A Textbook of Agricultural Entomology David V Alford BSc PhD Formerly Senior Advisory Entomologist and Head of the Entomology Department, ADAS, Ministry of Agriculture, Fisheries and Food, Cambridge, UK b Blackwell Science ©1999 Blackwell Science Ltd Editorial Offices: Osney Mead, Oxford OX2 OEL 25 John Street, London WC1N 2BL 23 Ainslie Place, Edinburgh EH3 6AJ 350 Main Street, Maiden MA 02148 5018, USA 54 University Street, Carlton Victoria 3053, Australia 10, rue Casimir Delavigne 75006 Paris, France Other Editorial Offices: Blackwell Wissenschafts-Verlag GmbH Kurfiirstendamm 57 10707 Berlin, Germany Blackwell Science KK MG Kodenmacho Building 7-10 Kodenmacho Nihombashi Chuo-ku, Tokyo 104, Japan The right of the Author to be identified as the Author of this Work has been asserted in accordance with the Copyright, Designs and Patents Act 1988 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 the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher First published 1999 Set in 10 on 12pt Times by Best-set Typesetter Ltd., Hong Kong Printed and bound in Great Britain by MPG Books Ltd, Bodmin, Cornwall The Blackwell Science logo is a trade mark of Blackwell Science Ltd, registered at the United Kingdom Trade Marks Registry DISTRIBUTORS Marston Book Services Ltd PO Box 269 Abingdon Oxon OX14 4YN (Orders: Tel: 01235 465500 Fax: 01235 465555) USA Blackwell Science, Inc Commerce Place 350 Main Street Maiden, MA 02148 5018 (Orders: Tel: 800 759 6102 781 388 8250 Fax: 781 388 8255) Canada Login Brothers Book Company 324 Saulteaux Crescent Winnipeg, Manitoba R3J 3T2 (Orders: Tel: 204 837-2987 Fax: 204 837-3116) Australia Blackwell Science Pty Ltd 54 University Street Carlton, Victoria 3053 (Orders: Tel: 03 9347 0300 Fax: 03 9347 5001) A catalogue record for this title is available from the British Library ISBN 0-632-05297-X Library of Congress Cataloging-in-Publication Data Alford, D V A textbook of agricultural entomology/David V Alford p cm Includes bibliographical references ISBN 0-632-05297-X (pbk.) Insect pests Beneficial insects Plant mites Agricultural pests I Title SB931.A474 1999 632'.7—dc21 99-34207 CIP For further information on Blackwell Science, visit our website: www.blackwell-science.com Contents Preface v Part I The Main Groups of Insects and Mites Insects External features Internal features Development and growth Classification of the class Insecta Order COLLEMBOLA (springtails) Order SALTATORIA (crickets, grasshoppers, etc.) Order DERMAPTERA (earwigs) Order DICTYOPTERA (cockroaches and mantids) Order PSOCOPTERA (psocids) Order PHTHIRAPTERA (lice) Order HEMIPTERA (true bugs) Order THYSANOPTERA (thrips) Order NEUROPTERA (lacewings, etc.) Order COLEOPTERA (beetles) Order DIPTERA (true flies) Order LEPIDOPTERA (butterflies and moths) Order TRICHOPTERA (caddis flies) Order HYMENOPTERA (ants, bees, sawflies, wasps, etc.) 3 13 14 15 16 17 17 18 19 29 30 33 42 52 65 66 Mites External features Internal features Development and growth Classification of the subclass Acari Order MESOSTIGMATA Order IXODIDA (ticks) Order PROSTIGMATA Order ASTIGMATA Order CRYPTOSTIGMATA (beetle mites) 75 75 76 77 77 77 79 79 83 84 IV Contents Part II Pests of Agricultural and Horticultural Crops 85 Small Insect Orders Order COLLEMBOLA (springtails) Order DERMAPTERA (earwigs) Order THYSANOPTERA (thrips) Order TRICHOPTERA (caddis flies) 87 87 89 89 94 Main Insect Orders Order HEMIPTERA (true bugs) Order COLEOPTERA (beetles) Order DIPTERA (true flies) Order LEPIDOPTERA (butterflies and moths) Order HYMENOPTERA (ants, bees, sawflies, wasps, etc.) 96 96 126 163 202 245 Mites Order PROSTIGMATA Order ASTIGMATA Order CRYPTOSTIGMATA (beetle mites) 255 255 269 270 Cultivated Host Plants Cited in the Text Under Their Common Name Wild Host Plants Cited in the Text Under Their Scientific Name Glossary Selected Bibliography 271 275 277 285 Host Plant Index General Index 288 292 Preface This book offers students of applied entomology and zoology an introduction to the insects and mites of agricultural or horticultural importance in the British Isles and in other parts of northwestern