöhr, Sabine
    Swedish Museum of Natural History, Department of Zoology.
    Wisshak, Max
    First glimpse into Lower Jurassic deep-sea biodiversity: in situ diversification and resilience against extinction2014In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 281, article id 20132624Article in journal (Refereed)
  • 2085. Thuy, Ben
    et al.
    Stöhr, Sabine
    Swedish Museum of Natural History, Department of Zoology.
    A New Morphological Phylogeny of the Ophiuroidea (Echinodermata) Accords with Molecular Evidence and Renders Microfossils Accessible for Cladistics2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 5, p. e0156140-Article in journal (Refereed)
  • 2086. Thuy, Ben
    et al.
    Stöhr, Sabine
    Swedish Museum of Natural History, Department of Zoology.
    Unravelling the origin of the basket stars and their allies (Echinodermata, Ophiuroidea, Euryalida).2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, no 1, article id 8493Article in journal (Refereed)
    Abstract [en]

    Euryalids, which include the spectacular basket stars, form a morphologically aberrant group of brittle stars. Surprisingly, the most recent molecular work found them to be sister to ophiurid brittle stars, thus challenging the traditional dichotomy between euryalids and non-euryalids, and leaving an enormous ghost lineage of more than 100 million years between the oldest unambiguous euryalid fossils and their predicted divergence from ophiurids during the Triassic. Here we examine both previously known and newly collected fossils to explore the evolutionary history of euryalids. A morphology-based phylogenetic estimate confirms the Triassic Aspiduriella as a basal member of the euryalid clade that superficially resembles members of the living ophiurid sister clades. Furthermore, we use lateral arm plates and vertebrae to identify two new Jurassic ophiuroids, Melusinaster alissawhitegluzae and Melusinaster arcusinimicus, as early euryalids that are morphologically intermediate between Aspiduriella and extant euryalids. Our phylogenetic analysis is the first to combine data from completely preserved skeletons and from microfossils in order to bridge morphological and stratigraphical gaps between the sampled taxa. It fills a major gap in the fossil record of euryalids and sets a robust phylogenetic framework to understand the morphological transition from ophiurid-like ancestors to the typical modern euryalids better.

  • 2087. Tichomirowa, Marion
    et al.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Gerdes, Axel
    Schulz, Bernhard
    Zircon (Hf, O isotopes) as melt indicator: Melt infiltration and abundant new zircon growth within melt rich layers of granulite-facies lenses versus solid-state recrystallization in hosting amphibolite-facies gneisses (central Erzgebirge, Bohemian Massif)2018In: Lithos, ISSN 0024-4937, E-ISSN 1872-6143, Vol. 302-303, p. 65-85Article in journal (Refereed)
    Abstract [en]

    In the central Erzgebirge within the Bohemian Massif, lenses of high pressure and ultrahigh pressure felsic granulites occur within meta-sedimentary and meta-igneous amphibolite-facies felsic rocks. In the felsic granulite, melt rich parts and restite form alternating layers, and were identified by petrology and bulk rock geochemistry. Mineral assemblages representing the peak P-T conditions were best preserved in melanocratic restite layers. In contrast, in the melt rich leucocratic layers, garnet and related HP minerals as kyanite are almost completely resorbed. Both layers display differences in accessory minerals: melanosomes have frequent and large monazite and Fe–Ti-minerals but lack xenotime and apatite; leucosomes have abundant apatite and xenotime while monazite is rare. Here we present a detailed petrographic study of zircon grains (abundance, size, morphology, inclusions) in granulite-facies and amphibolite-facies felsic gneisses, along with their oxygen and hafnium isotope compositions. Our data complement earlier UPb ages and trace element data (REE, Y, Hf, U) on zircons from the same rocks (Tichomirowa et al., 2005). Our results show that the degree of melting determines the behaviour of zircon in different layers of the granulites and associated amphibolite-facies rocks. In restite layers of the granulite lenses, small, inherited, and resorbed zircon grains are preserved and new zircon formation is very limited. In contrast, new zircons abundantly grew in the melt rich leucocratic layers. In these layers, the new zircons (UPb age, trace elements, Hf, O isotopes) best preserve the information on peak metamorphic conditions due to intense corrosion of other metamorphic minerals. The new zircons often contain inherited cores. Compared to cores, the new zircons and rims show similar or slightly lower Hf isotope values, slightly higher Hf model ages, and decreased oxygen isotope ratios. The isotope compositions (Hf, O) of new zircons indicate partial Hf isotope homogenization in the melt, and melt infiltration from an external source. New zircon was most likely formed by a peritectic reaction with melt above the wet solidus (peritectic zircon). Conversely, the amphibolite-facies host gneisses lack indications of significant melt production. Pre-metamorphic zircons experienced mainly solid-state recrystallization and variable Pb loss with only minor new zircon formation. However, subtle changes in cathodoluminescence pattern, in the Hf and O isotopes, and in the Lu/Hf, Yb/Hf ratios of zircons suggest that small volumes of melt were locally present. In difference to granulites, melt was internally produced. The detection of low degree melts (inferred from zircon geochemistry) is extremely important for the rheology because these amphibolite-facies rocks could act as large scale ductile shear zones. The new zircon data support a different P-T path for closely spaced amphibolite- and granulite-facies rocks.

