DOCSLIB.ORG

Biology and Evolution of the Mollusca Shell, Body, and Muscles

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Biology and Evolution of the Mollusca Shell, Body, and Muscles This article was downloaded by: 10.3.98.104 On: 25 Sep 2021 Access details: subscription number Publisher: CRC Press Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: 5 Howick Place, London SW1P 1WG, UK Biology and Evolution of the Mollusca Winston F. Ponder, David R. Lindberg, Juliet M. Ponder Shell, Body, and Muscles Publication details https://www.routledgehandbooks.com/doi/10.1201/9781351115667-3 Winston F. Ponder, David R. Lindberg, Juliet M. Ponder Published online on: 01 Nov 2019 How to cite :- Winston F. Ponder, David R. Lindberg, Juliet M. Ponder. 01 Nov 2019, Shell, Body, and Muscles from: Biology and Evolution of the Mollusca CRC Press Accessed on: 25 Sep 2021 https://www.routledgehandbooks.com/doi/10.1201/9781351115667-3 PLEASE SCROLL DOWN FOR DOCUMENT Full terms and conditions of use: https://www.routledgehandbooks.com/legal-notices/terms This Document PDF may be used for research, teaching and private study purposes. Any substantial or systematic reproductions, re-distribution, re-selling, loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The publisher shall not be liable for an loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. 3 Shell, Body, and Muscles In this chapter, we provide an overview of the external body on the taxon. In swimming Nautilus and crawling octopods, of molluscs, comprising the mantle, the shell and its forma- the ventral axis is rotated about 60°, while in cuttlefish and tion and growth, the epidermis and associated structures, the squid, the body axis is rotated a full 90° in its life orientation foot and operculum (of gastropods), mucoid secretions, loco- (Figure 3.1). motion, and general information on cartilage and muscles. Early molluscs were probably1 bilaterally symmetrical, Some external structures, such as the suckers found in many although the adult orientation of the anterior-posterior axis of coleoid cephalopods, are also important external features, but the early mollusc is less certain and largely depends on the as they are confined to a single group, we deal with them in putative sister taxon and outgroups. If the traditional mollusc- the appropriate taxon chapter. annelid relationship is favored, the adult orientation of the early molluscan body extended along an anterior-posterior axis with a low dorsoventral axis, as in chitons, aplacopho- 3.1 BODY SYMMETRY AND AXES rans, and monoplacophorans (Figure 3.1). In most of these Molluscan body axes are complicated, and there can be up animals, the ventral and dorsal orientation of the body is to three distinct body orientations which transform dur- maintained throughout life. ing ontogeny. As described in more detail in Chapter 8, in Besides anatomical and ecological changes in body axes, most bilaterally symmetrical animals the embryonic blastula molluscan evolution has been characterised by organ asym- has an animal-vegetal polarity, and during gastrulation, the metry and displacement. The rotation of the viscera on the blastopore forms at the vegetal pole (Biggelaar et al. 2002). head-foot in gastropod larvae during torsion is a famous In deuterostomes, the blastopore becomes the anus, thus example of twisting. Numerous additional changes in body establishing the vegetal pole as the posterior (P) of the embryo axes occur in gastropods (Figure 3.2), including detorsion, and the animal pole as the anterior (A). In protostomes, the which results in the movement of the mantle cavity posteriorly initially posterior vegetal blastopore is rotated from its ini- along the right side of the body. Some ‘pulmonate’ gastropods tial position to an anterior-ventral position where it typically have a posterior opening to the modified mantle cavity (as a forms the mouth opening (Biggelaar et al. 2002). In molluscs, lung), and this cavity is lost in some other heterobranchs (see this reorientation of the embryonic A-P axis during the forma- Chapters 4 and 20). tion of the trochophore larvae is driven by cell proliferation Bivalves have also undergone considerable modification. and migration