DOCSLIB.ORG

Early Cretaceous Macrofloras of Western Australia

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Early Cretaceous Macrofloras of Western Australia Records of the Westem Australian Museum 18: 19-65 (1996), Early Cretaceous macrofloras of Western Australia Stephen McLoughlin School of Botany, The University of Melbourne, Parkville, Victoria 3052, Australia Abstract - Western Australian, Lower Cretaceous, macrofloras from the Broome Sandstone and Callawa Formation (Canning Basin), Nanutarra Formation and Birdrong Sandstone (Carnarvon Basin), Cronin Sandstone (Officer Basin), and Leederville and Bullsbrook Formations (Perth Basin) incorporate a range of lycophytes, ferns, pteridosperms, bennettitaleans, and conifers, The new monotypic genus Roebuckia is established for spatulate fern fronds (R, spatulata) of possible vittariacean alliance. Other newly established species include Phyllopteroides westralensis, Elatocladus ginginensis, and Carpolithes bullsbrookensis, Although the Western Australian fossil suites reveal some specific differences from other Australian late Mesozoic assemblages, several shared index taxa and the high proportion of bennettitaleans support correlation with the Victorian Neocomian Ptilophyllum-Pachypteris austropapillosa Zone (Zone B). Some Western Australian taxa are shared with Indian assemblages but fewer similarities exist with other Gondwanan Early Cretaceous floras, The representation of several hydrophilous fern, lycophyte, and pteridosperm groups together with growth indices from fossil woods implies a seasonal humid mesothermal climate for the Western Australian eratonic margin during the Neocomian-Barremian. Minor differences between the Western Australian assemblages are attributable to local depositional and preservational factors. INTRODUCTION assemblages of plant macrofossils from subsurface This paper reviews all Western Australian Cretaceous strata in Western Australia. Retallack Cretaceous plant fossils held in the collections of (1977, 1980) and McLoughlin (1993) have the Western Australian Museum and the illustrated differences in palaeosol development Department of Geology and Geophysics of the and the composition of plant fossil assemblages in University of Western Australia together with Australian Permian and Triassic strata according limited material held in the Australian Museum, to variations in local and regional depositional Sydney, As all specimens lack preserved organic settings. Such sedimentological and taphonomic matter, descriptions are based on gross controls also apply to the Cretaceous assemblages morphology, ornamentation, and venation offering an important tool for detailed patterns. This procedure necessarily places interpretation of non-marine sedimentary facies. limitations on the degree of discrimination between Additionally, permineralized, mollusc-bored, some taxa. However, the scarcity of previous driftwood preserved in Lower Cretaceous marine studies on the Western Australian fossil floras sediments has aided the definition of sequence invites this systematic appraisal in order to fill stratigraphic boundaries and systems tracts some major gaps in the knowledge of Australia's (McLoughlin et al. 1994). Palaeobotanical Cretaceous phytogeography. investigations of the diversity of plant groups The relative tectonic stability and deep­ together with anatomical indices such as growth weathering associated with much of the central ring variation are also useful for the categorization and western part of the Australian continent since of palaeoclimates and the identification of major the mid-Mesozoic has removed from outcrops food sources available to the large Cretaceous most of the organic material required for herbivorous dinosaurs. palynological studies. Apart from scarce vertebrate trackways (Colbert and Merrilees 