Insect Biodiversity. Science and Society. Edited by. Robert G. Foottit Agriculture and Agri-Food Canada Ottawa Ontario Canada

Transcription

1 Insect Biodiversity

2 Insect Biodiversity Science and Society Second Edition Volume I Edited by Robert G. Foottit Agriculture and Agri-Food Ottawa Ontario Peter H. Adler Clemson University Clemson South Carolina

3 This edition first published John Wiley & Sons First edition published 2009 by John Wiley & Sons Ltd All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at The right of Robert G. Foottit and Peter H. Adler to be identified as the authors of the editorial material in this work has been asserted in accordance with law. Registered Office(s) John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK Editorial Office 9600 Garsington Road, Oxford, OX4 2DQ, UK For details of our global editorial offices, customer services, and more information about Wiley products visit us at www. wiley.com. Wiley also publishes its books in a variety of electronic formats and by print-on-demand. Some content that appears in standard print versions of this book may not be available in other formats. Limit of Liability/Disclaimer of Warranty While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials or promotional statements for this work. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. Library of Congress Cataloging-in-Publication Data applied for. ISBN: Cover Design: Wiley Cover Image: A sampling of beetle diversity in the Palearctic Region. Images by Kirill Makarov Set in 10/12pt, WarnockPro by SPi Global, Chennai, India

4 v Brief Table of Contents 1 Introduction 1 2 The Importance of Insects 9 Part I Insect Biodiversity: Regional Examples 45 3 Insect Biodiversity in the Nearctic Region 47 4 Amazonian Rainforests and Their Richness and Abundance of Terrestrial Arthropods on the Edge of Extinction: Abiotic Biotic Players in the Critical Zone 65 5 Insect Biodiversity in the Afrotropical Region 93 6 Biodiversity of Australasian Insects Insect Biodiversity in the Palearctic Region 141 Part II Insect Biodiversity: Taxon Examples Biodiversity of Aquatic Insects Biodiversity of Diptera Biodiversity of Heteroptera Biodiversity of Coleoptera Biodiversity of Hymenoptera Diversity and Significance of Lepidoptera: A Phylogenetic Perspective 463 Part III Insect Biodiversity: Tools and Approaches The Science of Insect Taxonomy: Prospects and Needs 499

5 vi Brief Table of Contents 15 Insect Species Concepts and Practice Molecular Dimensions of Insect Taxonomy in the Genomics Era DNA Barcodes and Insect Biodiversity Insect Biodiversity Informatics Parasitoid Biodiversity and Insect Pest Management The Taxonomy of Crop Pests: The Aphids Adventive (Non-Native) Insects and the Consequences for Science and Society of Species that Become Invasive Biodiversity of Blood-sucking Flies: Implications for Humanity Reconciling Ethical and Scientific Issues for Insect Conservation Taxonomy and Management of Insect Biodiversity Insect Biodiversity Millions and Millions 783

6 vii Detailed Table of Contents List of Contributors xix Foreword, Second Edition xxiii Preface, First Edition xxvii Preface, Second Edition xxix Acknowledgements xxxi 1 Introduction 1 Peter H. Adler and Robert G. Foottit References 5 2 The Importance of Insects 9 Geoffrey G. E. Scudder 2.1 Diversity Ecological Role Effects on Natural Resources, Agriculture, and Human Health Insects and Advances in Science Biomechanics Genetics Developmental Biology Evolution Physiology Ecology Paleolimnology and Climate Change Insects and the Public 23 References 25 Part I Insect Biodiversity: Regional Examples 45 3 Insect Biodiversity in the Nearctic Region 47 Hugh V. Danks and Andrew B. T. Smith 3.1 Influence of Insect Biodiversity on Society in the Nearctic Region Insect Conservation Species Diversity and the State of Knowledge Assembling the Data Synopsis of Biodiversity 54

7 viii Detailed Table of Contents State of Knowledge Variations in Biodiversity Regional Variation Habitats Conclusions and Needs 58 Acknowledgments 60 References 60 4 Amazonian Rainforests and Their Richness and Abundance of Terrestrial Arthropods on the Edge of Extinction: Abiotic Biotic Players in the Critical Zone 65 Terry L. Erwin, Laura S. Zamorano and Christy J. Geraci 4.1 The Climatic Setting and Critical Zone Establishment Characterization of Typical Lowland Rainforest Composition in the Western Basin Sampling Arthropod Biodiversity in Amazonian Forests Richness of Various Lineages and Guilds General Patterns Morphospecies Richness to Biodiversity Beetles: Life Attributes Have Led to Contemporary Hyperdiversity Summary and Guide to Future Research, or Taking a Small Step into the Biodiversity Vortex 85 Acknowledgments 86 References 86 5 Insect Biodiversity in the Afrotropical Region 93 Clarke H. Scholtz and Mervyn W. Mansell 5.1 What Do We Know about Afrotropical Insects? An Information-Management Program The Role of Insects in Ecosystem Processes and as Indicators of Environmental Quality Dung Beetles as a Case Study Dung Beetles as Indicators of Regional Biodiversity Dung Beetles as Indicators of Habitat Transformation Africa-Wide Pests and Training Appropriate Taxonomists Fruit Flies as a Case Study Invasive Species of Concern in Africa African Indigenous Fruit Flies of Economic Importance Sentinel Groups Neuroptera Dung Beetles (Coleoptera: Scarabaeidae: Scarabaeinae) Conclusions 105 References Biodiversity of Australasian Insects 111 Peter S. Cranston 6.1 Australasia The Locale Some Highlights of Australasian Insect Biodiversity The Lord Howe Island Stick Insect Australasian Birdwing Conservation 115

