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A quantitative comparison of dispersed spore/pollen and plant megafossil assemblages from a Middle Jurassic plant bed from Yorkshire, UK
- Sam M. Slater, Charles H. Wellman
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- Journal:
- Paleobiology / Volume 41 / Issue 4 / September 2015
- Published online by Cambridge University Press:
- 14 October 2015, pp. 640-660
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Detailed quantitative data has previously been collected from plant megafossil assemblages from a Middle Jurassic (Aalenian) plant bed from Hasty Bank, North Yorkshire, UK. We conducted a similar analysis of palynological dispersed sporomorph (spore and pollen) assemblages collected from the same section using the same sampling regime: 67 sporomorph taxa were recorded from 50 samples taken at 10 cm intervals through the plant bed. Basic palynofacies analysis was also undertaken on each sample. Both dispersed sporomorph and plant megafossil assemblages display consistent changes in composition, diversity (richness), and abundance through time. However, the dispersed sporomorph and plant megafossil records provide conflicting evidence for the nature of parent vegetation. Specifically, conifers and ferns are underrepresented in plant megafossil assemblages, bryophytes and lycopsids are represented only in sporomorph assemblages, and sphenophytes, pteridosperms, Caytoniales, Cycadales, Ginkgoales and Bennettitales are comparatively underrepresented in sporomorph assemblages. Combined multivariate analysis (correspondence analysis and nonmetric multidimensional scaling) of sporomorph occurrence/abundance data demonstrates that temporal variation in sporomorph assemblages is the result of depositional change through the plant bed. The reproductive strategies of parent plants are considered to be a principal factor in shaping many of the major abundance and diversity irregularities between dispersed sporomorph and plant megafossil data sets that seemingly reflects different parent vegetation. Preferential occurrence/preservation of sporomorphs and equivalent parent plants is a consequence of a complex array of biological, ecological, geographical, taphonomic, and depositional factors that act inconsistently between and within fossil assemblages, which results in notable discrepancies between data sets.
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- The Cambridge Dictionary of Philosophy
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- 05 August 2015
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- 27 April 2015, pp ix-xxx
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Spore assemblages from the Lower Devonian ‘Lower Old Red Sandstone’ deposits of the Northern Highlands of Scotland: the Berriedale Outlier
- Charles H. Wellman
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- Journal:
- Earth and Environmental Science Transactions of The Royal Society of Edinburgh / Volume 105 / Issue 3 / September 2014
- Published online by Cambridge University Press:
- 01 June 2015, pp. 227-238
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- September 2014
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Assemblages of well-preserved dispersed spores have been recovered from the ‘Lower Old Red Sandstone’ deposits of the Berriedale Outlier in the Northern Highlands of Scotland. They belong to the annulatus–sextantii Spore Assemblage Biozone (AS SAB), in the spore zonation of Richardson & McGregor (1986), indicating an Early Devonian Emsian (but not earliest Emsian or latest Emsian) age. Comparison with the spore zonation of Streel et al. (1987) suggests they may be confined to the annulatus–bellatulus Oppel Zone (AB OZ), further constraining the age to early Emsian. This new biostratigraphical datum provides an age constraint for the onset of ‘Lower Old Red Sandstone’ sedimentation in the Orcadian Basin and, in particular, northwest of the Great Glen Fault System on the Northern Highlands. In the Orcadian Basin, there is a gap between ‘Lower Old Red Sandstone’ and ‘Middle Old Red Sandstone’ sedimentation, represented by either unconformity or disconformity, which appears to be variable in duration. In the Berriedale Outlier, it is estimated to represent up to 16 million years, but with an unknown thickness of ‘Lower Old Red Sandstone’ sequence removed at the unconformity. However, this basin-wide unconformity/disconformity is likely due to minor, local rather than large-scale, regional tectonism, and the evidence suggests little, if any, syn-depositional strike-slip movement along the Great Glen Fault System during Devonian ‘Old Red Sandstone’ deposition. The described spore assemblage is the most diverse AS SAB/AB OZ assemblage described from the British Isles. However, compared to contemporary spore assemblages from elsewhere on the Old Red Sandstone continent, the Scottish material is rather depauperate, with certain key taxa absent. This probably reflects subtle ecological effects, with the Scottish material representing restricted floras of the inland intermontaine basins.
Spore assemblages from the Lower Devonian ‘Lower Old Red Sandstone’ deposits of Arran, Scotland
- Charles H. Wellman
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- Journal:
- Earth and Environmental Science Transactions of The Royal Society of Edinburgh / Volume 100 / Issue 4 / December 2009
- Published online by Cambridge University Press:
- 01 December 2009, pp. 391-397
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- December 2009
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Dispersed spore assemblages have been recovered from the Am Binnein Sandstones from the upper part of the ‘Lower Old Red Sandstone’ sequence on the island of Arran, Scotland. The spore assemblages belong with the Emphanisporites annulatus–Camarozonotriletes sextantii (AS) Spore Assemblage Biozone (SAB), indicating an Early Devonian, Emsian (but not earliest Emsian or latest Emsian) age. This is the first reliable age constraint for the ‘Lower Old Red Sandstone’ of Arran, and enables correlation with the more extensive sequence developed on the mainland in the Midland Valley of Scotland. The Am Binnein Sandstones are confirmed as correlatives of the Strathmore Group.