on the embryonic dorsal surface which dis- Their shell is divided into two valves, accompanied with con- places the blastopore ventrally and then anteriorly (Biggelaar siderable lateral compression, and the mantle cavity typically et al. 2002; Wanninger & Wollesen 2015). Thus, by the mol- surrounds all or most of the body. Changes in orientation luscan trochophore stage, the original embryonic A-P axis is largely result from byssal, as in mussels, or cement attach- no longer linear, and the originally posterior blastopore has ment, as in oysters (see Figure 3.3 and Chapter 15). shifted approximately 90° to the ventral surface. In shelled In chitons, aplacophorans, and monoplacophorans the taxa, further cell proliferation and migration resulting from viscera (visceral mass) is distributed along the body, but in the formation of the dorsal shell gland displaces the second- bivalves, it is compacted laterally and dorsally, allowing ary anal opening ventrally and anteriorly. This produces the space for an expansive mantle cavity between the enclosing characteristic U-shaped gut indicative of ano-pedal flexure shell valves. In scaphopods and cephalopods, it is elongated and obscures the original embryonic body axes. A third reori- dorsally. In Nautilus (and many fossil cephalopods such as entation of the body axes may occur after metamorphosis the ammonites) this elongated tube has been coiled to enable when the animal assumes its adult life orientation. Life (or more efficient packing of the viscera. In gastropods, the dor- ‘ecological’) orientation often differs from the anatomical sally extended body is also coiled, but usually asymmetrically axes in molluscs (Figure 3.1). Some caudofoveates burrow in into a helical coil. the sediment with the posterior end dorsal, while scaphopods burrow obliquely to near vertically in the sediment with the head and foot positioned ventrally. In living cephalopods, the ventral axis is typically rotated from 45° to 90° depending 1 Not necessarily true if Brachiozoa are the sister taxon. Downloaded By: 10.3.98.104 At: 22:14 25 Sep 2021; For: 9781351115667, chapter3, 10.1201/9781351115667-3 55 56 Biology and Evolution of the Mollusca Polyplacophora Monoplacophora Aplacophora Scaphopoda Gastropoda Bivalvia Cephalopoda dorso-ventral axis of body gut antero-posterior axis of body, including viscera FIGURE 3.1 Anatomical axes in Mollusca. All animals in life orientation. Some aplacophorans are buried in an inclined or near vertical orientation, others lie horizontally. Original. Patellid (Patellogastropod) Vermetid Early planispiral (Caenogastropod) gastropod Trochid (Vetigastropod) Olivid (Caenogastropod) Heteropod Cephalaspidian (Heterobranch) Doridid (Heterobranch) (Caenogastropod) --- dorso-ventral axis --- axis of volution --- life-orientation axis FIGURE 3.2 Axis of symmetry in Gastropoda showing body and shell axes relative to life orientation. Redrawn and modified from Morton, J.E. and Yonge, C.M., Classification and structure of the Mollusca, pp. 1–58, in K.M. Wilbur and Yonge, C.M., Physiology of Mollusca, Vol. 1, Academic Press, New York, 1964. Downloaded By: 10.3.98.104 At: 22:14 25 Sep 2021; For: 9781351115667, chapter3, 10.1201/9781351115667-3 Shell, Body, and Muscles 57 INFAUNAL EPIFAUNAL Mytilid (Pteriomorphia) Pteriid (Pteriomorphia) Venerid (Heterodonta) Solenid (Heterodonta) Pectinid (Pteriomorphia) --- dorsoventral axis --- anteroposterior axis Ostreid (Pteriomorphia) FIGURE 3.3 Axes of symmetry in bivalves. Original. 3.2 SHELLS AND SPICULES single shell (univalved), and the shell is secondarily lost in some members of the latter two groups. Molluscan shells have attracted the interest of a wide range of While most gastropods are univalved, a few secrete scientists from many disparate disciplines as well as natural- an accessory shell valve after the primary shell is formed ists, artists and collectors, and the public. (e.g., hipponicids and bivalved sacoglossans). Like the oper- A calcium carbonate shell or spicules is the most obvious culum, these second shells are not true valves because they molluscan marker. Whether these shells were formed from are not secreted by the shell gland. fused spicules or not is still debated (see Chapter 