  • 2088. Tillberg, Mikael
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Drake, Henrik
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Koijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    Schmitt, M
    Re-evaluating the age of deep biosphere fossils in the Lockne impact structure2019In: Geosciences, Vol. 9, no 5, article id 202Article in journal (Refereed)
    Abstract [en]

    Impact-generated hydrothermal systems have been suggested as favourable environments for deep microbial ecosystems on Earth, and possibly beyond. Fossil evidence from a handful of impact craters worldwide have been used to support this notion. However, as always with mineralized remains of microorganisms in crystalline rock, certain time constraints with respect to the ecosystems and their subsequent fossilization are difficult to obtain. Here we re-evaluate previously described fungal fossils from the Lockne crater (458 Ma), Sweden. Based on in-situ Rb/Sr dating of secondary calcite-albite-feldspar (356.6 ± 6.7 Ma) we conclude that the fungal colonization took place at least 100 Myr after the impact event, thus long after the impact-induced hydrothermal activity ceased. We also present microscale stable isotope data of 13C-enriched calcite suggesting the presence of methanogens contemporary with the fungi. Thus, the Lockne fungi fossils are not, as previously thought, related to the impact event, but nevertheless have colonized fractures that may have been formed or were reactivated by the impact. Instead, the Lockne fossils show similar features as recent findings of ancient microbial remains elsewhere in the fractured Swedish Precambrian basement and may thus represent a more general feature in this scarcely explored habitat than previously known.

  • 2089. Tillberg, Mikael
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Drake, Henrik
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Kooijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    Schmitt, Melanie
    Swedish Museum of Natural History, Department of Geology.
    Re-Evaluating the Age of Deep Biosphere Fossils in the Lockne Impact Structure2019In: GeosciencesArticle in journal (Refereed)
  • 2090. Tison, Jean-Luc
    et al.
    Edmark, Veronica Nyström
    Sandoval-Castellanos, Edson
    Van Dyck, Hans
    Tammaru, Toomas
    Välimäki, Panu
    Dalén, Love
    Gotthard, Karl
    Signature of post-glacial expansion and genetic structure at the northern range limit of the speckled wood butterfly2014In: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 113, no 1, p. 136-148Article in journal (Refereed)
    Abstract [en]

    The post-glacial recolonisation of northern Europe has left distinct signatures in the genomes of many organisms, both due to random demographic processes and divergent natural selection. However, information on differences in genetic variation in conjunction with patterns of local adaptations along latitudinal gradients is often lacking. In this study, we examine genetic diversity and population structure in the speckled wood butterfly Pararge aegeria in northern Europe to investigate the species post-glacial recolonisation history and discuss how this may have affected its life-history evolution. We collected 209 samples and analysed genetic variation in nine microsatellite loci. The results demonstrated a more pronounced population structure in northern Europe compared with populations further south, as well as an overall decrease in genetic diversity with latitude, likely due to founder effects during the recolonisation process. Coalescent simulations coupled with approximate Bayesian computation suggested that central Scandinavia was colonised from the south, rather than from the east. In contrast to further south, populations at the northern range margin are univoltine expressing only one generation per year. This suggests either that univoltinism evolved independently on each side of the Baltic Sea, or that bivoltinism evolved in the south after northern Europe was recolonised. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113, 136–148.