8 Detailed Table of Contents ix 6.3 Drowning by Numbers? How Many Insect Species are in Australasia? Australia New Zealand (Aotearoa), Chatham Islands, and Subantarctic Islands New Guinea New Caledonia and the West Pacific Australasian Insect Biodiversity Overview and Special Elements Australia New Zealand New Caledonia, New Guinea, and Melanesia Threatening Processes to Australasian Insect Biodiversity Land Clearance and Alteration Introduced Animals Climate Change Australasian Biodiversity Conservation Conclusion 129 References Insect Biodiversity in the Palearctic Region 141 Boris A. Korotyaev, Alexander S. Konstantinov and Mark G. Volkovitsh 7.1 Preface: Societal Importance of Biodiversity in the Palearctic Region Introduction Geographic Position, Climate, and Zonality General Features of Palearctic Insect Biodiversity Biodiversity of Some Insect Groups in the Palearctic Biodiversity of Insect Herbivores Boundaries and Insect Biodiversity Local Biodiversity Insect Biodiversity and Habitats Insect Biodiversity and the Mountains Temporal Changes in Insect Biodiversity Insect Diversity in Major Biogeographical Divisions of the Palearctic Arctic (Circumpolar Tundra) Region Forest Regions Taiga Nemoral European and Stenopean Forests Hesperian and Orthrian Evergreen Forests Steppe (Scythian) Region Desert (Sethian) Region 183 Acknowledgments 187 References 189 Part II Insect Biodiversity: Taxon Examples Biodiversity of Aquatic Insects 205 John C. Morse 8.1 Overview of Taxa Mayflies (Ephemeroptera) 206

9 x Detailed Table of Contents Dragonflies and Damselflies (Odonata) Stoneflies (Plecoptera) Cockroaches (Blattodea) Grasshoppers and Crickets (Orthoptera) Earwigs (Dermaptera) Lice (Phthiraptera) Bugs (Hemiptera) Wasps (Hymenoptera) Hellgrammites and Alderflies (Megaloptera) Nerve winged Insects (Neuroptera) Scorpionflies (Mecoptera) Beetles (Coleoptera) Caddisflies (Trichoptera) Moths (Lepidoptera) Flies (Diptera) Species Numbers Societal Benefits and Risks Societal Benefits of Aquatic Insect Diversity in Food Webs Societal Benefits of Aquatic Insect Diversity in Biomonitoring Societal Benefits of Aquatic Insect Diversity in Fishing Societal Benefits of Aquatic Insect Diversity in Control of Noxious Weeds Societal Risks of Aquatic Insects Biodiversity Concerns for Aquatic Insects Threats to Freshwater Species of Insects Need for Biodiversity Discovery and Description of Aquatic Insects Need to Refine Definitions of Species of Aquatic Insects Need for New Generation of Aquatic Entomologists 219 References Biodiversity of Diptera 229 Gregory W. Courtney, Thomas Pape, Jeffrey H. Skevington and Bradley J. Sinclair 9.1 Overview of Taxa Lower Diptera Brachycera Lower Brachycera Empidoidea Lower Cyclorrhapha Non-calyptrate Schizophora Calyptratae Societal Importance Diptera as Plant Pests (Agriculture, Silviculture, and Floriculture) Medical and Veterinary Importance Disease transmission Myiasis Invasive Alien Diptera Diptera as a General Nuisance 249

10 Detailed Table of Contents xi Diptera in Biological Control Pollination Other Ecological Services (Scavengers and Decomposers) Diptera of Forensic, Medicolegal, and Medical Importance Diptera as Model Organisms and Research Tools Physiology and Genetics Technology Diptera in Conservation Bioindicators Vanishing Species Diptera as Part of Our Cultural Legacy 256 References Biodiversity of Heteroptera 279 Thomas J. Henry 10.1 Overview of the Heteroptera Euheteroptera Infraorder Enicocephalomorpha Infraorder Dipsocoromorpha Neoheteroptera Infraorder Gerromorpha Panheteroptera Infraorder Nepomorpha Infraorder Leptopodomorpha Infraorder Cimicomorpha Infraorder Pentatomomorpha The Importance of Heteropteran Biodiversity 311 Acknowledgments 313 References Biodiversity of Coleoptera 337 Patrice Bouchard, Andrew B. T. Smith, Hume Douglas, Matthew L. Gimmel, Adam J. Brunke and Kojun Kanda 11.1 Overview of Extant Taxa Suborders Archostemata and Myxophaga Suborder Adephaga Suborder Polyphaga Series Staphyliniformia Series Scarabaeiformia Series Elateriformia Series Derodontiformia Series Bostrichiformia Series Cucujiformia Overview of Fossil Taxa Societal Benefits and Risks Beetles of Economic Importance 357

