DOCSLIB.ORG

Seasonal Effects of Heavy Metals on the Date Mussel Lithophaga Lithophaga (Mollusca:Bivalvia) at Eastern Harbor, Alexandria, Egypt

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Seasonal Effects of Heavy Metals on the Date Mussel Lithophaga Lithophaga (Mollusca:Bivalvia) at Eastern Harbor, Alexandria, Egypt Abd-Ellah et al., Swed J BioSci Res 2020; 1(1): 62 - 77. DOI: https://doi.org/10.51136/sjbsr.2020.62.77 Research Paper Seasonal effects of heavy metals on the date mussel Lithophaga lithophaga (Mollusca:Bivalvia) at Eastern harbor, Alexandria, Egypt Shahenaz M. Abd-Ellah1*, Soheir El-Sherif2, Rehab El-Morshedy2 1Department of Biological & Geological Sciences, Faculty of Education, Alexandria University, Egypt, 2Department of Zoology, Faulty of Science,, Alexandria University, Egypt. *Corresponding author: [email protected] Received: 20 October 2020 Accepted : 05 November 2020 Published online : 15 November 2020 Abstract: The edible mussel Lithophaga lithophaga is considered as one of the most important human food sources in Alexandria, Mediterranean Sea. The present study is designed to determine the seasonal bioaccumulation levels of Cd, Co and Pb in the whole soft tissues as well as different tissues of Lithophaga lithophaga. Results revealed that the seasonal bioaccumulation levels of Cd, Co and Pb in date mussel were below the permissible limits or other reported values from other regions of the Mediterranean. On the other hand, the order of metals accumulation level in different tissues was as follows: digestive gland>remaining soft tissues>gonads. The present study confirmed the role of digestive gland as a concentration center for heavy metals. Moreover, total protein content and stress protein responses of the whole soft tissues were evaluated. The total protein content was arranged in the following order: summer>autumn>spring>winter. Five novel stress proteins appeared in summer. The histological and ultrastructural studies of the digestive gland of Lithophaga lithophaga collected in summer and spring showed marked histopathological alternations. Keywords: Lithophaga lithophaga, mussel, cadmium, cobalt, lead, heavy metals, seasonal bioaccumulation. Introduction Lithophaga lithophaga is a common and widely is important in a healthy and balanced diet (WHO, distributed species, usually at shallow water of the 2003). Seafood is an important source of valuable Mediterranean, of the east Atlantic from Portugal to nutrients (Aakre et al., 2019). It contains low Morocco and in the Red Sea (Legac and Hrs- cholesterol and high percentage of n-3-poly- Brenko, 1982 ; Fischer et al., 1987; Gargominy et unsaturated fatty acids, liposoluble vitamins and al., 1999) and can also be found at a depth of 8m to essential minerals; it is rich in protein (Tahvonen et 20m or more (Simunovic and Grubelic, 1992). It is al., 2000; Adeyeye, 2002; Zalloua et al., 2007; a greatly appreciated species for human Aakre et al., 2019). Seafood can contribute to consumption as seafood and it was found in seafood human exposure to heavy metals resulting from markets and fish restaurants (Gonzalez et al., 2000). consuming contaminated aquatic organisms The over-exploitation of this species resulted in the (Hashmi et al., 2002; Carvalho et al., 2005; dramatic reduction of its population and thus, it is Francesconi, 2007; Schuwerack et al., 2007; Sioen under strict protection (Galinou-Mitsoudi and et al., 2008). Increasing anthropogenic activities Sinis, 1994; Colletti et al., 2020). It was proposed in have made heavy metals pollution in aquatic several international forums as species that should ecosystem a major cause of concern in two main be protected (Fernández-Galiano, 2000). The aspects, firstly from the public health point of view species is considered among the threatened species and secondly aquatic environmental point of view, in the Mediterranean Sea and it has been protected particularly that the pollution of the marine by the Bern and the Barcelona Conventions and the ecosystem by heavy metals is a worldwide