1967; Long 1990), plant macrofossils are virtually the only fossil PREVIOUS STUDIES remains available in outcrop to date and Douglas (1969, 1973), Drinnan and Chambers palaeoenvironmentally categorize Western (1986) and McLoughlin et al. (1995) have provided Australian Cretaceous terrestrial strata. No studies the most detailed studies of Australian Cretaceous dealing with stratigraphic and petroleum fossil plants dealing with macrofloras from the exploration drilling have reported significant Gippsland, Otway and Eromanga Basins. Other 20 s. McLoughlin 113°E o 600 KILOMETRES Figure 1 Map of Western Australia showing Phanerozoic sedimentary basins and principal Cretaceous plant macrofossil localities (solid squares). significant contributions include those of Seward McLoughlin et al. (1994) detailed the anatomical (1904), Chapman (1908, 1909, 1914), Walkom (1918, character and palaeoenvironmental significance of 1919a), Medwell (1954a,b), Glaessner and Rao silicified and phosphatized woods from the (1955), and Dettmann et al. (1992). Although Birdrong Sandstone, Carnarvon Basin and several stratigraphic papers have provided lists of Backhouse et al. (1995) described lignitized but fossil plants recovered from Western Australian anatomically similar woods from the Barremian to Cretaceous strata (e.g., Brunnschweiler 1960; Cox earliest Aptian Nakina Formation of the Collie 1961; Playford et aI. 1976) many of these Basin. The Cretaceous palaeobotanical literature identifications are not supported by illustrations or from other Gondwanan continents (especially India descriptions and are commonly erroneous. A small and South America) is extensive. Therefore, assemblage described and illustrated by Walkom synonymy lists provided here deal only with (1944) from strata underlying the Molecap previously figured or described Western Greensand near Gingin is redescribed herein. Australian fossil plants. White (1961a) briefly described and illustrated plant remains recovered from the Canning Basin by Australian Bureau of Mineral Resources CRETACEOUS STRATIGRAPHY regional geological surveys. McLoughlin and Western Australian Cretaceous plant Guppy (1993), and McLoughlin and Hill (in press) macrofossils have been recovered from the Perth, provided preliminary revised lists of Western Carnarvon, Canning, and Officer Basins (Figure 1). Australian Cretaceous plant fossils from several Plant remains are best represented in Early sedimentary basins and briefly discussed some Cretaceous non-marine strata (Figure 2). Due to a palaeoclimatic implications of the floras. dearth of palynological studies and the absence of -------------------------------------------------- Early Cretaceous macrofloras 21 marine invertebrate biostratigraphic indices, the However, Feldtman (1963) reported that the plant­ ages of many of these rock units are only broadly bearing horizons occurred within the Strathalbyn constrained. Furthermore, lack of continuous Beds, a term which Playford et al. (1976) regarded outcrops in many areas hinders the mapping and as synonymous with the Leederville Formation. lithological correlation of plant-bearing strata and Wilde and Low (1978) also mapped outcrops in the has led to uncertainties over the application of vicinity of Walkom's plant beds (Cheriton Creek) lithostratigraphic names. For example, Playford et as part of the Leederville Formation. On the basis al. (1976) and Skwarko (1990) assigned Walkom's of lithology and stratigraphic position, the fossils (1944) Gingin fossil assemblage to the Yarragadee are here regarded as belonging to the marine to Formation (Middle Jurassic to Tithonian). continental Leederville Formation (Hauterivian- LOWER PERTH BASIN CARNARVON CANNING BASIN CRETACEOUS (Dandara~an BASIN (Anketell Shelf & STAGES Trough kGascoyne Broome Platform); ub-basin) OFFICER BASIN Osborne ALBIAN Formation Windalia Radiolarite 0 n ete s rezie 0 / ~ .