13). In living In aplacophorans, the body is covered by spicules embed- molluscs, only aplacophorans exclusively have spicules, while ded in a cuticle covering the epidermis. A cuticle also cov- chitons have eight shell plates surrounded by a girdle covered ers the dorsal surface of chitons and the girdle ornamentation with spicules, scales, or hairs. (spines, scales) is embedded in it, and in some taxa it is devel- The earliest putative mollusc shells (Rostroconchia) in the oped into hairs. Calcareous dermal spicules are also present fossil record are from the early Cambrian (535–530 mya). in some heterobranch slugs (see Chapter 20). Disarticulated plates, cap-shaped, and simple curved or The molluscan shell is a calcareous structure that covers coiled ‘shells’ are also present during this period and have some to all of the upper surface of the animal. It is generally been interpreted as being shell
Load more

Recommended publications
  • Intertidal Monitoring Report 2009/2010
    Adelaide Desalination Plant Final Intertidal Monitoring Report 2009/2010 Baring, R.J., Stewart, T. D.C. & Benkendorff, K.* School of Biological Sciences, Flinders University * Author for correspondence email: [email protected] [This document contains the final report for the seasonal Adelaide Desalination Plant Intertidal Monitoring Program undertaken by Flinders University in 2009/2010.] Table of Contents Table of Contents .............................................................................................................................. 1 Executive Summary ........................................................................................................................... 2 Introduction ...................................................................................................................................... 3 Aims and Objectives .......................................................................................................................... 4 Methods ............................................................................................................................................ 5 Sampling locations and sites ............................................................................................................. 5 Invertebrate abundance.................................................................................................................... 9 Percent cover of sessile organisms ...................................................................................................
    [Show full text]
  • Haida Gwaii Slug,Staala Gwaii
    COSEWIC Assessment and Status Report on the Haida Gwaii Slug Staala gwaii in Canada SPECIAL CONCERN 2013 COSEWIC status reports are working documents used in assigning the status of wildlife species suspected of being at risk. This report may be cited as follows: COSEWIC. 2013. COSEWIC assessment and status report on the Haida Gwaii Slug Staala gwaii in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. x + 44 pp. (www.registrelep-sararegistry.gc.ca/default_e.cfm). Production note: COSEWIC would like to acknowledge Kristiina Ovaska and Lennart Sopuck of Biolinx Environmental Research Inc., for writing the status report on Haida Gwaii Slug, Staala gwaii, in Canada, prepared under contract with Environment Canada. This report was overseen and edited by Dwayne Lepitzki, Co-chair of the COSEWIC Molluscs Specialist Subcommittee. For additional copies contact: COSEWIC Secretariat c/o Canadian Wildlife Service Environment Canada Ottawa, ON K1A 0H3 Tel.: 819-953-3215 Fax: 819-994-3684 E-mail: COSEWIC/[email protected] http://www.cosewic.gc.ca Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur la Limace de Haida Gwaii (Staala gwaii) au Canada. Cover illustration/photo: Haida Gwaii Slug — Photo by K. Ovaska. Her Majesty the Queen in Right of Canada, 2013. Catalogue No. CW69-14/673-2013E-PDF ISBN 978-1-100-22432-9 Recycled paper COSEWIC Assessment Summary Assessment Summary – May 2013 Common name Haida Gwaii Slug Scientific name Staala gwaii Status Special Concern Reason for designation This small slug is a relict of unglaciated refugia on Haida Gwaii and on the Brooks Peninsula of northwestern Vancouver Island.