Europe In Part I, insects and mites are described in general terms, usually down to family level The primary intention is to provide background information on the features of the main groups of pests and beneficial species (e.g parasites, parasitoids and predators), largely using descriptive characters capable of appreciation without undue experience or the need for specialist equipment other than a hand lens or a low-power microscope In Part II, emphasis is placed on pests of field, glasshouse, orchard and plantation crops Owing to limitations of space, cursory mention only is made of the vast range of pests found on ornamental plants and forest trees; however, pests of several minor crops that may on occasions require the attention of crop protectionists and practitioners are included, especially where published information on them is limited or not readily available Within the various orders, individual families are treated in the same systematic sequence as described in Part I; however, within each family (for ease of reference) the various genera are considered alphabetically, without regard to their systematic hierarchy Within genera, the main pest species are described and details provided of their biology, host range and economic importance; where appropriate, these entries are followed by additional entries or notes on other species For clarity of presentation, synonyms for names of the pests are excluded from the text However, frequently used alternative names (not all of which are strictly synonyms) are cross-referenced in the general index; this should enable readers to trace pests known to them, or cited in other literature, under different names Names of authorities for species are given in full but abbreviated (as shown) for Fabricius (F.) and Linnaeus (L.) Within the text, plants are referred to under their common name if a crop or under their scientific name if a wild host; the scientific names of crops and the common names of wild plants are listed on pages 271 et seq and 275 et seq., respectively Details of pest control measures are deliberately excluded from the text, as these all too rapidly become outdated; also, general statements on pest control measures were not thought to be of great value in a book such as this Readers requiring information on pest control or pest management should consult more specific (ideally, regularly revised) books, booklets or leaflets produced by agrochemical companies, extension services and other bodies - examples of publications dealing with pest control on UK crops include: the Pest and Disease Management Handbook (published by Blackwell Science and BCPC); and The UK Pesticide Guide (published annually by CAB International and BCPC) Matters such as pest population growth and development have also been excluded from the present book, as these were considered more appropriate for discussion within a publication dealing with the principles of pest management VI Preface In compiling this account of crop pests, I am indebted to numerous friends and colleagues, either for their help in obtaining material or for their guidance on specific issues Particular thanks are offered to my wife and to D.J Carter, B.J Emmett, A.W Jackson, M.J Lole, D MacFarlane, Mrs H.M Maher, Dr W Powell, H Riedel, Dr G Rimpel, P.R Seymour, S.J Tones, R.A Umpelby and J.E.B Young Most of the illustrations have been based on specimens in my own collection Other invaluable sources of material included the insect collections formerly housed in the now disbanded ADAS Entomology Departments at Bristol, Cambridge and Starcross - regrettably, these reference collections (all of which included important material dating back to the 1920s and beyond) no longer exist Finally, I am indebted to Professor T Lewis CBE for his critical appraisal of the final manuscript and suggestions for its improvement David V Alford Cambridge May 1999 PART I The Main Groups of Insects and Mites Insects Insects form a major class of organisms within the phylum Arthropoda All arthropods have segmented bodies, with a hard exoskeleton or body shell and jointed limbs, but