11 xii Detailed Table of Contents Negative Effects of Beetles Positive Effects of Beetles Beetles of Cultural Importance Beetles of Medical and Legal Importance Medical Entomology Forensic Entomology Beetles as Research Tools DNA Barcoding of Beetles A North American Case Study Threatened Beetles Conclusions 395 Acknowledgments 395 References Biodiversity of Hymenoptera 419 John T. Huber 12.1 Evolution and Higher Classification Numbers of Species and Individuals Morphological and Biological Diversity Importance to Humans Food and Other Products Stings and Bites Ecological Importance Conservation Fossils Collecting, Preservation, and Study Techniques Taxonomic Diversity Symphyta Parasitica Stephanoidea Megalyroidea Trigonaloidea Mymarommatoidea Evanioidea Ichneumonoidea Cynipoidea Proctotrupoidea Platygastroidea Diaprioidea Ceraphronoidea Chalcidoidea Aculeata Chrysidoidea Vespoidea Apoidea Summary and Conclusions 446 Acknowledgments 446 References 447

12 Detailed Table of Contents xiii 13 Diversity and Significance of Lepidoptera: A Phylogenetic Perspective 463 Paul Z. Goldstein 13.1 Relevance of Lepidoptera: Science Relevance of Lepidoptera: Society Diversity and Diversification: A Clarification of Numbers and Challenges State of Lepidopteran Systematics and Phylogenetics General Overview Primitive Lepidoptera Ditrysia Tineoidea Gracillarioidea Yponomeutoidea Apoditrysia Gelechioidea Pterophoroidea Tortricoidea Cossoidea Zygaenoidea Obtectomera Macroheterocera Needs and Challenges for Advancing Lepidopteran Studies 488 Acknowledgments 489 References 489 Part III Insect Biodiversity: Tools and Approaches The Science of Insect Taxonomy: Prospects and Needs 499 Quentin D. Wheeler and Kelly B. Miller 14.1 The What and Why of Taxonomy Improving Biology s General Reference System Inter Generational Ethics Fulfilling Our Intellectual Manifest Destiny Solving Problems Model Organisms Molecular Tools of the Trade Aesthetics Creating the Vocabulary and Syntax of a Language of Biodiversity Mapping the Biosphere Insect Taxonomy: Missions and Big Questions Insect Taxonomy s Grand Challenge Questions What Is a Species? What (and How Many) Insect Species Are There? What Is the Phylogeny of Insects? What Are the Histories of Character Transformation in Insects? Where Are Insect Species Distributed? How Have Insect Distributions Changed through Time? How Can Insect Classifications and Names Be Most Predictive and Informative? 513

13 xiv Detailed Table of Contents 14.4 Transforming Insect Taxonomy Insect Taxonomy: Needs and Priorities Education Planetary Scale Projects and Virtual Species Observatories Cybertaxonomy Infrastructure Web Based Revisions, Taxon Knowledge Communities and Taxon Knowledge Banks Collection Development and Growth Integrative Insect Taxonomy Accelerating Descriptive Taxonomy (1) Inventories to collections (2) Species descriptions (3) Species tests (4) Species tests to databases (5) Collection data (6) Cladistic analysis (7 10) Phylogenetic classifications, names, and identifications (12 16) Inputs Beware Sirens of Expediency Conclusions 522 References Insect Species Concepts and Practice 527 Michael F. Claridge 15.1 Early Species Concepts Linnaeus Biological Species Concepts Agamospecies Allopatric Forms Phylogenetic Species Concepts Species Concepts and Speciation a Digression? Insect Species Practical Problems Parthenogenetic Insects Species, Host Races, and Biotypes Specific Mate Recognition and Sibling Species Conclusions 540 References Molecular Dimensions of Insect Taxonomy in the Genomics Era 547 Amanda Roe, Julian Dupuis and Felix Sperling 16.1 Opportunities in Insect Taxonomy Determination Discovery Delimitation Phylogeny Genomic Methods Sequencing Technologies 553