    [Show full text]
  • Interior Columbia Basin Mollusk Species of Special Concern
    Deixis l-4 consultants INTERIOR COLUMl3lA BASIN MOLLUSK SPECIES OF SPECIAL CONCERN cryptomasfix magnidenfata (Pilsbly, 1940), x7.5 FINAL REPORT Contract #43-OEOO-4-9112 Prepared for: INTERIOR COLUMBIA BASIN ECOSYSTEM MANAGEMENT PROJECT 112 East Poplar Street Walla Walla, WA 99362 TERRENCE J. FREST EDWARD J. JOHANNES January 15, 1995 2517 NE 65th Street Seattle, WA 98115-7125 ‘(206) 527-6764 INTERIOR COLUMBIA BASIN MOLLUSK SPECIES OF SPECIAL CONCERN Terrence J. Frest & Edward J. Johannes Deixis Consultants 2517 NE 65th Street Seattle, WA 98115-7125 (206) 527-6764 January 15,1995 i Each shell, each crawling insect holds a rank important in the plan of Him who framed This scale of beings; holds a rank, which lost Would break the chain and leave behind a gap Which Nature’s self wcuid rue. -Stiiiingfieet, quoted in Tryon (1882) The fast word in ignorance is the man who says of an animal or plant: “what good is it?” If the land mechanism as a whole is good, then every part is good, whether we understand it or not. if the biota in the course of eons has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first rule of intelligent tinkering. -Aido Leopold Put the information you have uncovered to beneficial use. -Anonymous: fortune cookie from China Garden restaurant, Seattle, WA in this “business first” society that we have developed (and that we maintain), the promulgators and pragmatic apologists who favor a “single crop” approach, to enable a continuous “harvest” from the natural system that we have decimated in the name of profits, jobs, etc., are fairfy easy to find.
    [Show full text]
  • Status and Protection of Globally Threatened Species in the Caucasus
    STATUS AND PROTECTION OF GLOBALLY THREATENED SPECIES IN THE CAUCASUS CEPF Biodiversity Investments in the Caucasus Hotspot 2004-2009 Edited by Nugzar Zazanashvili and David Mallon Tbilisi 2009 The contents of this book do not necessarily reflect the views or policies of CEPF, WWF, or their sponsoring organizations. Neither the CEPF, WWF nor any other entities thereof, assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, product or process disclosed in this book. Citation: Zazanashvili, N. and Mallon, D. (Editors) 2009. Status and Protection of Globally Threatened Species in the Caucasus. Tbilisi: CEPF, WWF. Contour Ltd., 232 pp. ISBN 978-9941-0-2203-6 Design and printing Contour Ltd. 8, Kargareteli st., 0164 Tbilisi, Georgia December 2009 The Critical Ecosystem Partnership Fund (CEPF) is a joint initiative of l’Agence Française de Développement, Conservation International, the Global Environment Facility, the Government of Japan, the MacArthur Foundation and the World Bank. This book shows the effort of the Caucasus NGOs, experts, scientific institutions and governmental agencies for conserving globally threatened species in the Caucasus: CEPF investments in the region made it possible for the first time to carry out simultaneous assessments of species’ populations at national and regional scales, setting up strategies and developing action plans for their survival, as well as implementation of some urgent conservation measures. Contents Foreword 7 Acknowledgments 8 Introduction CEPF Investment in the Caucasus Hotspot A. W. Tordoff, N. Zazanashvili, M. Bitsadze, K. Manvelyan, E. Askerov, V. Krever, S. Kalem, B. Avcioglu, S. Galstyan and R. Mnatsekanov 9 The Caucasus Hotspot N.