-l «.-l (9 APTIAN iJ u Muderong Dandaragan Sh Sandstone Cl. ::J 0 0 0 .... Birdrong Sst .!.!!c .:::&.c <.!J =0 00 BARREMIAN c: '';= 0·- 0 m eel ..a«l .... "OEm .... -ClJE.... .0 mo "So c ...JLL COLL .... 0 eel m 0 ~ r-- HAUTERIVIAN s: m 0 E Z 0 c m South 0> 0 c m -.~ -0 -c « - c c -Perth 0 0 0 1i5 ~ Shale () .~ "0 1i5 E C "0 VALANGINIAN eel - 0 eel C 0 E LL (j) eel 0 <5 .... (j) 0 0 eel m 0 ~ LL ~ E c W .... ....eel eel 0 C Z ~ .... Cii ....0 0.... eel () CO () BERRIASIAN S Parmelia c Formation zeel Fossil leaves _ Permineralized wood 0 Figure 2 Stratigraphic correlation of Lower Cretaceous rock units in the Perth, Carnarvon, and Canning Basins, Western Australia (after Cockbain 1990; Hocking 1990; Middleton 1990) showing the distribution of plant macrofossi! assemblages. 22 s. McLoughlin Barremian): Figure 2. The Bullsbrook Formation, preserved in ferruginous shale and medium­ exposed 2 km east of Bullsbrook, is a fully grained quartzose sandstone apart from some continental lateral equivalent of the Leederville seeds, megaspores, and axes which are preserved Formation (Figure 2). as natural day or sandstone casts. Organic material The Neocomian-?Aptian shallow marine to was not preserved on any fossils but in some cases paralic Birdrong Sandstone is chiefly exposed latex and silicone casts yielded morphological along the Murchison River near Kalbarri, on the details not clearly evident on negative impressions. flanks of the Kennedy Ranges, and in the Giralia All specimens were illustrated under strong Anticline within the Carnarvon Basin (Hocking et unilateral light directed from the upper left unless al. 1987; McLoughlin et al. 1994). The upper part of otherwise stated. this unit is typically rich in fragmentary Fossil localities are as follows: permineralized gymnosperm wood showing Broome Sandstone - Gantheaume Point, Broome evidence of intensive molluscan borings. Other (material collected by W.H Butler, A. Dawson, Cretaceous
Load more

Recommended publications
  • Gymnosperm Foliage from the Upper Triassic of Lunz, Lower Austria: an Annotated Check List and Identification Key
    Geo.Alp, Vol. 7, S. 19–38, 2010 GYMNOSPERM FOLIAGE FROM THE UPPER TRIASSIC OF LUNZ, LOWER AUSTRIA: AN ANNOTATED CHECK LIST AND IDENTIFICATION KEY Christian Pott1 & Michael Krings2 With 7 figures and 1 table 1 Naturhistoriska riksmuseet, Sektionen för paleobotanik, Box 50007, SE-104 05 Stockholm, Sweden; [email protected] 2 Department für Geo- und Umweltwissenschaften, Paläontologie und Geobiologie, Ludwig-Maximilians-Universität, and Bayerische Staatssammlung für Paläontologie und Geologie, Richard-Wagner-Straße 10, 80333 München, Germany; [email protected] Abstract The famous Lunz flora from Lower Austria is one of the richest and most diverse Late Triassic floras of the Northern He- misphere. The historical outcrops (mainly coal mines) are no longer accessible, but showy fossils can still be collected from natural exposures around the town of Lunz-am-See and from several of the old spoil tips. This paper presents an annotated check list with characterisations of all currently recognised gymnosperm foliage taxa in the Lunz flora. The descriptions are exemplified by illustrations of typical specimens and diagnostic features of the leaf morphology and epidermal anatomy. Moreover, a simple identification key for the taxa based on macromorphological features is provided that facilitates identification of newly collected specimens. 1. Introduction The Carnian (Late Triassic) flora from Lunz in Lo- ments (i.e. reproductive structures) among the fossils wer Austria is one of only a few well-preserved flo- (see e.g., Krasser, 1917, 1919; Kräusel, 1948, 1949, ras from the Alpine Triassic (Cleal, 1993; Dobruskina, 1953; Pott et al., 2010), the most striking feature of 1998).