insects (class Insecta) are typified by the presence of three pairs of true legs, usually two pairs of wings and a body divided into three distinct regions: head, thorax and abdomen (Fig 1) (cf Acari, p 75) EXTERNAL FEATURES The often tube-like body of an insect is composed of a series of segments: six in the head, three in the thorax and up to 11 in the abdomen Each segment is formed from up to four more or less horny plates called sclerites - a dorsal tergum, a ventral sternum and two lateral pleura (pleura are absent from the insect abdomen) These plates and the various adjacent body segments may be fused together rigidly or joined by soft, flexible membranes that allow for body movement The body appendages, such as the legs, are formed as outgrowths from the pleura Where fusion has occurred (particularly in the head) the segments, or their individual components, are not always distinguishable; in the thorax, the sclerites are themselves often subdivided into smaller plates The body of an insect is covered by a protective three-layered skin (cuticle) formed from chitin and protein Depending upon its precise composition and thickness, the cuticle may be soft and flexible or hard and rigid; according to requirements, it may or may not be permeable or waterproof Following its deposition, the cuticle becomes more or less hardened and darkened by the addition of melanin, during a process called sclerotization Pre-adult (immature) insects usually moult from one growth stage to the next, sloughing off or bursting out of the 'old' cuticle and replacing it with a larger one; each moult is called an ecdysis Except in certain very primitive forms, the cuticle of an adult insect is not replaceable External features of the cuticle (e.g details of punctation and sculpturing in adult beetles) are often characteristic of the species Further, the insect body is often adorned with bristles, hairs, scales, setae or spines, and these cuticular outgrowths are also of considerable help in identifying groups or individual species Immediately beneath the cuticle lies an almost continuous single layer of cells (the epidermis); it is the epidermis that secretes the cuticle Some epidermal cells are differentiated into glands that may secrete compounds to the outside via ducts that end in characteristic cuticular pores Glandular secretions include pheromones, silk, wax and other products The insect head is essentially a capsule which encloses the brain and bears the usually external (ectognathous) mouthparts, the eyes and a pair of sensory antennae The mouthparts comprise five basic sections: an 'upper lip' (labrum), the Plate la Earwig (Forficula auricularia) damage to celery Plate lb Earwig (Forficula auricularia) damage to a cob of sweet corn Plate lc Western flower thrips (Frankliniella occidentalis) damage to a cucumber leaf Plate Id Western flower thrips (Frankliniella occidentalis) damage to a cucumber flower Plate le Glasshouse leafhopper (Hauptidia maroccana) damage to a tomato leaf Plate If Cabbage whitefly (Aleyrodes proletella) on a cabbage leaf Plate 4b Fmal-instar larva of Oulema lichenis Plate 4a Adult of Oulema lichenis Plate 4c Final-instar larva of cereal leaf beetle Oulema melanopa) Plate 4d Eggs of watercress beetle (Phaedon cochleariae) on a watercress leaf Plate 4f Cabbage stem flea beetle (Psylliodes chrysocephala) damage to winter oilseed rape Plate 4e Larvae of watercress beetle {Phaedon •ochleariae) on a watercress leaf Plate 3a Cereal ground beetle (Zabnis tenebrioides) damage to winter barley Plate 3c Larva of cereal ground beetle (Zabnis tenebrioides) Plate 3b Cereal ground beetle (Zabnis tenebrioides) Plate 3d Larva of garden chafer (Phyllopertha hordeola) Plate 3f Colorado beetle (Leptinotarsa decemlineata) Plate 3e Dead central shoot on a wheat plant attacked by wheat flea beetle (Crepidodera Plate 6a Sand weevil (Philopedon plagiatus) Plate 6c Larvae of brassica pod midge {Dasineura brassicae) Plate 6b Larva of common leaf weevil (Phyllobius pyri) Plate 6d Puparia of hessian fly (Mayetiola destructor) Plate 6e Mushroom scuttle fly (Megaselia