    [Show full text]
  • Soil Calcium Availability Influences Shell Ecophenotype Formation in the Sub-Antarctic Land Snail, Notodiscus Hookeri
    Soil Calcium Availability Influences Shell Ecophenotype Formation in the Sub-Antarctic Land Snail, Notodiscus hookeri Maryvonne Charrier1*, Arul Marie2, Damien Guillaume3, Laurent Bédouet4, Joseph Le Lannic5, Claire Roiland6, Sophie Berland4, Jean-Sébastien Pierre1, Marie Le Floch6, Yves Frenot7, Marc Lebouvier8 1 Université de Rennes 1, Université Européenne de Bretagne, UMR CNRS 6553, Campus de Beaulieu, Rennes, France, 2 Muséum National d’Histoire Naturelle, Plateforme de Spectrométrie de Masse et de Protéomique, UMR CNRS 7245, Département Régulation Développement et Diversité Moléculaire, Paris, France, 3 Université de Toulouse, Observatoire Midi-Pyrénées, Géosciences Environnement Toulouse, UMR 5563 (CNRS/UPS/IRD/CNES), Toulouse, France., 4 Muséum National d’Histoire Naturelle, Biologie des Organismes et Ecosystèmes Aquatiques, UMR CNRS 7208 / IRD 207, Paris, France, 5 Université de Rennes 1, Université Européenne de Bretagne, Service Commun de Microscopie Electronique à Balayage et micro-Analyse, Rennes, France, 6 Université de Rennes 1, Université Européenne de Bretagne, Sciences Chimiques de Rennes, UMR CNRS 6226, Campus de Beaulieu, Rennes, France, 7 Institut Polaire Français Paul Émile Victor, Technopôle Brest-Iroise, Plouzané, France, 8 Université de Rennes 1, Université Européenne de Bretagne, UMR CNRS 6553, Station Biologique, Paimpont, France Abstract Ecophenotypes reflect local matches between organisms and their environment, and show plasticity across generations in response to current living conditions. Plastic responses in shell morphology and shell growth have been widely studied in gastropods and are often related to environmental calcium availability, which influences shell biomineralisation. To date, all of these studies have overlooked micro-scale structure of the shell, in addition to how it is related to species responses in the context of environmental pressure.
    [Show full text]
  • E Urban Sanctuary Algae and Marine Invertebrates of Ricketts Point Marine Sanctuary
    !e Urban Sanctuary Algae and Marine Invertebrates of Ricketts Point Marine Sanctuary Jessica Reeves & John Buckeridge Published by: Greypath Productions Marine Care Ricketts Point PO Box 7356, Beaumaris 3193 Copyright © 2012 Marine Care Ricketts Point !is work is copyright. Apart from any use permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission of the publisher. Photographs remain copyright of the individual photographers listed. ISBN 978-0-9804483-5-1 Designed and typeset by Anthony Bright Edited by Alison Vaughan Printed by Hawker Brownlow Education Cheltenham, Victoria Cover photo: Rocky reef habitat at Ricketts Point Marine Sanctuary, David Reinhard Contents Introduction v Visiting the Sanctuary vii How to use this book viii Warning viii Habitat ix Depth x Distribution x Abundance xi Reference xi A note on nomenclature xii Acknowledgements xii Species descriptions 1 Algal key 116 Marine invertebrate key 116 Glossary 118 Further reading 120 Index 122 iii Figure 1: Ricketts Point Marine Sanctuary. !e intertidal zone rocky shore platform dominated by the brown alga Hormosira banksii. Photograph: John Buckeridge. iv Introduction Most Australians live near the sea – it is part of our national psyche. We exercise in it, explore it, relax by it, "sh in it – some even paint it – but most of us simply enjoy its changing modes and its fascinating beauty. Ricketts Point Marine Sanctuary comprises 115 hectares of protected marine environment, located o# Beaumaris in Melbourne’s southeast ("gs 1–2). !e sanctuary includes the coastal waters from Table Rock Point to Quiet Corner, from the high tide mark to approximately 400 metres o#shore.