14 Detailed Table of Contents xv Genomic Sampling Strategies General Challenges and Considerations Data Quantity Versus Quality Phylogenetic Considerations Locus Selection Missing Data Gene Tree/Species Tree Incongruence Computational/Logistical/Bioinformatic Bottlenecks The Role of Morphology in a Post-genomic Era Conclusions 560 References DNA Barcodes and Insect Biodiversity 575 John-James Wilson, Kong-Wah Sing, Robin M. Floyd and Paul D. N. Hebert 17.1 Species Concepts and Recognition DNA Barcoding Methodology Basal Hexapod Orders Archaeognatha (Bristletails) and Zygentoma (Silverfish) Odonata (Dragonflies) Ephemeroptera (Mayflies) Orthoptera (Grasshoppers) Phasmatodea (Walking Sticks), Embioptera (Webspinners), Grylloblattodea (Icecrawlers), and Mantophasmatodea (Gladiators) Plecoptera (Stoneflies) and Dermaptera (Earwigs) Mantodea (Mantids) Blattodea (Cockroaches) and Isoptera (Termites) Psocoptera (Booklice) and Phthiraptera (Lice) Thysanoptera (Thrips) and Hemiptera (True Bugs) Hymenoptera (Wasps) Strepsiptera (Twisted-wing Parasites) Coleoptera (Beetles) Neuroptera (Lacewings), Megaloptera (Dobsonflies), and Raphidioptera (Snakeflies) Trichoptera (Caddisflies) Lepidoptera (Butterflies and Moths) Diptera (Flies) Siphonaptera (Fleas) and Mecoptera (Scorpionflies) Conclusions 584 Acknowledgments 585 References Insect Biodiversity Informatics 593 Norman F. Johnson 18.1 Biodiversity Data Technical Infrastructure Standards 597

15 xvi Detailed Table of Contents 18.4 Current Status and Impediments to Progress Prospects 600 Acknowledgments 601 References Parasitoid Biodiversity and Insect Pest Management 603 John Heraty 19.1 What Is a Parasitoid? Biodiversity and Success of Insect Parasitoids Hymenoptera (Apocrita) Phoridae Tachinidae Other Groups Where Are Parasitoids Most Diverse? Leaf mining Parasitoids and Native Landscapes Are Parasitoids More Diverse in Tropical Versus Temperate Climates? Systematics, Parasitoids, and Pest Management Molecules and Parasitoid Biodiversity Cryptic Species DNA Barcoding and Biodiversity of Parasitoids Can Molecular Markers Be Applied to Understanding Biodiversity? Summary 617 Acknowledgments 618 References The Taxonomy of Crop Pests: The Aphids 627 Gary L. Miller and Robert G. Foottit 20.1 Historical Background Economic Importance and Early Taxonomy Early Aphid Studies A North American Example Recognizing Aphid Species The Focus Becomes Finer Adventive Aphid Species Conclusions 634 References Adventive (Non-Native) Insects and the Consequences for Science and Society of Species that Become Invasive 641 Alfred G. Wheeler, Jr and E. Richard Hoebeke 21.1 Terminology Distributional Status: Native or Adventive? Global Transport: Pathways and Vectors Early History of Adventive Insects in North America Numbers, Taxonomic Composition, and Geographic Origins of Adventive Insects Impact of Adventive Insects Beneficial 656

16 Detailed Table of Contents xvii Detrimental Economic Considerations: Agriculture, Forestry, and Horticulture Crop Losses Plant Diseases and Transmission of Pathogens Implications for Animal and Human Health Ecological Impacts Ants Bees and Wasps Forest Pests Biological Control Biological Invasions and Global Climate Change Systematics, Biodiversity, and Adventive Species Concluding Thoughts 671 Acknowledgments 674 References Biodiversity of Blood-sucking Flies: Implications for Humanity 713 Peter H. Adler 22.1 Numbers and Estimates Overview of Blood-sucking Flies and Diseases Athericidae Ceratopogonidae Corethrellidae Culicidae Glossinidae Hippoboscidae Muscidae Psychodidae Rhagionidae Simuliidae Tabanidae Rationale for Biodiversity Studies of Blood-sucking Flies Biodiversity Exploration Societal Consequences of Disregarding Biodiversity Present and Future Concerns Conclusions 733 Acknowledgments 734 References Reconciling Ethical and Scientific Issues for Insect Conservation 747 Michael J. Samways 23.1 Valuing Nature Types of Value Sensitive Use of Ecosystem Services Common Good Approaches Intrinsic Value and Conservation Action 752

17 xviii Detailed Table of Contents Reconciling Values Insects and Ecosystems Interactions and Multiple Effects Insects and Food Webs Importance of Maintaining Landscape Connectance Two Challenges The Taxonomic Challenge The Challenge of Complementary Surrogates Synthesizing Deeper Values and Practical Issues Summary 760 Acknowledgments 760 References Taxonomy and Management of Insect Biodiversity 767 Ke Chung Kim 24.1 Insect Biodiversity Biodiversity Loss and Humanity Biodiversity and Taxonomy Biodiversity Inventory and Ecology Backyard Biodiversity and Sustainability Taxonomic Bottlenecks in Managing Insect Biodiversity Advancing the Science of Insect Biodiversity 776 References Insect Biodiversity Millions and Millions 783 May Berenbaum Acknowledgments 789 References 791 Index 1 (Arthropoda-Hierarchic) 793 Index 2 (Arthropoda-Alphabetic) 825 Index 3 (Non-arthropods) 849 Index 4 (General Index Terms) 855