problem. Convention on International Trade of Endangered Heavy metals are one of the serious pollutant due Species (CITES), where its collection is forbidden to their persistence, toxicity and non-degradability in by law (Kefi et al., 2016). the environment (Sharshar and Gease, 1998; Tam It is globally accepted that seafood consumption and Wong, 2000; Yuan et al.; 2004). Vymazal Copyright © 2020 Abd-Ellah et al.This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author(s) and source are credited. Abd-Ellah et al., Swed J BioSci Res 2020; 1(1): 62 - 77. DOI: https://doi.org/10.51136/sjbsr.2020.62.77 (1995) stated that the most important heavy metals Mediterranean Sea through two openings: El- from the point of view of water pollution are Cd, Co, Boughaz and El-Silsila (El-Geziry et al., 2007). Cu, Cr, Fe, Pb, Hg, Ni and Zn, some of these metals (Cu, Zn, Fe and Co) are essential for living Sampling organisms but become toxic at higher In each season, 30 sexually mature mussels, concentrations, other metals are non-essential and nearly of the same size and weight, were collected toxic even at relatively low concentrations (Pb, Cd (10 for the determination of Cd, Co and Pb and Hg). The heavy metals that constitute a great concentration; 5 for biochemical studies; 5 for threat to public health include Hg, Pb and Cd which electrophoretic studies and 10 for histopathological are potent toxicants to humans. Their studies). bioaccumulation in tissues of seafood leads to intoxication causing cellular and tissue damage, Metal analysis decreased fertility, cell death and dysfunction of a Heavy metals Cd, Co and Pb were analyzed in variety of organs and death (Fatoki and water samples and mussels tissues using graphite Mathabatha, 2004; Khan et al., 2019). furnace atomic absorption spectroscopy (Perkin- The rights of all individuals to a safe and Elmer model 2380) under the recommended adequate diet were expressed at the World Health conditions of Bernhard (1976). Organization Forum in 2007 which led to the Beijing Declaration (WHO, 2007). To document Seawater analysis seafood safety, information on the status of infective Seawater samples were collected seasonally organism, drugs residues and undesired chemical during L. lithophaga sampling. The metals elements is considered necessary (Nghia et al., concentration in the seawater was determined 2009). Determination of chemical quality of aquatic according to Eaton (1976). It was expressed as organisms consumed as seafood, particularly their μg/L. content of heavy metals, are extremely important to human health. The accumulation of these metals in Tissues analysis aquatic animals should be monitored regularly to The whole soft tissues of 5 mussels as well as the check animal health in view of the quality of public digestive gland, the gonads and the remaining soft food supplies. In many African countries direct tissues of other 5 mussels were prepared individually consumption of seafood without quality control are according to the technique of Campbell and Plank frequently due to the poverty (Martin and (1998) and they were then analyzed. Heavy metals Griswold, 2009; Morais et al., 2012; Tamele and concentrations were expressed in µg/g wet weight. Loureiro , 2020). The present study is concerned with monitoring Biochemical studies the quality of L. lithophaga as safe seafood through Determination of the total protein content determination of the seasonal bioaccumulation level The whole soft tissues of mussels were of Cd, Co and Pb in the whole soft tissues. homogenized with physiological saline and the total Additionally, the following points were considered: protein was determined seasonally by the method i) the bioaccumulation levels of Cd, Co and Pb in described by Weichselbaum (1946). different tissues, ii) the determination of the biochemical impact of the previously mentioned Electrophoretic studies metals on the total protein content, iii) the The stress protein response was investigated by determination of the stress proteins response, vi) the polyacrylamide gel