    [Show full text]
  • Middle Jurassic Plant Diversity and Climate in the Ordos Basin, China Yun-Feng Lia, B, *, Hongshan Wangc, David L
    ISSN 0031-0301, Paleontological Journal, 2019, Vol. 53, No. 11, pp. 1216–1235. © Pleiades Publishing, Ltd., 2019. Middle Jurassic Plant Diversity and Climate in the Ordos Basin, China Yun-Feng Lia, b, *, Hongshan Wangc, David L. Dilchera, b, d, E. Bugdaevae, Xiao Tana, b, d, Tao Lia, b, Yu-Ling Naa, b, and Chun-Lin Suna, b, ** aKey Laboratory for Evolution of Past Life and Environment in Northeast Asia, Jilin University, Changchun, Jilin, 130026 China bResearch Center of Palaeontology and Stratigraphy, Jilin University, Changchun, Jilin, 130026 China cFlorida Museum of Natural History, University of Florida, Gainesville, Florida, 32611 USA dDepartment of Earth and Atmospheric Sciences, Indiana University, Bloomington, Indiana, 47405 USA eFederal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch of Russian Academy of Sciences, Vladivostok, 690022 Russia *e-mail: [email protected] **e-mail: [email protected] Received April 3, 2018; revised November 29, 2018; accepted December 28, 2018 Abstract—The Ordos Basin is one of the largest continental sedimentary basins and it represents one major and famous production area of coal, oil and gas resources in China. The Jurassic non-marine deposits are well developed and cropped out in the basin. The Middle Jurassic Yan’an Formation is rich in coal and con- tains diverse plant remains. We recognize 40 species in 25 genera belonging to mosses, horsetails, ferns, cycadophytes, ginkgoaleans, czekanowskialeans and conifers. This flora is attributed to the early Middle Jurassic Epoch, possibly the Aalenian-Bajocian. The climate of the Ordos Basin during the Middle Jurassic was warm and humid with seasonal temperature and precipitation fluctuations.
    [Show full text]
  • Prepared in Cooperation with the Lllinois State Museum, Springfield
    Prepared in cooperation with the lllinois State Museum, Springfield Richard 1. Leary' and Hermann W. Pfefferkorn2 ABSTRACT The Spencer Farm Flora is a compression-impression flora of early Pennsylvanian age (Namurian B, or possibly Namurian C) from Brown County, west-central Illinois. The plant fossils occur in argillaceous siltstones and sand- stones of the Caseyville Formation that were deposited in a ravine eroded in Mississippian carbonate rocks. The plant-bearing beds are the oldest deposits of Pennsylva- nian age yet discovered in Illinois. They were formed be- fore extensive Pennsylvanian coal swamps developed. The flora consists of 29 species and a few prob- lematical forms. It represents an unusual biofacies, in which the generally rare genera Megalopteris, Lesleya, Palaeopteridium, and Lacoea are quite common. Noegger- athiales, which are seldom present in roof-shale floras, make up over 20 percent of the specimens. The Spencer Farm Flora is an extrabasinal (= "upland1') flora that was grow- ing on the calcareous soils in the vicinity of the ravine in which they were deposited. It is suggested here that the Noeggerathiales may belong to the Progymnosperms and that Noeggerathialian cones might be derived from Archaeopteris-like fructifica- tions. The cone genus Lacoea is intermediate between Noeggerathiostrobus and Discini tes in its morphology. Two new species, Lesleya cheimarosa and Rhodeop- teridi urn phillipsii , are described, and Gulpenia limbur- gensis is reported from North America for the first time. INTRODUCTION The Spencer Farm Flora (table 1) differs from other Pennsylvanian floras of the Illinois Basin. Many genera and species in the Spencer Farm Flora either have not been found elsewhere in the basin or are very l~uratorof Geology, Illinois State Museum, Springfield.
    [Show full text]
  • Re-Evaluation of the Genus Rubidgea in the Lower Permian of the Paraná Basin, Brazil, and Its Biostratigraphic Consequence
    Versão online: http://www.lneg.pt/iedt/unidades/16/paginas/26/30/185 Comunicações Geológicas (2014) 101, Especial I, 455-457 IX CNG/2º CoGePLiP, Porto 2014 ISSN: 0873-948X; e-ISSN: 1647-581X Re-evaluation of the genus Rubidgea in the Lower Permian of the Paraná Basin, Brazil, and its biostratigraphic consequence Reavaliação do género Rubidgea, no Pérmico Inferior da Bacia do Paraná, Brasil, e suas consequências bioestratigráficas R. Iannuzzi1*, G. P. Tybusch1 Artigo Curto Short Article © 2014 LNEG – Laboratório Nacional de Geologia e Energia IP Abstract: The plant megafossil specimens revised in this study came *Corresponding author / Autor correspondente: [email protected] from the outcrops located in the São Paulo and Rio Grande do Sul states and positioned stratigraphically on top of the Itararé Group 1. Introduction and/or base of the Rio Bonito (= Tietê) Formation, Lower Permian of the Paraná Basin. The study material comprises leaves fragments The record of the genus Rubidgea in Brazil was first preserved as impressions, previously included in the morphogenus mentioned by Cazzulo-Klepzig et al. (1980) for the Itararé Rubidgea because of their supposed gangamopterid venation pattern, Group of the Rio Grande do Sul state, and it is represented lacking anastomoses. However, re-evaluation of this material showed by a specimen classified as Rubidgea sp. Later, Rubidgea that these leaves bear at some degree, rare anastomoses along the lamina. Based on this observation, we proposed that these leaves obovata Maithy (1965) and Rubidgea lanceolatus Maithy should be transferred to the morphogenus Gangamopteris, which (1965) were illustrated and reported for the outcrops displays this type of venation.