18 xix List of Contributors Peter H. Adler Department of Plant and Environmental Sciences Clemson University Clemson South Carolina May Berenbaum Department of Entomology University of Illinois Urbana Illinois Patrice Bouchard Canadian National Collection of Insects, Arachnids and Nematodes Agriculture and Agri Food Ottawa Ontario Adam J. Brunke Canadian National Collection of Insects, Arachnids and Nematodes Agriculture and Agri Food Ottawa Ontario Michael F. Claridge School of Biosciences Cardiff University Cardiff Wales UK Gregory W. Courtney Department of Entomology Iowa State University Ames Iowa Peter S. Cranston Evolution, Ecology and Genetics Research School of Biology The Australian National University Canberra Australia Hugh V. Danks Biological Survey of Canadian Museum of Nature Ottawa Ontario Hume Douglas Canadian National Collection of Insects, Arachnids and Nematodes Agriculture and Agri Food Ottawa Ontario Julian Dupuis Department of Biological Sciences University of Alberta Edmonton Alberta

19 xx List of Contributors Terry L. Erwin Department of Entomology National Museum of Natural History Smithsonian Institution Washington DC Robin M. Floyd Wellcome Trust/MRC Stem Cell Institute University of Cambridge Cambridge UK and Centre for Biodiversity Genomics Biodiversity Institute of Ontario University of Guelph Guelph Ontario Robert G. Foottit Canadian National Collection of Insects, Arachnids and Nematodes Agriculture and Agri Food Ottawa Ontario Christy J. Geraci Department of Entomology National Museum of Natural History, Smithsonian Institution Washington DC Matthew L. Gimmel Invertebrate Zoology Santa Barbara Museum of Natural History Santa Barbara California Paul Z. Goldstein Systematic Entomology Laboratory Plant Science Institute Agriculture Research Service US Department of Agriculture c/o Smithsonian Institution Washington DC Paul D. N. Hebert Centre for Biodiversity Genomics Biodiversity Institute of Ontario University of Guelph Guelph Ontario Thomas J. Henry Systematic Entomology Laboratory Plant Science Institute Agriculture Research Service US Department of Agriculture c/o Smithsonian Institution Washington DC John Heraty Department of Entomology University of California Riverside California E. Richard Hoebeke Georgia Museum of Natural History and Department of Entomology University of Georgia Athens Georgia John T. Huber Natural Resources Canadian Forestry Service c/o Canadian National Collection of Insects, Arachnids and Nematodes Ottawa Ontario

20 List of Contributors xxi Norman F. Johnson Department of Evolution, Ecology and Organismal Biology and Department of Entomology Ohio State University Columbus Ohio Kojun Kanda Department of Biological Sciences Northern Arizona University Flagstaff Arizona Ke Chung Kim Frost Entomological Museum Department of Entomology Pennsylvania State University University Park Pennsylvania Alexander S. Konstantinov Systematic Entomology Laboratory Plant Science Institute Agriculture Research Service US Department of Agriculture c/o Smithsonian Institution Washington DC Boris A. Korotyaev Zoological Institute Russian Academy of Sciences St Petersburg Russia Mervyn W. Mansell Department of Zoology and Entomology University of Pretoria Pretoria South Africa Gary L. Miller Systematic Entomology Laboratory Plant Science Institute Agricultural Research Service US Department of Agriculture Beltsville Maryland Kelly B. Miller Department of Biology University of New Mexico Albuquerque New Mexico John C. Morse Department of Plant and Environmental Sciences Clemson University Clemson South Carolina Thomas Pape Natural History Museum of Denmark University of Copenhagen Copenhagen Denmark Amanda Roe Natural Resources Canadian Forest Service Great Lakes Forestry Centre Sault Ste. Marie Ontario Michael J. Samways Department of Conservation Ecology and Entomology Stellenbosch University Matieland South Africa

21 xxii List of Contributors Clarke H. Scholtz Department of Zoology and Entomology University of Pretoria Pretoria South Africa Geoffrey G. E. Scudder Department of Zoology University of British Columbia Vancouver British Columbia Bradley J. Sinclair Canadian National Collection of Insects and Canadian Food Inspection Agency Ottawa Plant Laboratory Entomology Ottawa Ontario Kong-Wah Sing State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming P. R. China and Institute of Biological Sciences University of Malaya Kuala Lumpur Malaysia Jeffrey H. Skevington Canadian National Collection of Insects, Arachnids and Nematodes Agriculture and Agri Food Ottawa Ontario Andrew B. T. Smith Research Division Canadian Museum of Nature Ottawa Ontario Felix Sperling Department of Biological Sciences Biological Sciences Centre University of Alberta Edmonton Alberta Mark G. Volkovitsh Zoological Institute Russian Academy of Sciences St Petersburg Russia Alfred G. Wheeler, Jr Department of Plant and Environmental Sciences Clemson University Clemson South Carolina Quentin D. Wheeler College of Environmental Science and Forestry State University of New York Syracuse New York John-James Wilson International College Beijing China Agricultural University Beijing P. R. China and Institute of Biological Sciences University of Malaya Kuala Lumpur Malaysia Laura S. Zamorano Department of Entomology National Museum of Natural History Smithsonian Institution Washington DC