electrophoresis. The whole soft investigation of the effects of these metals on the tissues of 5 mussels were homogenized in a mortar histological structure of digestive gland . using 0.05M Tris-HCL buffer (pH 6.8), then the homogenates were centrifuged at 10 000 x g for 15 Materials and methods minutes. The supernatant was taken and used for gel Study area electrophoresis analysis. Sodium dodecyl sulphate The East harbor of Alexandria was chosen as a polyacrylamide gel electrophoresis (SDS-PAGE) station from which samples were collected. It was carried out using the discontinuous buffer occupies the central part of the coast of Alexandria system described by Laemmli (1970). and covers an area of about 2.8 km (Said and Maiyza, 1987). The harbor is connected to the Histological studies of the digestive gland 63 Abd-Ellah et al., Swed J BioSci Res 2020; 1(1): 62 - 77. DOI: https://doi.org/10.51136/sjbsr.2020.62.77 For light microscopic examination the specimens of the digestive gland were fixed in 10% formaldehyde for 24 hours, dehydrated in alcohol, cleared in xylene and embedded in paraffin wax. Sections of 5µ thickness were stained with haematoxylin and eosin and were critically examined. Ultrastructural studies of the digestive gland Dissection of soft tissues were performed at (a) formaline-glutraldehyde fixative (4F1G) and very small blocks (1mm3) of the digestive gland were fixed. Sectioning was performed by using a glass knife on LKB ultramicrotome. The ultrathin sections (50 nm) were either pale gold or silver interference color and were picked upon 200 mesh naked copper grids. The ultrathin sections were stained twice by seawater (µg/l) in in uranyl acetate and lead citrate and examined by Jeol 100 CX Electron Microscope. metals Mean of concentration of heavy Statistical analysis Data of metal analysis and total protein content (b) were statistically analyzed using analysis of variance and least significant difference LSD according to Fig. (1). The mean concentrations (µg/l) of the different heavy metals in the collected seawater samples showing (a) the level of Snedecor and Cochran (1981). All comparisons for their accumulation and (b) their seasonal variations at the statistical significance were made at p=0.05.
Load more

Recommended publications
  • Foot Abnormalities in Venericardia Antiquata and Venus Verrucosa from the Bizerte Lagoon Complex
    e Rese tur arc ul h c & a u D q e A v e f l o o Béjaoui et al., J Aquac Res Development 2016, 7:7 l p a m n Journal of Aquaculture r e u n DOI: 10.4172/2155-9546.1000434 o t J ISSN: 2155-9546 Research & Development Research Article OpenOpen Access Access Foot Abnormalities in Venericardia antiquata and Venus verrucosa from the Bizerte Lagoon Complex (Northern Tunisia): Hydrodynamics and Sediment Texture Inductions Jihen Maâtoug Béjaoui, Ferdaous Jaafar Kefi, Anwar Mleiki and Najoua Trigui El Menif* Faculty of Sciences of Bizerte (FSB), Laboratory of Environment Biomonitoring, University of Carthage, Bizerte, Tunisia Abstract The Examination of the soft part of the two bivalve species Venericardia antiquata (Linnaeus 1758) and Venus verrucosa (Linnaeus 1758), that occur together in northern coast of Tunisia, allowed us to discover for the first time the presence of morphological abnormalities affecting the foot of many individuals (annual rate of 31.6%). The presence of a developed byssus was also detected in some specimens of V. antiquata. A classification scale of this malformation, established depending on the degree of this anomaly, showed six initial types that evolve to form two or three feet, at the posterior and/or anterior sides of the animal. In order to determine the causes of this malformation, experiments of transplantation were carried out. Specimens of V. verrucosa collected from Zarzouna station were transplanted in Chaâra station which is characterized by low rate of malformations, low hydrodynamics and different sediment type and vice versa. Results revealed that foot malformations degree is highly correlated with both hydrodynamics and substrate type.