  • 2091.
    Tison, J-L.
    et al.
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Blennow, V
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Palkopoulou, E
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Gustavsson, P
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Roos, Anna
    Swedish Museum of Natural History, Department of Environmental research and monitoring. Department of Environmental Toxicology, Uppsala Universitet.
    Dalén, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Population structure and recent temporal changes in genetic variation in Eurasian otters from Sweden.2015In: Conservation Genetics, ISSN 1566-0621, E-ISSN 1572-9737, Vol. 16, no 371, article id 384Article in journal (Refereed)
  • 2092.
    Todaro, M. Antonio
    et al.
    Department of Biology, University of Modena and Reggio Emilia, Modena, Italy.
    Dal Zotto, Matteo
    Department of Biology, University of Modena and Reggio Emilia, Modena, Italy.
    Jondelius, Ulf
    Swedish Museum of Natural History, Department of Zoology.
    Hochberg, Rick
    Department of Biology, University of Massachusetts Lowell, Lowell, MA 01854, USA.
    Hummon, William D.
    Department of Biological Sciences,Ohio University, Athens, Ohio, United States of America.
    Kånneby, Tobias
    Swedish Museum of Natural History, Department of Zoology.
    Rocha, Carlos E. F.
    Departamento de Zoologia, Instituto de Biocieˆncias, Universidade de Sa˜o Paulo, Sa˜o Paulo, Brazil.
    Gastrotricha: A Marine Sister for a Freshwater Puzzle2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 2, p. e31740-Article in journal (Refereed)
    Abstract [en]

    Within an evolutionary framework of Gastrotricha Marinellina flagellata and Redudasys fornerise bear special interest, as they are the only Macrodasyida that inhabit freshwater ecosystems. Notwithstanding, these rare animals are poorly known; found only once (Austria and Brazil), they are currently systematised as incertae sedis. Here we report on the rediscovery of Redudasys fornerise, provide an account on morphological novelties and present a hypothesis on its phylogenetic relationship based on molecular data. Specimens were surveyed using DIC microscopy and SEM, and used to obtain the 18 S rRNA gene sequence; molecular data was analyzed cladistically in conjunction with data from 42 additional species belonging to the near complete Macrodasyida taxonomic spectrum. Morphological analysis, while providing new information on taxonomically relevant traits (adhesive tubes, protonephridia and sensorial bristles), failed to detect elements of the male system, thus stressing the parthenogenetic nature of the Brazilian species. Phylogenetic analysis, carried out with ML, MP and Bayesian approaches, yielded topologies with strong nodal support and highly congruent with each other. Among the supported groups is the previously undocumented clade showing the alliance between Redudasys fornerise and Dactylopodola agadasys; other strongly sustained clades include the densely sampled families Thaumastodermatidae and Turbanellidae and most genera. A reconsideration of the morphological traits of Dactylopodola agadasys in light of the new information on Redudasys fornerise makes the alliance between these two taxa very likely. As a result, we create Anandrodasys gen. nov. to contain members of the previously described D. agadasys and erect Redudasyidae fam. nov. to reflect this novel relationship between Anandrodasys and Redudasys. From an ecological perspective, the derived position of Redudasys, which is deeply nested within the Macrodasyida clade, unequivocally demonstrates that invasion of freshwater by gastrotrichs has taken place at least twice, in contrast with the single event hypothesis recently put forward.

  • 2093.
    Todaro, M. Antonio
    et al.
    Department of Biology, University of Modena and Reggio Emilia, Modena, Italy.
    Kånneby, Tobias
    Swedish Museum of Natural History, Department of Zoology.
    Dal Zotto, Matteo
    Department of Biology, University of Modena and Reggio Emilia, Modena, Italy.
    Jondelius, Ulf
    Swedish Museum of Natural History, Department of Zoology.
    Phylogeny of Thaumastodermatidae (Gastrotricha: Macrodasyida) Inferred from Nuclear and Mitochondrial Sequence Data2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 3, p. e17892-Article in journal (Refereed)
    Abstract [en]

    Background: Phylogenetic relationships within Gastrotricha are poorly known. Attempts to shed light on this subject using morphological traits have led to hypotheses lacking satisfactory statistical support; it seemed therefore that a different approach was needed.

    Methodology/Principal Findings: In this paper we attempt to elucidate the relationships within the taxonomically vast family Thaumastodermatidae (Macrodasyida) using molecular sequence data. The study includes representatives of all the extant genera of the family and for the first time uses a multi-gene approach to infer evolutionary liaisons within Gastrotricha. The final data set comprises sequences of three genes (18S, 28S rDNA and COI mtDNA) from 41 species, including 29 thaumastodermatids, 11 non-thaumastodermatid macrodasyidans and a single chaetonotidan. Molecular data was analyzed as a combined set of 3 genes and as individual genes, using Bayesian and maximum likelihood approaches. Two different outgroups were used: Xenotrichula intermedia (Chaetonotida) and members of the putative basal Dactylopodola (Macrodasyida). Thaumastodermatidae and all other sampled macrodasyidan families were found monophyletic except for Cephalodasyidae. Within Thaumastodermatidae Diplodasyinae and Thaumastodermatinae are monophyletic and so are most genera. Oregodasys turns out to be the most basal group within Thaumastodermatinae in analyses of the concatenated data set as well as in analyses of the nuclear genes. Thaumastoderma appears as the sister taxon to the remaining species. Surprisingly, Tetranchyroderma is non-monophyletic in our analyses as one group of species clusters with Ptychostomella while another appears as the sister group of Pseudostomella.