nigra) damage to mushroom m^Bk Plate 6f Large narcissus fly (Merodon equestris) Plate 5a Cabbage seed weevil (Ceutorhynchus assimilis) larval exit hole in a pod wall Plate 5b Larva of rape stem weevil (Ceutorhynchus napi) Plate 5c Cabbage stem weevil (Ceutorhynchus pallidactylus) Plate 5d Rape winter stem weevil (Ceutorhynchus picitarsis) damage to winter oilseed rape Plate 5e Gall of a turnip gall weevil (Ceutorhynchus pleurostigma) on the roots of turnip Plate 5f Section through the gall of a turnip gall weevil (Ceutorhynchus pleurostigma) Plate 8a Leaf mine of Scaptomyza flava on winter oilseed rape Plate 8c Leaf mine of Cerodontha incisa on sweet corn Plate 8b Puparium of Scaptomyza flava in a leaf of winter oilseed rape Plate 8d Larva of Phytomyza rufipes Plate 8f Gout fly (Chlorops pumilionis) Plate 8e Leaf mines of Phytomyza horticola on pea Plate 7a Leaf mine of celery fly (Euleia heraciei) on celery Plate 7b Larva of carrot fly (Psila rosae) Plate 7c Larva of grass & cereal fly (Geomyza tripunctata) Plate 7d Puparfum of grass & cereal fly (Geomyza tripunctata) Plate 7e Wheat shoot infested by a larva of yellow cereal fly (Opomyza florum), showing a characteris tic spiral mark at the base Plate 7f Larva of yellow cereal fly (Opomyza florum) Plate 10b Beet leaf miners (Pegomya hyoscyami) Plate 10a Larval mines of cabbage root fly (Delia radicum) in the tap root of radish Plate 10c Female ghost swift moth (Hepialus humuli) Plate lOd Larva of ghost swift moth (Hepialus humuli) Plate lOe Larva of garden swift moth (Hepialus lupulinus) Plate lOf Larva of leopard moth (Zeuzera pyrina) Plate 9a Larva of gout fly (Chlorops pumilionis) Plate 9b Puparium of gout fly (Chlorops pumilionis) Plate 9e Wheat bulb fly (Delia coarctata) Plate 9f Larva of wheat bulb fly (Delia coarctata) Plate 12a Male fruit tree tortrix moth (Archips podana) Plate 12b Larva of fruit tree tortrix moth {Archips podana) Plate 12c Larva and larval habitation of flax tortrix moth (Cnephasia asseclana) Plate 12d Omnivorous leaf tier (Cnephasia longana) Plate 12e Larva of pea moth (Cydia nigricana) Plate 12f Pea moth (Cydia nigricana) Plate 11a Pupa and pupal cocoon of leek moth (Acrolepiopsis assectella) Plate l i b Leek moth (Acrolepiopsis assectella) Plate l i e Larva and larval web of Epermenia chaerophyllella on parsnip Plate l i d Adult of Epermenia chaerophyllella Plate l i e Parsnip moth (Depressaria pastinacella) Plate l l f Larva of parsnip moth (Depressaria pastinacella) Plate 14a Larva of Pyrausta aurata Plate 14b Larvae of large white butterfly (Pieris brassicae) Plate 14c Larva of small white butterfly {Pieris rapae) Plate 14d Larva of brown-tail moth (Euproctis chrysorrhoea) Plate 14e Larva of turnip moth (Agrotis segetum) damaging a potato tuber Plate 14f Shark moth (Cucullia umbratica) Plate 13a Garden grass veneer moth {Chrysoteiichia culmella) Plate 13b Larva of garden grass veneer moth (Chrysoteiichia culmella) Plate 13d Larva of a garden pebble moth (Evergestis forficalis) Plate 13e European corn borer (Ostrinia nubilalis) Plate 13f Adult of Pyrausta aurata Plate 15a Larva of bordered straw moth (Heliothis peltigera) Plate 15b Larva of rosy rustic moth {Hydraecia micacea) boring within a wheat stem Plate 15c Larva of tomato moth (Lacanobia oleracea) Plate 15d Eggs and first-instar larvae of cabbage moth {Mamestra brassicae) and typical 'windowing' damage on a cabbage leaf Plate 15e Larva of common rustic moth (Mesapamea secalis) Plate 15f Mediterranean brocade moth {Spodoptera littoralis) ... of glands (labial glands, mandibular glands, maxillary glands and thoracic glands) are also asso- ciated with the mouthparts The basic biting mouthparts of an insect may be modified considerably.. .A Textbook of Agricultural Entomology David V Alford BSc PhD Formerly Senior Advisory Entomologist and Head of the Entomology Department, ADAS, Ministry of Agriculture, Fisheries and Food, Cambridge,... Hindleg of a leafhopper - family Cicadellidae Fig 32 Hindleg of a leafhopper - family Delphacidae 1A and 2A of forewings Y-shaped, being united distally (Fig 30b) EXAMPLE: Javesella pellucida