    [Show full text]
  • Cop13 Prop. 35
    CoP13 Prop. 35 CONSIDERATION OF PROPOSALS FOR AMENDMENT OF APPENDICES I AND II A. Proposal Inclusion of Lithophaga lithophaga in Appendix II, in accordance with Article II, paragraph 2 (a). B. Proponents Italy and Slovenia (on behalf of the Member States of the European Community). C. Supporting statement Lithophaga lithophaga is an endolithic mussel from the family Mitilidae, which inhabits limestone rocks. This species needs specific substrate for its growth and owing to its particular biology (slow growing) it is not suitable for commercial breeding. L. lithophaga has a very distinctive and well known date-like appearance. L. lithophaga is distributed throughout the Mediterranean Sea. In the Atlantic Ocean it can be found on the Portugal coast and on the North African coast down to Senegal. It also inhabits the northern coast of Angola. The sole purpose of L. lithophaga exploitation is human consumption. It is known that the harvesting of the species from the wild for international trade has detrimental impact on the species. The collection of L. lithophaga for the purpose of trade poses a direct threat to this species due to the loss of its habitat. When L. lithophaga is harvested, the rocks it inhabits are broken into small pieces, often by very destructive methods such as pneumatic hammers and explosives. Broken rocks thus become unsuitable for colonisation by marine organisms. In addition to the direct threat to L. lithophaga, its collection reduces topographic heterogenity, macroalgal cover and epibiota. The destruction caused by L. lithophaga exploitation seriously affects littoral fish populations. The over-exploitation of L. lithophaga has caused important local ecological damage in many Mediterranean areas.
    [Show full text]
  • Speciation in the Coral-Boring Bivalve Lithophaga Purpurea: Evidence from Ecological, Biochemical and SEM Analysis
    MARINE ECOLOGY PROGRESS SERIES Published November 4 Mar. Ecol. Prog. Ser. Speciation in the coral-boring bivalve Lithophaga purpurea: evidence from ecological, biochemical and SEM analysis ' Department of Zoology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel Department of Life Sciences, Bar Ilan University, Ramat Gan 52900, Israel ABSTRACT The bonng mytil~d L~thophagapurpurea densely inhabits the scleractinian corals Cyphastrea chalc~d~cum(Forskal 1775) and Montlpora erythraea Marenzeler, 1907 In the Gulf of Ellat, Red Sea Profound differences in reproductive seasons postlarval shell morphology and isozyme poly- morphism exlst between the bivalve populatlons inhabihng the 2 coral specles wh~chshare the same reef environments Two distlnct reproductive seasons were identified in the blvalves L purpurea inhabiting A4 erythraea reproduce in summer while those In C chalcjd~cumreproduce in late fall or early winter SEM observations revealed distlnct postlarval shell morphologies of bivalves inhabiting the 2 coral hosts Postlarvae from C chalc~dcumare chalactenzed by tooth-like structures on their dissoconch, as opposed to the smooth dissoconch surface of postlarvae from M erythraea In addition, there is a significant difference (p<0 001) In prodissoconch height between the 2 bivalve populations Results obtained from isozyme electrophores~sshowed d~stinctpatterns of aminopeptidase (LAP) and esterase polymorphism, indicating genehc differences between the 2 populahons These data strongly support the hypothesis that L purpurea inhabiting the 2 coral hosts are indeed 2 d~stlnctspecles Species specificity between corals and their symbionts may therefore be more predominant than prev~ouslybeheved INTRODUCTION Boring organisms play an important role in regulat- ing the growth of coral reefs (MacCeachy & Stearn A common definition of the term species is included 1976).