    Conclusions/Significance: Results in general agree with the current classification; however, a revision of the more derived thaumastodermatid taxa seems necessary. We also found that the ostensible COI sequences from several species do not conform to the general invertebrate or any other published mitochondrial genetic code; they may be mitochondrially derived nuclear genes (numts), or one or more modifications of the mitochondrial genetic code within Gastrotricha.

  • 2094. Toljander, Jonas F.
    et al.
    Santos, Juan C
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany. anders.tehler@nrm.se.
    Finlay, Roger D
    Community analysis of arbuscular mycorrhizal fungi and bacteria in the maize mycorrhizosphere in a long-term fertilisation trial2008In: FEMS Microbiology Ecology, Vol. 65, p. 323-338Article in journal (Refereed)
  • 2095.
    Topper, Timothy P.
    Geological Museum, Copenhagen.
    Peel, John S.
    Uppsala Universitet.
    Harper, David A.T.
    Durham University.
    Moulting in the lobopodian Onychodictyon from the lower Cambrian of Greenland2013In: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 46, no 4, p. 490-495Article in journal (Refereed)
    Abstract [en]

    A number of lobopodian taxa from the Cambrian display pairs of sclerotized plates symmetrically positioned along the dorsum of the animal, predominantly above the walking appendages. Most genera were described from complete body fossils exquisitely preserved in the famous Cambrian Lagerstätten, but lobopodian phosphatized plates are found worldwide as typical components of Cambrian small shelly fossil assemblages (SSF). Details regarding intraspecific and ontogenetic variation in lobopod plates are elusive, and the lack of details of ornamentation in Lagerstätte specimens does not minimize the problem. We document here an assemblage of well-preserved isolated plates of Onychodictyon sp. from the Lower Cambrian (Cambrian Series 2, Stage 4) of North Greenland. Two specimens exhibit perfectly conjoined plates from successive moults. Details of ornamentation and the outline and profile of the fixed plates are identical, but width and length of the underlying plate are 24% larger. These specimens boost the body of evidence that lobopodians moulted but also show that plate outline and ornamentation did not vary during ontogeny.

  • 2096. Topper, Timothy, P.
    et al.
    Guo, Junfeng
    Clausen, Sébastien
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Zhang, Zhifei
    A stem group echinoderm from the basal Cambrian of China and the origins of Ambulacraria2019In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 10, article id 1366Article in journal (Refereed)
    Abstract [en]

    Deuterostomes are a morphologically disparate clade, encompassing the chordates (including vertebrates), the hemichordates (the vermiform enteropneusts and the colonial tube-dwelling pterobranchs) and the echinoderms (including starfish). Although deuterostomes are considered monophyletic, the inter-relationships between the three clades remain highly contentious. Here we report, Yanjiahella biscarpa, a bilaterally symmetrical, solitary metazoan from the early Cambrian (Fortunian) of China with a characteristic echinoderm-like plated theca, a muscular stalk reminiscent of the hemichordates and a pair of feeding appendages. Our phylogenetic analysis indicates that Y. biscarpa is a stem-echinoderm and not only is this species the oldest and most basal echinoderm, but it also predates all known hemichordates, and is among the earliest deuterostomes. This taxon confirms that echinoderms acquired plating before pentaradial symmetry and that their history is rooted in bilateral forms. Yanjiahella biscarpa shares morphological similarities with both enteropneusts and echinoderms, indicating that the enteropneust body plan is ancestral within hemichordates.

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  • 2097.
    Topper, Timothy P.
    et al.
    Uppsala Universitet.
    Holmer, Lars E.
    Uppsala Universitet.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Balthasar, Uwe
    University of Glasgow.
    Harper, David A.T.
    The oldest brachiopods from the lower Cambrian of South Australia2013In: Acta Palaeontologica Polonica, ISSN 0567-7920, E-ISSN 1732-2421, Vol. 58, no 1, p. 93-109Article in journal (Refereed)
    Abstract [en]