Palynology of the ‘Lower Old Red Sandstone’ at Glen Coe, Scotland
- Charles H. Wellman
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- Geological Magazine / Volume 131 / Issue 4 / July 1994
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- 01 May 2009, pp. 563-566
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‘Lower Old Red Sandstone’ deposits preserved by cauldron subsidence at Glen Coe, Scotland have hitherto lacked secure biostratigraphical age constraint. A sporomorph assemblage recovered from basal sediments of these deposits permits age determination, despite being highly carbonized. The sporomorph assemblage is correlated with the micrornatus-newportensis Sporomorph Assemblage Biozone, indicating a late early-early late Lochkovian age (early Devonian). Sporomorph assemblages from basal sediments of the ‘Lower Old Red Sandstone’ sequence at nearby Lorne, a suggested correlative of the Glen Coe deposits, are older (latest Pridoli-earliest Lochkovian age). However, the new biostratigraphical data do not preclude the possibility that the Glen Coe and Lorne deposits are lithological correlatives and the basal sediments are diachronous.
Spore assemblages from the Lower Devonian ‘Lower Old Red Sandstone’ deposits of the Rhynie outlier, Scotland
- Charles H. Wellman
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- Journal:
- Transactions of the Royal Society of Edinburgh: Earth Sciences / Volume 97 / Issue 2 / June 2006
- Published online by Cambridge University Press:
- 26 July 2007, pp. 167-211
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- June 2006
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Since the late 1980s an extensive programme of trenching/borehole drilling has been undertaken in order to study the Lower Devonian ‘Lower Old Red Sandstone’ deposits of the Rhynie outlier in the Grampian Highlands of Scotland. The boreholes have provided new information on the stratigraphical succession and geological structure of the Rhynie outlier, both of which were hitherto poorly understood due to the paucity of good surface exposure and the complex geological relationships of the deposits. One hundred and eighteen palynological samples were collected, representing much of the stratigraphical sequence of the inlier, of which 106 were productive. Productive samples yield assemblages of well preserved palynomorphs, dominated by spores and phytodebris, but also containing arthropod cuticle and rare freshwater algal remains. The spore assemblages are systematically described and two new genera and six new species proposed. They are similar throughout the sequence and the spores belong to the polygonalis–emsiensis Spore Assemblage Biozone of Richardson & McGregor (1986) and the PoW Oppel Zone (possibly Su Interval Zone) of Streel et al. (1987), indicating an early (but not earliest) Pragian–?earliest Emsian age range, that may possibly be restricted to latest Pragian–?earliest Emsian. The palynomorph assemblages contain only terrestrial forms, supporting sedimentological interpretation of the deposits as ‘Lower Old Red Sandstone’ fluviatile and lacustrine deposits, with occasional extrusive volcanics and volcaniclastic sediments intercalated. The palynomorphs are of variable thermal maturity (within and between samples), probably reflecting differential heating associated with the complex volcanic/hydrothermal system. The new palynological data provide, for the first time, a reliable biostratigraphical age for the deposits, and suggest that they accumulated relatively rapidly. Spore biostratigraphy and thermal maturity studies facilitate correlation of the tectonically complex deposits, and shed light on other aspects of the geological history of the outlier. The palynomorph assemblages also aid interpretation of the biota of the Rhynie basin, including the exceptionally preserved biotas of the Rhynie and Windyfield cherts.
Spores of the Rhynie chert plant Horneophyton lignieri (Kidston & Lang) Barghoorn & Darrah, 1938
- Charles H. Wellman, Hans Kerp, Hagen Hass
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- Journal:
- Transactions of the Royal Society of Edinburgh: Earth Sciences / Volume 94 / Issue 4 / December 2003
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- 26 July 2007, pp. 429-443
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- December 2003
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Detailed studies have been undertaken on in situ spores of the plant Horneophyton lignieri (Kidston & Lang) Barghoorn & Darrah, 1938 preserved in the Rhynie chert. It is concluded that mature spores are trilete, with proximal radial ribbing, and a distal ornament of coni. These spores are identical to Emphanisporites decoratus Allen, 1965, a widely reported and morphologically distinctive dispersed spore taxon. Emphanisporites decoratus is a common element of dispersed spore assemblages from throughout the stratigraphical sequence of the Rhynie outlier, and it is concluded that the dispersed spore taxon E. decoratus was produced by H. lignieri. The nature (reproductive biology, ecology and distribution) of H. lignieri is interpreted on the basis of evidence from the dispersed spore record from the Rhynie outlier and elsewhere. It is concluded that H. lignieri was a common and widespread plant of the Lower Devonian. It flourished in the unusual hot springs environment of the Rhynie chert because it was preadapted to do so, not because it was a highly specialized and adapted plant. Integrated evidence from the in situ and dispersed spore records permits a detailed consideration of the biology of the plant H. lignieri.
A Lower Devonian sporomorph assemblage from the Midland Valley of Scotland
- Charles H. Wellman
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- Journal:
- Transactions of the Royal Society of Edinburgh: Earth Sciences / Volume 84 / Issue 2 / 1993
- Published online by Cambridge University Press:
- 03 November 2011, pp. 117-136
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- 1993
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A sporomorph assemblage recovered from the Sandy's Creek Beds, which constitute a diminutive fault bounded inlier on the west coast of the Midland Valley of Scotland, is described. Four species of trilete spore and the genus Fustisispora, a monospecific cryptospore genus, are proposed as new. The sporomorph assemblage is attributed an early Devonian, late–early to early–late Lochkovian age, and is interpreted as accumulating in a continental environment. The Sandy's Creek Beds are correlated herein with the upper part of the Arbuthnott Group which crops out in the north-east of the Midland Valley. Comparison with other sporomorph assemblages of similar age indicates that minor regional variation exists. It is suggested that this is related to small-scale regional variation in the composition of vegetation.