Protist Diversity and Geographical Distribution

Transcription

1 Protist Diversity and Geographical Distribution

2 TOPICS IN BIODIVERSITY AND CONSERVATION Volume 8

3 Protist Diversity and Geographical Distribution Edited by W. Foissner and David L. Hawksworth Reprinted from Biodiversity and Conservation, volume 17:2 (2008) 123

4 Editors Prof. Dr. W. Foissner Universität Salzburg Naturwissenschaftliche Fakultät Inst. Zoologie Hellbrunnerstr Salzburg Austria Dr. David L. Hawksworth Universidad Complutense Fac. Farmacia Dept. Biologia Vegetal II Plaza de Ramony Cajal, Madrid Ciudad Universitaria Spain ISBN: e-isbn: DOI: / Library of Congress Control Number: Springer Science+Business Media B.V No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Cover photo: Various ciliates (Stentor polymorphus, Frontonia leucas etc.) attached to a mud particle. Printed on acid-free paper springer.com

5 Contents Protist Diversity and Geographical Distribution WILHELM FOISSNER / Protist diversity and distribution: some basic considerations THOMAS WEISSE / Distribution and diversity of aquatic protists: an evolutionary and ecological perspective SLAVA EPSTEIN and PURIFICACIÓN LÓPEZ-GARCÍA / Missing protists: a molecular prospective JAN-PETER FRAHM / Diversity, dispersal and biogeography of bryophytes (mosses) STEVEN L. STEPHENSON, MARTIN SCHNITTLER and YURI K. NOVOZHILOV / Myxomycete diversity and distribution from the fossil record to the present HENDRIK SEGERS and WILLEM H. DE SMET / Diversity and endemism in Rotifera: a review, and Keratella Bory de St Vincent JAN PAWLOWSKI and MARIA HOLZMANN / Diversity and geographic distribution of benthic foraminifera: a molecular perspective HUMPHREY GRAHAM SMITH, ANATOLY BOBROV and ENRIQUE LARA / Diversity and biogeography of testate amoebae WILHELM FOISSNER, ANNE CHAO and LAURA A. KATZ / Diversity and geographic distribution of ciliates (Protista: Ciliophora) ELLEN M. SIMON, DAVID L. NANNEY and F. PAUL DOERDER / The Tetrahymena pyriformis complex of cryptic species PETER F. M. COESEL and LOTHAR KRIENITZ / Diversity and geographic distribution of desmids and other coccoid green algae PIETER VANORMELINGEN, ELIE VERLEYEN and WIM VYVERMAN / The diversity and distribution of diatoms: from cosmopolitanism to narrow endemism F.J.R. TAYLOR, MONA HOPPENRATH and JUAN F. SALDARRIAGA / Dinoflagellate diversity and distribution JØRGEN KRISTIANSEN / Dispersal and biogeography of silica-scaled chrysophytes F.P.D. COTTERILL, KHALED AL-RASHEID and WILHELM FOISSNER / Conservation of protists: is it needed at all? v

6 Foreword -1 Conservation and biodiversity of protists The conservation of biodiversity is not just an issue of plants and vertebrates. It is the scarcely visible invertebrates and myriads of other microscopic organisms that are crucial to the maintenance of ecological processes on which all larger organisms and the composition of the atmosphere ultimately depend. Biodiversity and Conservation endeavours to take an holistic view of biodiversity, and when the opportunity arises to issue collections of papers dealing with too-often neglected groups of organisms. The protists, essentially eukaryotes that cannot be classified in the kingdoms of animals, fungi, or plants, include some of the leastknown groups of organisms on earth. They are generally treated as a separate kingdom, commonly named Protista (or Protoctista) in textbooks, but in reality they are a mixture of organisms with disparate affinities. Some authors have hypothesized that the numbers of protists are not especially large, and that many have extraordinarily wide distributions. However, the picture that unfolds from the latest studies discussed in this issue is different. There are many species with wide ranges, and proportionately more cosmopolitan species than in macroorganism groups, as a result of their long evolutionary histories, but there are also definite patterns and geographical restrictions to be found. Further, some protists are linked to host organisms as mutualists or parasites and necessarily confined to the distributions of their hosts. It is now also becoming clear that there is a great deal of cryptic speciation and clonal selection that has not been appreciated until the advent of molecular phylogenetic approaches. The traditional use of morphospecies concepts badly underestimates protistan diversity by two or three times in the case of foraminifera and ciliates. Molecular work in most protistan groups is very much in its infancy, but it seems likely that there are more than species of protists on Earth. This collection of papers makes clear that protistan groups are not a special case of limited diversity, but are very imperfectly known and merit more attention than is generally accorded to them in assessments of biodiversity. In dealing with primarily microscopic groups of organisms, conservation is a difficult task and must be two-pronged and involve both the in situ conservation of different habitat types as single-species plans are unlikely ever to be practical, and ex situ maintenance in genetic resource collections. However, focusing attention on flagship species that can serve as surrogates has the potential both to generate more basic knowledge and to act as a bioindicator of the situation in others. vii

7 viii W. Foissner et al. (eds) The 15 papers presented here consider a range of protistan groups and fundamental issues, while others focus on particular types of protists, notably slime moulds, foraminifera, ciliates, desmids, diatoms, dinoflagellates, chrysophytes, and testate amoebae; there is also one addressing dispersal and biogeography in bryophytes where there are parallel issues of wide distributional ranges. Protistan fungal groups other than slime moulds are not covered as the January 2007 issue of Biodiversity and Conservation (16(1): 1 111) included eight papers devoted to the estimation of fungal diversity. The contributions have been selected and edited by Wilhelm Foissner, a long-standing member of the Editorial Board of Biodiversity and Conservation. I am very pleased that he rose to the challenge of assembling such a thought-provoking series of papers, which should serve to highten awareness of issues in protistan diversity in biodiversity science and conservation. DAVID L. HAWKSWORTH Editor-in-Chief, Biodiversity and Conservation Universidad Complutense de Madrid, Madrid; and the Natural History Museum, London 5 January 2008