    The morphology and organophosphatic shell structure of the paterinate brachiopod Askepasma is documented using new and previously collected specimens from the lower Cambrian of South Australia. Lack of adequately preserved material has seen the majority of paterinate specimens previously reported from South Australia referred to the genus Askepasma and treated under open nomenclature. Large collections of paterinates from the lower Cambrian Wilkawillina, Ajax, and Wirrapowie limestones in the Arrowie Basin, South Australia have prompted redescription of the type species Askepasma toddense and the erection of a new species, Askepasma saproconcha sp. nov. Askepasma saproconcha sp. nov. currently represents the oldest known brachiopod from the lower Cambrian successions in South Australia with a FAD in pre−trilobitic (Terreneuvian, Cambrian Stage 2, lower Atdabanian) strata in the basal part of the Wilkawillina and Wirrapowie limestones. Askepasma toddense predominantly occurs in Abadiella huoi Zone equivalent strata (Unnamed Cambrian Series 2, Stage 3, middle–upper Atdabanian) in the upper part of the lower Wilkawillina, Wirrapowie, and Ajax limestones. The shell microstructure of Askepasma suggests a proximal stem group position within the Brachiopoda and similarities with tommotiid taxa provides further evidence that the ancestry of crown group brachiopods is firmly entrenched within the Tommotiida.

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  • 2098.
    Topper, Timothy P.
    et al.
    Geological Museum, Copenhagen.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Ahlberg, Per
    Lunds Universitet.
    A Bradoriid and Brachiopod Dominated Shelly Fauna from the Furongian (Cambrian) of Västergötland, Sweden2013In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 87, no 1, p. 69-83Article in journal (Refereed)
    Abstract [en]

    A small assemblage of shelly fossils, dominated by the brachiopod Treptotreta jucunda and the bradoriid arthropod Mongolitubulus aspermachaera new species is described from a Furongian limestone of Västergötland, south-central Sweden. Mongolitubulus aspermachaera is represented in the assemblage by individual valves and numerous, ornamented spines. Valves and spines share identical ornament and microstructure leaving no doubt that the isolated spines were once attached to the bradoriid valves. Mongolitubulus aspermachaera adds to the increasing list of spinose Cambrian bradoriid arthropods, and Mongolitubulidae new family is erected here to incorporate the genera Mongolitubulus, Tubuterium and Spinospitella. Mongolitubulus aspermachaera represents the youngest member of the new family and supplements the biodiversity of bradoriids in the Furongian, an interval when bradoriid diversity is considered to be very much on the decline. The brachiopod Treptotreta jucunda described predominantly from the ‘middle' to ‘late' Cambrian of Australia is here documented for the first time from outside Gondwana, dramatically extending the biogeographical range of the species. Other elements of the faunal assemblage include typical Baltic Furongian representatives, such as the trilobite Parabolina, the agnostoid Agnostus and the phosphatocopids Hesslandona and Vestrogothia.

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  • 2099.
    Topper, Timothy P.
    et al.
    Geologisk Museum, Statens Naturhistoriske Museum, Danmark.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    A new name for a classic Cambrian Swedish brachiopod, Tallatella undosa (Moberg)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 3, p. 429-435Article in journal (Refereed)
    Abstract [en]

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

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    Topper and Skovsted 2014 - Tallatella manuscript
  • 2100. Topper, Timothy, P.
    et al.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Keeping a lid on it: muscle scars and the mystery of the Mobergellidae2017In: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 180, p. 717-731Article in journal (Refereed)
    Abstract [en]

    Mobergellans were one of the first Cambrian skeletal groups to be recognized yet have long remained one of the mostproblematic in terms of biological function and affinity. Characterized by a disc-shaped, phosphatic sclerite, the mostdistinctive character of the group is a prominent set of internal scars, interpreted as representing sites of former muscleattachment. Predominantly based on muscle scar distribution, mobergellans have been compared to brachiopods,bivalves and monoplacophorans; however, a recurring theory that the sclerites acted as an operculum remains untested.Rather than correlate the number of muscle scars between taxa, here we focus on the percentage of the inner surfaceshell area that the scars constitute. We investigate two mobergellan species, Mobergella holsti and Discinella micans,and compare the Cambrian taxa with the muscle scars of a variety of extant and fossil marine invertebrate taxa to testwhether the mobergellan muscle attachment area is compatible with an interpretation as operculum. The only skeletalelements in our study with a comparable muscle attachment percentage are gastropod opercula. Complemented withadditional morphological information, our analysis supports the theory that mobergellan sclerites acted as an operculumpresumably from a tube-living organism. The paucity of tubes co-occurring with mobergellan sclerites could beexplained by the transportation and sorting of detached opercula, while the corresponding tube remained attached tosubstrata in shallower water. The operculum perhaps performed a similar role to that seen in serpulid annelids and inneritid gastropods sealing the living chamber of the organism to avoid desiccation or for protection.

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