    [Show full text]
  • Marine Snails of the Genus Phorcus: Biology and Ecology of Sentinel Species for Human Impacts on the Rocky Shores
    DOI: 10.5772/intechopen.71614 Provisional chapter Chapter 7 Marine Snails of the Genus Phorcus: Biology and MarineEcology Snails of Sentinel of the Species Genus Phorcusfor Human: Biology Impacts and on the EcologyRocky Shores of Sentinel Species for Human Impacts on the Rocky Shores Ricardo Sousa, João Delgado, José A. González, Mafalda Freitas and Paulo Henriques Ricardo Sousa, João Delgado, José A. González, MafaldaAdditional information Freitas and is available Paulo at Henriques the end of the chapter Additional information is available at the end of the chapter http://dx.doi.org/10.5772/intechopen.71614 Abstract In this review article, the authors explore a broad spectrum of subjects associated to marine snails of the genus Phorcus Risso, 1826, namely, distribution, habitat, behaviour and life history traits, and the consequences of anthropological impacts, such as fisheries, pollution, and climate changes, on these species. This work focuses on discussing the ecological importance of these sentinel species and their interactions in the rocky shores as well as the anthropogenic impacts to which they are subjected. One of the main anthro- pogenic stresses that affect Phorcus species is fisheries. Topshell harvesting is recognized as occurring since prehistoric times and has evolved through time from a subsistence to commercial exploitation level. However, there is a gap of information concerning these species that hinders stock assessment and management required for sustainable exploi- tation. Additionally, these keystone species are useful tools in assessing coastal habitat quality, due to their eco-biological features. Contamination of these species with heavy metals carries serious risk for animal and human health due to their potential of biomag- nification in the food chain.
    [Show full text]
  • On the Distribution and Food Preferences of Arion Subfuscus (Draparnaud, 1805)
    Vol. 16(2): 61–67 ON THE DISTRIBUTION AND FOOD PREFERENCES OF ARION SUBFUSCUS (DRAPARNAUD, 1805) JAN KOZ£OWSKI Institute of Plant Protection, National Research Institute, W³adys³awa Wêgorka 20, 60-318 Poznañ, Poland (e-mail: [email protected]) ABSTRACT: In recent years Arion subfuscus (Drap.) is increasingly often observed in agricultural crops. Its abun- dance and effect on winter oilseed rape crops were studied. Its abundance was found to be much lower than that of Deroceras reticulatum (O. F. Müll.). Preferences of A. subfuscus to oilseed rape and 19 other herbaceous plants were determined based on multiple choice tests in the laboratory. Indices of acceptance (A.I.), palat- ability (P.I.) and consumption (C.I.) were calculated for the studied plant species; accepted and not accepted plant species were identified. A. subfuscus was found to prefer seedlings of Brassica napus, while Chelidonium maius, Euphorbia helioscopia and Plantago lanceolata were not accepted. KEY WORDS: Arion subfuscus, abundance, oilseed rape seedlings, herbaceous plants, acceptance of plants INTRODUCTION Pulmonate slugs are seroius pests of plants culti- common (RIEDEL 1988, WIKTOR 2004). It lives in low- vated in Poland and in other parts of western and cen- land and montane forests, shrubs, on meadows, tral Europe (GLEN et al. 1993, MESCH 1996, FRANK montane glades and sometimes even in peat bogs. Re- 1998, MOENS &GLEN 2002, PORT &ESTER 2002, cently it has been observed to occur synanthropically KOZ£OWSKI 2003). The most important pest species in such habitats as ruins, parks, cemeteries, gardens include Deroceras reticulatum (O. F. Müller, 1774), and and margins of cultivated fields.