22 xxiii Foreword, Second Edition Insects are the most exuberant manifestation of Earth s many and varied life forms. Their rather simple unifying body plan has become modified and adapted to produce an enormous variety of species, and insects exploit virtually all terrestrial and freshwater environments on the planet, as well as many brackish waters. However, as a paradox debated extensively a few decades ago, they are largely absent from the seas and oceans. Features such as wings and the complete metamorphosis of many species have been cited frequently as fostering this massive diversity. The success of the insects can be measured by many parameters: their long term persistence and stability of their basic patterns, the variety of higher groups (with almost 30 orders commonly recognized) and, as emphasized in this book, the wealth of species and similar entities. Each of these species has its individual biological peculiarities, ecological role, distribution, and interactions within the local community. And each may differ in habit and appearance, both from its close relatives and across its range, to reflect local influences and conditions. Every species is thus a mosaic of physical variety and genetic constitution that can lead to taxonomic and ecological ambiguity in interpreting its integrity and the ways in which it may evolve and persist. Entomologists will continue to debate the number of insect species that exist and the levels of past and likely future extinctions that edit any such estimate. The difficulties in gaining consensus have two main axes first, lack of understanding of how these entities may be recognized and categorized and, second, that many insect groups remain substantially undercollected and are poorly known. The first of these themes dominates much of this book gaining agreement over what is a species is difficult and sometimes contentious. Many taxonomists hold strong and individualistic views, molded by years of study, of the limits of species and the validity of infraspecific categories such as subspecies and races that in practice can function as evolutionarily significant units in their insect group. One widespread trend, often not appreciated fully, is that widespread generalist insect species may not persist as such as their environment changes loss of resources and fragmentation of previously extensive biotopes may cause populations to become isolated, and restricted to a limited subset of resources, such as particular host plants, on which they must then depend and specialize. Such situations may beget speciation, perhaps especially among phytophagous insects that display many examples of such localized but obligatory isolation. Populations involved commonly show haplotype differences and biological idiosyncrasies related to their local conditions, but otherwise are not easily separable. Generalist species may commonly comprise complexes of cryptic species masquerading as a single entity. Conventional typological taxonomists may tend to mirror the more conservative generalist approach, whereas other constituents (such as many butterfly collectors) may opt to recognize numerous isolated populations displaying small phenotypic variations as

23 xxiv Foreword, Second Edition distinct (specific or subspecific) taxa. Individual specialists in any large insect group are likely to occupy different positions along the gradient of lumpers to splitters in how they treat such variety, and may defend their stance energetically. Biologists and philosophers alike continue to debate the merits of the numerous species concepts, drawing on the reality quoted by one recent commentator that there are n+1 definitions of species in a room of n biologists, with the most common inference that a species is whatever a taxonomist says it is. All recognized categories, however, are dynamic. Any given figure for insect diversity (as numbers of species) is a working hypothesis, as is each of the contributing species so that complete and enduring enumeration is perhaps impossible to achieve. Documenting and cataloging insect biodiversity as a major component of Earth s life is a natural quest of human inquiry, but is not an end in itself and, importantly, is not synonymous with conserving insects or a necessary prerequisite to assuring their well being. Despite many ambiguities in projecting the actual numbers of insect species, no one would query that there are a lot, and that the various ecological processes that sustain ecosystems depend heavily on insect activity. Indeed, ecological services such as pollination, recycling of materials, and the economically important activities of predators and parasitoids are signaled increasingly as part of the rationale for insect conservation because these values can be appreciated easily through direct economic impacts. All these themes are dealt with in this book, centered on questions related to our ignorance of fundamental matters of how many are there? and how important are they?, to which the broad answers of millions and massive may incorporate considerable uncertainty; this uncertainty, however, is reduced by many of the chapters here. In any investigations of insect biodiversity, the role of inventory tends to be emphasized, despite the impracticability of achieving complete enumeration. Documenting numbers of species (however they are delimited or defined) gives us foci for conservation advocacy and is pivotal in helping to elucidate patterns of evolution and distribution. Recognizing and naming species allow us to transfer information, but high proportions of undescribed or unrecognizable species necessitate the use of terms such as morphospecies in much ecological interpretation of diversity. Accompanying archival deposition of voucher specimens is then needed as the only reliable means through which the consistency of separations can be affirmed and crosssurvey comparisons validated. Nevertheless, other than in some temperate regions, particularly in the northern hemisphere, many estimates of insect species richness and the naming of the species present are highly incomplete. Much of the tropics, for example, harbors few resident entomologists other than those involved with pressing problems of human welfare, and more basic and sustained documentation almost inevitably depends on assistance from elsewhere. Some insects, of course, have been explored more comprehensively than others, so that selected taxonomic groups (such as butterflies, larger beetles, and dragonflies) and ecological groups ( pests ) have received more attention than many less charismatic or less economically important groups. Indeed, when collecting Psocoptera in parts of the tropics, I have occasionally been asked by local people why I am not collecting birdwing butterflies, stag beetles, or other popular (or commercially desirable!) insects, and my responses have done little to change their opinions of my insanity! In short, many gaps in knowledge of insect diversity persist, and seem unlikely to be redressed effectively in the near future, other than by guesstimates extrapolating from sometimes rather dubious foundations. However, sufficient knowledge does exist to endorse the practical need to protect natural habitats from continued despoliation and, as far as practicable, from the effects of climate change. Citations of impressively large numbers of insect species can become valuable advocacy in helping to conserve areas with largely