    [Show full text]
  • Human Predation Along Apulian Rocky Coasts (SE Italy): Desertification Caused by Lithophaga Lithophaga (Mollusca) Fisheries
    MARINE ECOLOGY PROGRESS SERIES Published July 7 Mar. Ecol. Prog. Ser. Human predation along Apulian rocky coasts (SE Italy): desertification caused by Lithophaga lithophaga (Mollusca) fisheries 'Dipartimento di Biologia. Stazione di Biologia Marina di Porto Cesareo, Universita di Lecce, 1-73100 Lecce. Italy 'Dipartimento di Zoologia, Universita di Napoli, Via Mezzocannone 8,I-80134Napoli, Italy 31stituto Talassografico 'A. Cerruti'- CNR, Via Roma 3, 1-74100Taranto, Italy ABSTRACT: The date mussel Lithophaga lithophaga is a Mediterranean boring mollusc living in calcareous rocks. Its populations are intensely exploited by SCUBA divers, especially in southern Italy. Collection is carned out by demolition of the rocky substratum, so that human predation on date mussels causes the disappearance of the whole benthic community. The impact of this activity along the Apulian coast was evaluated by 2 surveys carried out by SCUBA diving inspection of the Salento peninsula. The Ionian coast of Apulia, from Taranto to Torre dell'orso (Otranto),was surveyed in 1990 and in 1992 by 2 series of transects (from 0 to 10 m depth, 2 km from each other), covering 210 km. Observations were transformed into an index of damage, ranging from 0 (no damage) to 1 (complete desertification). 159 km of the inspected coast are rocky. The first survey (1990) allowed us to estimate that a total of 44 km was heavily affected by this human activity (the index of damage ranging between 0.5 and l],whereas the second survey showed heavy damage along a total of 59 km. This Increase in length was accompanied by a high increase in the index of damage along parts of coast that were less intensely exploited in 1990 than in 1992.
    [Show full text]
  • NVMC Newsletter 2018-05.Pdf
    The Mineral Newsletter Meeting: May 21—NOTE! One week earlier than usual! Time: 7:45 p.m. Long Branch Nature Center, 625 S. Carlin Springs Rd., Arlington, VA Volume 59, No. 5 May 2018 Explore our website! May Meeting Program: African Gemstones In this issue … Mineral of the month: Topaz.................... p. 2 May program details ................................. p. 5 The Prez Sez .............................................. p. 6 April meeting minutes .............................. p. 6 Nametags .................................................. p. 7 Bits and pieces .......................................... p. 8 Schaefermeyer scholarships for 2018 ...... p. 9 Field trip opportunities ............................. p. 9 AFMS: Safety matters ............................... p. 10 EFMLS: Experience Wildacres! ................. p. 10 Introduction to crystallography ................ p. 12 Book review: Reading the Rocks ............... p. 13 Humor: Ogden Nash ................................. p. 14 Story of geology: Charles Lyell .................. p. 15 Upcoming events ...................................... p. 19 Smithsonian Mineral Gallery. Photo: Chip Clark. Mineral of the Month Topaz by Sue Marcus Happy May Day! Our segue from the April to the May Mineral of the Month comes through an isle in the Red Sea called Topasios Island. You might guess from that name Northern Virginia Mineral Club alone that the May mineral is topaz. members, And I hope you recall that the April mineral, olivine Please join our May speaker, Logan Cutshall, for dinner (or peridot), was found on an Egyptian island in the at the Olive Garden on May 21 at 6 p.m. Rea Sea. Ancient lapidaries and naturalists apparently used the name “topaz” for peridot! Olive Garden, Baileys Cross Roads (across from Skyline The island of Topasios (also known as St. John’s or Towers), 3548 South Jefferson St. (intersecting Zabargad Island) eventually gave its name to topaz, Leesburg Pike), Falls Church, VA although the mineral topaz is not and has never been Phone: 703-671-7507 found there.