    [Show full text]
  • The Malacological Society of London
    ACKNOWLEDGMENTS This meeting was made possible due to generous contributions from the following individuals and organizations: Unitas Malacologica The program committee: The American Malacological Society Lynn Bonomo, Samantha Donohoo, The Western Society of Malacologists Kelly Larkin, Emily Otstott, Lisa Paggeot David and Dixie Lindberg California Academy of Sciences Andrew Jepsen, Nick Colin The Company of Biologists. Robert Sussman, Allan Tina The American Genetics Association. Meg Burke, Katherine Piatek The Malacological Society of London The organizing committee: Pat Krug, David Lindberg, Julia Sigwart and Ellen Strong THE MALACOLOGICAL SOCIETY OF LONDON 1 SCHEDULE SUNDAY 11 AUGUST, 2019 (Asilomar Conference Center, Pacific Grove, CA) 2:00-6:00 pm Registration - Merrill Hall 10:30 am-12:00 pm Unitas Malacologica Council Meeting - Merrill Hall 1:30-3:30 pm Western Society of Malacologists Council Meeting Merrill Hall 3:30-5:30 American Malacological Society Council Meeting Merrill Hall MONDAY 12 AUGUST, 2019 (Asilomar Conference Center, Pacific Grove, CA) 7:30-8:30 am Breakfast - Crocker Dining Hall 8:30-11:30 Registration - Merrill Hall 8:30 am Welcome and Opening Session –Terry Gosliner - Merrill Hall Plenary Session: The Future of Molluscan Research - Merrill Hall 9:00 am - Genomics and the Future of Tropical Marine Ecosystems - Mónica Medina, Pennsylvania State University 9:45 am - Our New Understanding of Dead-shell Assemblages: A Powerful Tool for Deciphering Human Impacts - Sue Kidwell, University of Chicago 2 10:30-10:45
    [Show full text]
  • Nudipleura Bathydorididae Bathydoris Clavigera AY165754 2064 AY427444 1383 AF249222 445 AF249808 599
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`);D8D-S-"Q"'("%)D:":/)U&55/B.&%)&I)_"5/&%:&5&1K)"%7)</&5&1K,)</&V(&)U/%:/')\AP,) M(BC"'7S>"1%/'SD:'=)+a,)Xa333)A9%BC/%,)</'H"%K`)?>/#:/'%)4$#:'"5("%)A$#/$H,)\&BR/7)-"1);b,)>/5#CG&&5)FU,)_/':C,) >4)YbXY,)4$#:'"5("=))U&''/#G&%7/%B/)"%7)'/c$/#:#)I&')H":/'("5#)#C&$57)V/)"77'/##/7):&)!=*=)d/H"(5e)R"%&f"&'(=$S :&RK&="B=gGh) 7&33'+8+#1-.9)"#:/.8-;/#<) =-*'+)7>?)8$B5/&.7/)#/c$/%B/#)&I)G'(H/'#)$#/7)I&')"HG5(iB".&%)"%7)#/c$/%B(%1 =-*'+)7@?)<"#:'&G&7)#G/B(/#)"%7)#/c$/%B/#)$#/7)(%):C/)GCK5&1/%/.B)'/B&%#:'$B.&%)&I)/$:CK%/$'"%)B5"7/#)(%B5$7(%1) M(%1(B$5&(7/" A"$&.+)7>?)M46A\):'//#)V"#/7)&%)I&$'S1/%/)7":"#/:)T(:C&$:)&%/)&I):T&)H"g&')%$7(G5/$'"%)#$VB5"7/#e)d"h)8$7(V'"%BC(") d!"#$%&'()*+"%7),-.)/)&"h)"%7)dVh)_5/$'&V'"%BC&(7/")d0.-1('2("34$1*+"%7)5'/#$'/6*'3)"h= A"$&.+)7@?)O(H/SB"5(V'":/7)-J4DO):'//#)T(:C&$:)&%/)&I)I&$')B"5(V'".&%)G'(&'#e)d"h)i'#:)#G5(:)T(:C(%)J$&G(#:C&V'"%BC(")"%7) dVh)#G5(:#)V/:T//%)7"(%4$)1/)"%7)8/-"9'.)"%7)dBh)V/:T//%):)39)41.'6*)*)"%7):C'//)&:C/')'(%1(B$5(7#= A"$&.+)7B?)A'-"K/#):'//)V"#/7)&%)I&$'S1/%/)7":"#/:=
    [Show full text]
  • Early Ontogeny of Jurassic Bakevelliids and Their Bearing on Bivalve Evolution