    [Show full text]
  • Plant Mobility in the Mesozoic Disseminule Dispersal Strategies Of
    Palaeogeography, Palaeoclimatology, Palaeoecology 515 (2019) 47–69 Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Plant mobility in the Mesozoic: Disseminule dispersal strategies of Chinese and Australian Middle Jurassic to Early Cretaceous plants T ⁎ Stephen McLoughlina, , Christian Potta,b a Palaeobiology Department, Swedish Museum of Natural History, Box 50007, 104 05 Stockholm, Sweden b LWL - Museum für Naturkunde, Westfälisches Landesmuseum mit Planetarium, Sentruper Straße 285, D-48161 Münster, Germany ARTICLE INFO ABSTRACT Keywords: Four upper Middle Jurassic to Lower Cretaceous lacustrine Lagerstätten in China and Australia (the Daohugou, Seed dispersal Talbragar, Jehol, and Koonwarra biotas) offer glimpses into the representation of plant disseminule strategies Zoochory during that phase of Earth history in which flowering plants, birds, mammals, and modern insect faunas began to Anemochory diversify. No seed or foliage species is shared between the Northern and Southern Hemisphere fossil sites and Hydrochory only a few species are shared between the Jurassic and Cretaceous assemblages in the respective regions. Free- Angiosperms sporing plants, including a broad range of bryophytes, are major components of the studied assemblages and Conifers attest to similar moist growth habitats adjacent to all four preservational sites. Both simple unadorned seeds and winged seeds constitute significant proportions of the disseminule diversity in each assemblage. Anemochory, evidenced by the development of seed wings or a pappus, remained a key seed dispersal strategy through the studied interval. Despite the rise of feathered birds and fur-covered mammals, evidence for epizoochory is minimal in the studied assemblages. Those Early Cretaceous seeds or detached reproductive structures bearing spines were probably adapted for anchoring to aquatic debris or to soft lacustrine substrates.
    [Show full text]
  • A Palaeoenvironmental Reconstruction of the Middle Jurassic of Sardinia (Italy) Based on Integrated Palaeobotanical, Palynological and Lithofacies Data Assessment
    Palaeobio Palaeoenv DOI 10.1007/s12549-017-0306-z ORIGINAL PAPER A palaeoenvironmental reconstruction of the Middle Jurassic of Sardinia (Italy) based on integrated palaeobotanical, palynological and lithofacies data assessment Luca Giacomo Costamagna1 & Evelyn Kustatscher2,3 & Giovanni Giuseppe Scanu1 & Myriam Del Rio1 & Paola Pittau1 & Johanna H. A. van Konijnenburg-van Cittert4,5 Received: 15 May 2017 /Accepted: 19 September 2017 # The Author(s) 2017. This article is an open access publication Abstract During the Jurassic, Sardinia was close to con- diverse landscape with a variety of habitats. Collection- tinental Europe. Emerged lands started from a single is- and literature-based palaeobotanical, palynological and land forming in time a progressively sinking archipelago. lithofacies studies were carried out on the Genna Selole This complex palaeogeographic situation gave origin to a Formation for palaeoenvironmental interpretations. They evidence a generally warm and humid climate, affected occasionally by drier periods. Several distinct ecosystems can be discerned in this climate, including alluvial fans This article is a contribution to the special issue BJurassic biodiversity and with braided streams (Laconi-Gadoni lithofacies), paralic ^ terrestrial environments . swamps and coasts (Nurri-Escalaplano lithofacies), and lagoons and shallow marine environments (Ussassai- * Evelyn Kustatscher [email protected] Perdasdefogu lithofacies). The non-marine environments were covered by extensive lowland and a reduced coastal Luca Giacomo Costamagna and tidally influenced environment. Both the river and the [email protected] upland/hinterland environments are of limited impact for Giovanni Giuseppe Scanu the reconstruction. The difference between the composi- [email protected] tion of the palynological and palaeobotanical associations evidence the discrepancies obtained using only one of those Myriam Del Rio [email protected] proxies.