    [Show full text]
  • Marine Boring Bivalve Mollusks from Isla Margarita, Venezuela
    ISSN 0738-9388 247 Volume: 49 THE FESTIVUS ISSUE 3 Marine boring bivalve mollusks from Isla Margarita, Venezuela Marcel Velásquez 1 1 Museum National d’Histoire Naturelle, Sorbonne Universites, 43 Rue Cuvier, F-75231 Paris, France; [email protected] Paul Valentich-Scott 2 2 Santa Barbara Museum of Natural History, Santa Barbara, California, 93105, USA; [email protected] Juan Carlos Capelo 3 3 Estación de Investigaciones Marinas de Margarita. Fundación La Salle de Ciencias Naturales. Apartado 144 Porlama,. Isla de Margarita, Venezuela. ABSTRACT Marine endolithic and wood-boring bivalve mollusks living in rocks, corals, wood, and shells were surveyed on the Caribbean coast of Venezuela at Isla Margarita between 2004 and 2008. These surveys were supplemented with boring mollusk data from malacological collections in Venezuelan museums. A total of 571 individuals, corresponding to 3 orders, 4 families, 15 genera, and 20 species were identified and analyzed. The species with the widest distribution were: Leiosolenus aristatus which was found in 14 of the 24 localities, followed by Leiosolenus bisulcatus and Choristodon robustus, found in eight and six localities, respectively. The remaining species had low densities in the region, being collected in only one to four of the localities sampled. The total number of species reported here represents 68% of the boring mollusks that have been documented in Venezuelan coastal waters. This study represents the first work focused exclusively on the examination of the cryptofaunal mollusks of Isla Margarita, Venezuela. KEY WORDS Shipworms, cryptofauna, Teredinidae, Pholadidae, Gastrochaenidae, Mytilidae, Petricolidae, Margarita Island, Isla Margarita Venezuela, boring bivalves, endolithic. INTRODUCTION The lithophagans (Mytilidae) are among the Bivalve mollusks from a range of families have more recognized boring mollusks.
    [Show full text]
  • Smithsonian Miscellaneous Collections
    SMITHSONIAN MISCELLANEOUS COLLECTIOXS. 227 AEEANGEMENT FAMILIES OF MOLLUSKS. PREPARED FOR THE SMITHSONIAN INSTITUTION BY THEODORE GILL, M. D., Ph.D. WASHINGTON: PUBLISHED BY THE SMITHSONIAN INSTITUTION, FEBRUARY, 1871. ^^1 I ADVERTISEMENT. The following list has been prepared by Dr. Theodore Gill, at the request of the Smithsonian Institution, for the purpose of facilitating the arrangement and classification of the Mollusks and Shells of the National Museum ; and as frequent applica- tions for such a list have been received by the Institution, it has been thought advisable to publish it for more extended use. JOSEPH HENRY, Secretary S. I. Smithsonian Institution, Washington, January, 1871 ACCEPTED FOR PUBLICATION, FEBRUARY 28, 1870. (iii ) CONTENTS. VI PAGE Order 17. Monomyaria . 21 " 18. Rudista , 22 Sub-Branch Molluscoidea . 23 Class Tunicata , 23 Order 19. Saccobranchia . 23 " 20. Dactjlobranchia , 24 " 21. Taeniobranchia , 24 " 22. Larvalia , 24 Class Braehiopoda . 25 Order 23. Arthropomata , 25 " . 24. Lyopomata , 26 Class Polyzoa .... 27 Order 25. Phylactolsemata . 27 " 26. Gymnolseraata . 27 " 27. Rhabdopleurse 30 III. List op Authors referred to 31 IV. Index 45 OTRODUCTIO^. OBJECTS. The want of a complete and consistent list of the principal subdivisions of the mollusks having been experienced for some time, and such a list being at length imperatively needed for the arrangement of the collections of the Smithsonian Institution, the present arrangement has been compiled for that purpose. It must be considered simply as a provisional list, embracing the results of the most recent and approved researches into the systematic relations and anatomy of those animals, but from which innova- tions and peculiar views, affecting materially the classification, have been excluded.