24 Foreword, Second Edition xxv unheralded wealth of biodiversity. The presence of unusual lineages of insects, of narrowrange endemics, and highly localized radiations and distributional idiosyncrasies (such as isolated populations beyond the main range of the taxon) are all commonplace scenarios, and may in various ways help us to designate priorities for allocating the limited conservation resources available. Many such examples from selected insect groups are revealed in this book but evaluating the richness and ecological importance of the so called meek inheritors, that vast majority of insects that do not intrude notably on human intelligence and welfare, remains a major challenge. Many such taxa receive attention from only a handful of entomologists at any time, and some are essentially orphaned for considerable periods. Progress with their documentation is inevitably slow and sporadic. Some hyperdiverse orders and families of insects exhibit daunting complexity of form and biology, as black hole groups whose elucidation is among the major challenges that face us. Insect conservation has drawn heavily on issues relevant to biodiversity and appreciation of the vast richness of insects, not only of easily recognizable species, but also of the occurrence of subspecies and other infraspecific variants, such as significant populations. This more complex dimension of insect biodiversity is receiving considerable attention as new molecular tools (such as DNA analysis) enable us to probe characters in ways undreamed of only a decade or so ago to augment the perspective provided by morphological interpretation, and assess relationships within lineages and their rates of differentiation. Applications of these tools proliferate, sometimes to the extent where small molecular differences treated in isolation may confuse, rather than clarify, relationships implied from more traditional approaches. The vast arrays of cryptic species gradually being revealed suggest that even our most up to date estimates of species numbers based on morphological data may be woefully inadequate. Insect diversity equates to variety, but the subtleties of interpopulation variations in genetic constitution and ecological performance are difficult to appraise and to categorize formally and perhaps even more difficult to communicate to non entomologists whose powers may determine the future of the systems in which those insects participate. Education and communication, based on the soundest available information, are essential components of insect conservation. This book is a significant contribution to this endeavor, through indicating how we may come to interpret and understand insect biodiversity more effectively. In addition to providing a range of opinions and facts on insect richness in a variety of taxonomic, geographical, and methodological contexts, it helps to emphasize the scientific and political importance of accurate species recognition. Failure to recognize adventive alien species may have dire economic or ecological consequences, or confusion between biotypes or cryptic species may invalidate expensive management programs for their suppression or conservation. A new generation of skilled insect systematists whose visions encompass the wider ramifications of insect biodiversity, its importance in understanding the natural world, and the accelerating impacts of humans upon it is an urgent need. They enter an exciting and challenging field of endeavor, and the perspectives included in this volume are essential background to their future contributions. The first edition of this book was a foundation and a stimulating working tool toward that end, and I expect many of the renewed chapters to become key references as we progressively refine and enlarge the bases of our understanding of insects and their activities in the modern world. Tim New Department of Ecology, Environment and Evolution La Trobe University

25 xxvii Preface, First Edition Insects are the world s most diverse group of animals, making up more than 58 percent of the known global biodiversity. They inhabit all habitat types and play major roles in the function and stability of terrestrial and aquatic ecosystems. Insects are closely associated with our lives and affect the welfare of humanity in diverse ways. At the same time, large numbers of insect species, including those not known to science, continue to become extinct or extirpated from local habitats worldwide. Our knowledge of insect biodiversity is far from complete; for example, barely 65 percent of the North American insect fauna has been described. Only a relatively few species of insects have been studied in depth. We urgently need to explore and describe insect biodiversity and to better understand the biology and ecology of insects if ecosystems are to be managed sustainably and if the effect of global environment change is to be mitigated. The scientific study of insect biodiversity is at a precarious point. Resources for the support of taxonomy are tenuous worldwide. The number of taxonomists is declining and the output of taxonomic research has slowed. Many taxonomists are reaching retirement age and will not be replaced with trained scientists, which will result in a lack of taxonomic expertise for many groups of insects. These trends contrast with an increasing need for taxonomic information and services in our society, particularly for biodiversity assessment, ecosystem management, conservation, sustainable development, management of climate change effects, and pest management. In light of these contrasting trends, the scientific community and its leadership must increase their understanding of the science of insect biodiversity and taxonomy and ensure that policy makers are informed of the importance of biodiversity for a sustainable future for humanity. We have attended and contributed to many scientific meetings and management and policy gatherings where the future, the resource needs, and importance of insect taxonomy and biodiversity have been debated. In fact, discussion of the future of taxonomy is a favorite pastime of taxonomists; there is no shortage of taxonomic opinion. Considerable discussion has focused on the daunting task of describing the diversity of insect life and how many undescribed species are out there. However, we felt that there was a need for an up to date, quantitative assessment of what insect biodiversity entails, and to connect what we know and don t know about insect biodiversity with its impact on human society. Our approach was to ask authors to develop accounts of biodiversity in certain orders of insects and geographic regions and along selected subject lines. In all categories, we were limited by the availability of willing contributors and their time and resources. Many insect groups, geographic regions, and scientific and societal issues could not be treated in a single volume. It also was apparent to us, sometimes painfully so, that many taxonomists are wildly overcommitted. This situation can be seen as part of the so called taxonomic impediment the lack of available taxonomic expertise is