    Early ontogeny of Jurassic bakevelliids and their bearing on bivalve evolution NIKOLAUS MALCHUS Malchus, N. 2004. Early ontogeny of Jurassic bakevelliids and their bearing on bivalve evolution. Acta Palaeontologica Polonica 49 (1): 85–110. Larval and earliest postlarval shells of Jurassic Bakevelliidae are described for the first time and some complementary data are given concerning larval shells of oysters and pinnids. Two new larval shell characters, a posterodorsal outlet and shell septum are described. The outlet is homologous to the posterodorsal notch of oysters and posterodorsal ridge of arcoids. It probably reflects the presence of the soft anatomical character post−anal tuft, which, among Pteriomorphia, was only known from oysters. A shell septum was so far only known from Cassianellidae, Lithiotidae, and the bakevelliid Kobayashites. A review of early ontogenetic shell characters strongly suggests a basal dichotomy within the Pterio− morphia separating taxa with opisthogyrate larval shells, such as most (or all?) Praecardioida, Pinnoida, Pterioida (Bakevelliidae, Cassianellidae, all living Pterioidea), and Ostreoida from all other groups. The Pinnidae appear to be closely related to the Pterioida, and the Bakevelliidae belong to the stem line of the Cassianellidae, Lithiotidae, Pterioidea, and Ostreoidea. The latter two superfamilies comprise a well constrained clade. These interpretations are con− sistent with recent phylogenetic hypotheses based on palaeontological and genetic (18S and 28S mtDNA) data. A more detailed phylogeny is hampered by the fact that many larval shell characters are rather ancient plesiomorphies. Key words: Bivalvia, Pteriomorphia, Bakevelliidae, larval shell, ontogeny, phylogeny. Nikolaus Malchus [[email protected]], Departamento de Geologia/Unitat Paleontologia, Universitat Autòno− ma Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain.
    [Show full text]
  • Anuário Do Instituto De Geociências - UFRJ
    Anuário do Instituto de Geociências - UFRJ www.anuario.igeo.ufrj.br As Famílias Veneridae, Trochidae, Akeridae e Acteonidae (Mollusca), na Formação Romualdo: Aspectos Paleoecológicos e Paleobiogeográicos no Cretáceo Inferior da Bacia do Araripe, NE do Brasil The Families Veneridae, Trochidae, Akeridae and Acteonidae (Mollusca), in the Romualdo Formation: Paleoecological and Paleobiogeographic Aspects in the Lower Cretaceous of the Araripe Basin, NE of Brazil Priscilla Albuquerque Pereira1; Rita de Cassia Tardin Cassab2 & Alcina Magnólia Franca Barreto1 1Universidade Federal de Pernambuco, Centro de Tecnologia e Geociências, Departamento de Geologia, Laboratório de Paleontologia, Av. Hélio Acadêmico Ramos, s/n, Cidade Universitária, 50740-533, Recife, PE, Brasil 2 Universidade Federal do Rio de Janeiro, Instituto de Geociências, Departamento de Geologia, Avenida Athos da Silveira Ramos, 274, 21910-900, Cidade Universitária, Ilha do Fundão, s/n, Rio de Janeiro, Rio de Janeiro-RJ, Brasil E-mail: [email protected]; [email protected]; [email protected] Recebido em: 18/07/2018 Aprovado em: 21/09/2018 DOI: http://dx.doi.org/10.11137/2018_3_137_152 Resumo Moluscos fósseis na Bacia Sedimentar do Araripe são relatados desde a década de 1960, com biválvios presentes nas forma- ções Crato, Romualdo e gastrópodos, restritos a Formação Romualdo. A identiicação e descrição desses moluscos tem auxiliado na reconstituição paleoambiental da Formação Romualdo (Aptiano-Albiano) e na interpretação da rota de incursão marinha que aponta para inluência do mar de Tétis na bacia. Este trabalho, descreve e ilustra fósseis coletados nas localidades de Zé Gomes, Cedro/ Tabuleiro e Santo Antônio município de Exu, Pernambuco, pontuando a paleoecologia e a distribuição paleogeográica dos gêneros, além de observar as ainidades faunísticas entre as formaçõe Romualdo e Riachuelo.
    [Show full text]