    [Show full text]
  • TREATISE ONLINE Number 48
    TREATISE ONLINE Number 48 Part N, Revised, Volume 1, Chapter 31: Illustrated Glossary of the Bivalvia Joseph G. Carter, Peter J. Harries, Nikolaus Malchus, André F. Sartori, Laurie C. Anderson, Rüdiger Bieler, Arthur E. Bogan, Eugene V. Coan, John C. W. Cope, Simon M. Cragg, José R. García-March, Jørgen Hylleberg, Patricia Kelley, Karl Kleemann, Jiří Kříž, Christopher McRoberts, Paula M. Mikkelsen, John Pojeta, Jr., Peter W. Skelton, Ilya Tëmkin, Thomas Yancey, and Alexandra Zieritz 2012 Lawrence, Kansas, USA ISSN 2153-4012 (online) paleo.ku.edu/treatiseonline PART N, REVISED, VOLUME 1, CHAPTER 31: ILLUSTRATED GLOSSARY OF THE BIVALVIA JOSEPH G. CARTER,1 PETER J. HARRIES,2 NIKOLAUS MALCHUS,3 ANDRÉ F. SARTORI,4 LAURIE C. ANDERSON,5 RÜDIGER BIELER,6 ARTHUR E. BOGAN,7 EUGENE V. COAN,8 JOHN C. W. COPE,9 SIMON M. CRAgg,10 JOSÉ R. GARCÍA-MARCH,11 JØRGEN HYLLEBERG,12 PATRICIA KELLEY,13 KARL KLEEMAnn,14 JIřÍ KřÍž,15 CHRISTOPHER MCROBERTS,16 PAULA M. MIKKELSEN,17 JOHN POJETA, JR.,18 PETER W. SKELTON,19 ILYA TËMKIN,20 THOMAS YAncEY,21 and ALEXANDRA ZIERITZ22 [1University of North Carolina, Chapel Hill, USA, [email protected]; 2University of South Florida, Tampa, USA, [email protected], [email protected]; 3Institut Català de Paleontologia (ICP), Catalunya, Spain, [email protected], [email protected]; 4Field Museum of Natural History, Chicago, USA, [email protected]; 5South Dakota School of Mines and Technology, Rapid City, [email protected]; 6Field Museum of Natural History, Chicago, USA, [email protected]; 7North
    [Show full text]
  • Os Nomes Galegos Dos Moluscos 2020 2ª Ed
    Os nomes galegos dos moluscos 2020 2ª ed. Citación recomendada / Recommended citation: A Chave (20202): Os nomes galegos dos moluscos. Xinzo de Limia (Ourense): A Chave. https://www.achave.ga /wp!content/up oads/achave_osnomesga egosdos"mo uscos"2020.pd# Fotografía: caramuxos riscados (Phorcus lineatus ). Autor: David Vilasís. $sta o%ra est& su'eita a unha licenza Creative Commons de uso a%erto( con reco)ecemento da autor*a e sen o%ra derivada nin usos comerciais. +esumo da licenza: https://creativecommons.org/ icences/%,!nc-nd/-.0/deed.g . Licenza comp eta: https://creativecommons.org/ icences/%,!nc-nd/-.0/ ega code. anguages. 1 Notas introdutorias O que cont!n este documento Neste recurso léxico fornécense denominacións para as especies de moluscos galegos (e) ou europeos, e tamén para algunhas das especies exóticas máis coñecidas (xeralmente no ámbito divulgativo, por causa do seu interese científico ou económico, ou por seren moi comúns noutras áreas xeográficas) ! primeira edición d" Os nomes galegos dos moluscos é do ano #$%& Na segunda edición (2$#$), adicionáronse algunhas especies, asignáronse con maior precisión algunhas das denominacións vernáculas galegas, corrixiuse algunha gralla, rema'uetouse o documento e incorporouse o logo da (have. )n total, achéganse nomes galegos para *$+ especies de moluscos A estrutura )n primeiro lugar preséntase unha clasificación taxonómica 'ue considera as clases, ordes, superfamilias e familias de moluscos !'uí apúntanse, de maneira xeral, os nomes dos moluscos 'ue hai en cada familia ! seguir
    [Show full text]
  • High Seas Mediterranean Marine Reserves: a Case Study for the Southern Balearics and the Sicilian Channel
    High Seas Mediterranean Marine Reserves: a case study for the Southern Balearics and the Sicilian Channel A briefing to the CBD’s Expert workshop on scientific and technical guidance on the use of biogeographic classification systems and identification of marine areas beyond national jurisdiction in need of protection Ottawa, 29 September–2 October 2009 Greenpeace International August 2009 Table of Contents Table of Contents...........................................................................................................2 Abbreviations and Acronyms ........................................................................................4 Executive Summary.......................................................................................................5 1. Introduction................................................................................................................8 2. Existing research on the areas and availability of information................................10 3. Southern Balearics ...................................................................................................11 3.1 Area description.................................................................................................11 3.1.1 Main topographic features..........................................................................11 3.1.2. Currents and nutrients circulation system.................................................12 3.2 Topographic Features of Remarkable Biological relevance..............................14 3.2.1. Seamounts