26 xxviii Preface, First Edition compounded by an overburdened community of present day taxonomists with too much work and perhaps too much unrealistic enthusiasm. In Chapter 1, we introduce the ongoing challenge to document insect biodiversity and develop its services. Chapter 2 provides a comprehensive overview of the importance and value of insects to humans. The next two sections deal with regional treatments and ordinallevel accounts of insect biodiversity. These approaches were a serious challenge to the contributors who had to compile information from a wide array of sources or, alternatively, deal with situations in which accurate information simply is insufficient. In Section III, we document some of the tools and approaches to the science of taxonomy and its applications. Perspective is provided on the past, present, and future of the science of insect taxonomy and the all important influence of species concepts and their operational treatment on taxonomic science and insect biodiversity. Contributions on the increasing role of informatics and molecular approaches are provided, areas with ongoing controversy and differences of opinion. These chapters are followed by contributions on the applications of taxonomic science for which biodiversity information is fundamental, including the increasing impact of adventive insects, pest detection and management, human medical concerns, and the management and conservation of biodiversity. The book ends with an historical view of the continuing attempts to document the extent of world insect biodiversity. Robert G. Foottit Ottawa, Ontario Peter H. Adler Clemson, South Carolina

27 xxix Preface, Second Edition In the brief eight years since the publication of the first edition of Insect Biodiversity: Science and Society, there have been a number of substantial changes to entomology and the study of biodiversity. An additional 55,806 new species have been added to the global number of insect species, which now totals 1,060,704. Chapters have been updated or entirely revised to reflect advances in the understanding and knowledge of insect groups, classification, regional diversity, and a wide range of developing methodologies. We have seen the rapidly increasing influence on systematics of genomics and nextgeneration sequencing, as well as significant advances in the use of DNA barcoding in insect systematics and in the broader study of insect biodiversity, including the detection of cryptic species. Advances in information science have been significant, and the influence of the increased capability to gather, manipulate, and analyze biodiversity information is evident in many of the chapters. The compilation of this book highlighted the rapid growth of insect biodiversity and the need for an expanded treatment to address all insect groups, all zoogeographic regions of biodiversity, and the scope of systematics approaches for handling biodiversity data. The current book, thus, becomes the first in a two volume companion set of Insect Biodiversity: Science and Society. Robert G. Foottit Ottawa, Ontario Peter H. Adler Clemson, South Carolina

28 xxxi Acknowledgements We asked external reviewers to give us perspective on each chapter, and we are grateful for their efforts and appreciative of the time they took from their busy schedules. We would like to thank the following individuals who reviewed one or more chapters: P. Bouchard, C. E. Carlton, M. F. Claridge, P. S. Cranston, T. L. Erwin, C. J. Geraci, D. R. Gillespie, P. W. Hall, R. E. Harbach, J. D. Lafontaine, J. D. Lozier, P. G. Mason, H. E. L. Maw, J. C. Morse, L. A. Mound, G. R. Mullen, T. R. New, J. E. O Hara, V. H. Resh, M. D. Schwartz, G. G. E. Scudder, D. S. Simberloff, A. Smetana, A. B. T. Smith, J. Sóberon, L. Speers, F. A. H. Sperling, I. C. Stocks, M. W. Turnbull, C. D. von Dohlen, D. L. Wagner, G. Watson, A. G. Wheeler, Jr., Q. D. Wheeler, B. M. Wiegmann, D. K. Yeates, and P. Zwick. We extend our gratitude to Eric Maw for his tremendous efforts in generating the taxonomic indices for both editions. Finally, we acknowledge the encouragement and support, both moral and technical, of the past and present staff at Wiley Blackwell, particularly Laura Bell, Ward Cooper, Rosie Hayden, Kelvin Matthews, David McDade, Delia Sandford, Emma Strick land, Priya Subbrayal, Bella Talbot, and Sanjith Udayakumar, and we thank Lewis Packwood for his outstanding copyediting of the entire manuscript.