    [Show full text]
  • The Lower Cretaceous Flora of the Gates Formation from Western Canada
    The Lower Cretaceous Flora of the Gates Formation from Western Canada A Shesis Submitted to the College of Graduate Studies and Research in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in the Department of Geological Sciences Univ. of Saska., Saskatoon?SI(, Canada S7N 3E2 b~ Zhihui Wan @ Copyright Zhihui Mian, 1996. Al1 rights reserved. National Library Bibliothèque nationale 1*1 of Canada du Canada Acquisitions and Acquisitions et Bibliographic Services services bibliographiques 395 Wellington Street 395. rue Wellington Ottawa ON KlA ON4 Ottawa ON K1A ON4 Canada Canada The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exclusive permettant à la National Libraxy of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microfom, vendre des copies de cette thèse sous paper or electronic formats. la fome de microfiche/nlm, de reproduction sur papier ou sur foxmat électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fiom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. College of Graduate Studies and Research SUMMARY OF DISSERTATION Submitted in partial fulfillment of the requirernents for the DEGREE OF DOCTOR OF PHILOSOPHY ZHIRUI WAN Depart ment of Geological Sciences University of Saskatchewan Examining Commit tee: Dr.
    [Show full text]
  • Sementes Do Gênero Samaropsis Goeppert No Permiano Inferior Da Bacia Do Paraná, Sul Do Brasil
    Rev. bras. paleontol. 10(2):95-106, Maio/Agosto 2007 © 2007 by the Sociedade Brasileira de Paleontologia SEMENTES DO GÊNERO SAMAROPSIS GOEPPERT NO PERMIANO INFERIOR DA BACIA DO PARANÁ, SUL DO BRASIL JULIANE MARQUES DE SOUZA & ROBERTO IANNUZZI Departamento de Paleontologia e Estratigrafia, Instituto de Geociências, UFRGS, Cx. P. 15001, 91501-970, Porto Alegre, RS, Brasil. [email protected], [email protected] RESUMO – O afloramento Morro do Papaléo, localizado no município de Mariana Pimentel, Rio Grande do Sul, tem se mostrado uma importante fonte de sementes fósseis preservadas na forma de impressões, as quais são provenientes do Grupo Itararé e da Formação Rio Bonito, Permiano Inferior da bacia do Paraná. Neste estudo são descritos seis diferentes morfotipos para o gênero Samaropsis Goeppert que, possivelmente, correspondem a seis diferentes morfoespécies. Características como a largura da sarcotesta, a forma geral da semente e do nucelo e a textura de sua superfície permitiram a proposição de uma nova espécie, Samaropsis gigas nov. sp., e identificar a presença de Samaropsis kurtzii Leguizamón, S. aff. S. millaniana Oliveira & Pontes e S. aff. S. rigbyi Millan. Além disso, uns poucos espécimes foram classificados apenas a nível genérico, tendo sido designados como Samaropsis sp. 1 e Samaropsis sp. 2. Palavras-chave: Sementes fósseis, Grupo Itararé, Formação Rio Bonito, bacia do Paraná, Rio Grande do Sul. ABSTRACT – SEEDS OF THE GENUS SAMAROPSIS GOEPPERT IN THE LOWER PERMIAN OF THE PARANÁ BASIN, SOUTHERN BRAZIL. The Morro do Papaléo outcrop is located in Mariana Pimentel town, Rio Grande do Sul, and has been an important source of fossil seeds.