    [Show full text]
  • Juvenile Mortality in Benthic Marine Invertebrates
    MARINE ECOLOGY PROGRESS SERIES Vol. 146: 265-282, 1997 Published January 30 Mar Ecol Prog Ser REVIEW Juvenile mortality in benthic marine invertebrates Louis A. Gosselin*,Pei-Yuan Qian Department of Biology, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong ABSTRACT Th~rtyyears ago Thorson (1966 Neth J Sea Res 3 267-293) calculated that juvenile mor- tallty in manne bivalves could exceed 98 6% Subsequently juvenile mortality rates have been assumed to be high and to influence the evolution of life history traits However there have been no attempts to establish whether high luvenile mortality IS common or to determine if lnterspecific trends in luven~lemortality exist To address th~sIssue we revlewed 30 studies of age-specif~cmortality among bivalves, gastropods, barnacles ascid~ans,bryozoans and echinoderms High juvenile mortality is widespread among benthic marlne Invertebrates with 20 of the 30 stud~esreporting levels of luve- n~lemortal~ty >90% Mortal~tyis part~cularlyh~gh during the first moments of luvenile life and can exceed 30% during the f~rstday Pool~ngsurv~vorship data from all species revealed a general trend with survivorsh~pdecreasing exponentially during the first days or weeks of juvenile life until by the age of 4 mo, virtually all cohorts were reduced to <20% of their ~nitialnumbers ~nortalityremained low thereafter We suggest that extreme vulnerability at the onset of luvenile life is a shared tra~tthat is largely responsible for the surv~vorshiptrend Natural variation within this trend
    [Show full text]
  • Densities of the Endolithic Bivalve Lithophaga Lessepsiana (Vaillant, 1865) in Pocillopora Damicornis, Solitary Islands Marine Park, Northern NSW, Australia
    Molluscan Research 31(1): 42–46 ISSN 1323-5818 http://www.mapress.com/mr/ Magnolia Press Densities of the endolithic bivalve Lithophaga lessepsiana (Vaillant, 1865) in Pocillopora damicornis, Solitary Islands Marine Park, northern NSW, Australia STEPHEN D. A. SMITH National Marine Science Centre, Southern Cross University, PO Box 4321, Coffs Harbour, New South Wales, 2450, Australia. Email: [email protected] Abstract The Solitary Islands Marine Park is positioned in a transition zone between tropical and temperate regions and consequently supports a range of taxa with different biogeographic affinities. Driven by variable influence of the East Australian Current, there is increasing representation of tropical taxa along a cross-shelf gradient (inshore to offshore). Patterns in the population of the endolithic bivalve Lithophaga lessepsiana were examined by sampling host corals (Pocillopora damicornis) across the cross-shelf gradient and were more broadly contextualised by comparisons with samples from Heron Island. Contrary to pre- dictions based on studies on low latitude reefs, where densities are higher close to shore, these increased with increasing dis- tance from the coast. Densities were almost an order of magnitude higher at Heron Island than in the Solitary Islands Marine Park. These patterns indicate that factors other than nutrient load and temperature primarily determine L. lessepsiana densities over the scales of this study. These are likely to include larval supply, colony morphology and availability of larval settlement sites within individual coral colonies. Key words: bioerosion, boring bivalve, colony morphology, cross-shelf gradient, high latitude reefs, Bivalvia, Mytilidae Introduction SIMP where it occurs in association with Pocillopora damicornis (Linnaeus, 1758), one of the dominant coral Scleractinian corals are a dominant feature of benthic species in local coral communities (Veron et al.
    [Show full text]