    [Show full text]
  • Coevolution of Cycads and Dinosaurs George E
    Coevolution of cycads and dinosaurs George E. Mustoe* INTRODUCTION TOXICOLOGY OF EXTANT CYCADS cycads suggests that the biosynthesis of ycads were a major component of Illustrations in textbooks commonly these compounds was a trait that C forests during the Mesozoic Era, the depict herbivorous dinosaurs browsing evolved early in the history of the shade of their fronds falling upon the on cycad fronds, but biochemical evi- Cycadales. Brenner et al. (2002) sug- scaly backs of multitudes of dinosaurs dence from extant cycads suggests that gested that macrozamin possibly serves a that roamed the land. Paleontologists these reconstructions are incorrect. regulatory function during cycad have long postulated that cycad foliage Foliage of modern cycads is highly toxic growth, but a strong case can be made provided an important food source for to vertebrates because of the presence that the most important reason for the reptilian herbivores, but the extinction of two powerful neurotoxins and carcin- evolution of cycad toxins was their of dinosaurs and the contemporaneous ogens, cycasin (methylazoxymethanol- usefulness as a defense against foliage precipitous decline in cycad popula- beta-D-glucoside) and macrozamin (beta- predation at a time when dinosaurs were tions at the close of the Cretaceous N-methylamine-L-alanine). Acute symp- the dominant herbivores. The protective have generally been assumed to have toms triggered by cycad foliage inges- role of these toxins is evidenced by the resulted from different causes. Ecologic tion include vomiting, diarrhea, and seed dispersal characteristics of effects triggered by a cosmic impact are abdominal cramps, followed later by loss modern cycads. a widely-accepted explanation for dino- of coordination and paralysis of the saur extinction; cycads are presumed to limbs.
    [Show full text]
  • 6. Groundwater Resources
    6. Groundwater Resources Contents 6 Groundwater Resources 6-1 6.1 Regulatory Framework 6-1 6.1.1 Queensland Legislation 6-1 6.2 Existing Environment 6-4 6.2.1 Project Location 6-4 6.2.2 Hydrology and Landforms 6-4 6.2.3 Geology 6-4 6.2.4 Hydrogeology 6-11 6.2.5 Groundwater Use 6-16 6.2.6 Existing Mine Groundwater Monitoring 6-25 6.2.7 Revised Project Baseline Groundwater Monitoring 6-27 6.2.8 Groundwater Levels 6-31 6.2.9 Groundwater Movement 6-35 6.2.10 Inter-aquifer Connectivity 6-38 6.2.11 Surface Water and Groundwater Interaction 6-39 6.2.12 Groundwater Quality 6-39 6.2.13 Environmental Values in the EPP Water 6-47 6.2.14 Conceptual Hydrogeological Model 6-49 6.3 Impact Assessment 6-53 6.3.1 Effects on Groundwater Levels 6-55 6.3.2 Effects on Groundwater Quality 6-72 6.3.3 Effects on Groundwater Users 6-75 6.3.4 Effects on Groundwater Dependent Ecosystems 6-77 6.4 Mitigation Measures 6-77 6.4.1 Groundwater Monitoring Program 6-77 6.4.2 Landholder Bores 6-83 6.4.3 Groundwater Impact Prediction, Validation and Review 6-83 6.4.4 Mitigation Measures for affected Groundwater Users 6-84 6.5 Conclusions 6-84 New Acland Coal Mine Stage 3 Project – Environmental Impact Statement PAGE i 6 Groundwater Resources This Chapter describes the groundwater resources that may be affected by the revised Project, how they might be affected, and the measures required for the mitigation of potential negative effects.
    [Show full text]
  • Palaeogeograph Y, Palaeoclimatology, Palaeoecology , 17(1975): 157--172 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in the Netherlands
    Palaeogeograph y, Palaeoclimatology, Palaeoecology , 17(1975): 157--172 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands CLIMATIC CHANGES IN EASTERN ASIA AS INDICATED BY FOSSIL FLORAS. II. LATE CRETACEOUS AND DANIAN V. A. KRASSILOV Institute of Biology and Pedology, Far-Eastern Scientific Centre, U.S.S.R. Academy of Sciences, Vladivostok (U.S.S.R.) (Received June 17, 1974; accepted for publication November 11, 1974) ABSTRACT Krassilov, V. A., 1975. Climatic changes in Eastern Asia as indicated by fossil floras. II. Late Cretaceous and Danian. Palaeogeogr., Palaeoclimatol., Palaeoecol., 17:157--172. Four Late Cretaceous phytoclimatic zones -- subtropical, warm--temperate, temperate and boreal -- are recognized in the Northern Hemisphere. Warm--temperate vegetation terminates at North Sakhalin and Vancouver Island. Floras of various phytoclimatic zones display parallel evolution in response to climatic changes, i.e., a temperature rise up to the Campanian interrupted by minor Coniacian cooling, and subsequent deterioration of cli- mate culminating in the Late Danian. Cooling episodes were accompanied by expansions of dicotyledons with platanoid leaves, whereas the entire-margined leaf proportion increased during climatic optima. The floristic succession was also influenced by tectonic events, such as orogenic and volcanic activity which commenced in Late Cenomanian--Turonian times. Major replacements of ecological dominants occurred at the Maastrichtian/Danian and Early/Late Danian boundaries. INTRODUCTION The principal approaches to the climatic interpretation of fossil floras have been outlined in my preceding paper (Krassilov, 1973a). So far as Late Creta- ceous floras are concerned, extrapolation (i.e. inferences from tolerance ranges of allied modern taxa) is gaining in importance and the entire/non-entire leaf type ratio is no less expressive than it is in Tertiary floras.
    [Show full text]
  • Dr. Sahanaj Jamil Associate Professor of Botany M.L.S.M. College, Darbhanga
    Subject BOTANY Paper No V Paper Code BOT521 Topic Taxonomy and Diversity of Seed Plant: Gymnosperms & Angiosperms Dr. Sahanaj Jamil Associate Professor of Botany M.L.S.M. College, Darbhanga BOTANY PG SEMESTER – II, PAPER –V BOT521: Taxonomy and Diversity of seed plants UNIT- I BOTANY PG SEMESTER – II, PAPER –V BOT521: Taxonomy and Diversity of seed plants Classification of Gymnosperms. # Robert Brown (1827) for the first time recognized Gymnosperm as a group distinct from angiosperm due to the presence of naked ovules. BENTHAM and HOOKSER (1862-1883) consider them equivalent to dicotyledons and monocotyledons and placed between these two groups of angiosperm. They recognized three classes of gymnosperm, Cyacadaceae, coniferac and gnetaceae. Later ENGLER (1889) created a group Gnikgoales to accommodate the genus giankgo. Van Tieghem (1898) treated Gymnosperm as one of the two subdivision of spermatophyte. To accommodate the fossil members three more classes- Pteridospermae, Cordaitales, and Bennettitales where created. Coulter and chamberlain (1919), Engler and Prantl (1926), Rendle (1926) and other considered Gymnosperm as a division of spermatophyta, Phanerogamia or Embryoptyta and they further divided them into seven orders: - i) Cycadofilicales ii) Cycadales iii) Bennettitales iv) Ginkgoales v) Coniferales vi) Corditales vii) Gnetales On the basis of wood structure steward (1919) divided Gymnosperm into two classes: - i) Manoxylic ii) Pycnoxylic The various classification of Gymnosperm proposed by various workers are as follows: - i) Sahni (1920): - He recognized two sub-divison in gymnosperm: - a) Phylospermae b) Stachyospermae BOTANY PG SEMESTER – II, PAPER –V BOT521: Taxonomy and Diversity of seed plants ii) Classification proposed by chamber lain (1934): - He divided Gymnosperm into two divisions: - a) Cycadophyta b) Coniterophyta iii) Classification proposed by Tippo (1942):- He considered Gymnosperm as a class of the sub- phylum pteropsida and divided them into two sub classes:- a) Cycadophyta b) Coniferophyta iv) D.
    [Show full text]