Introduction to Taxonomy of Angiosperms B.K. Verma Introduction to TAXONOMY OF ANGIOSPERMS B.K. VERMA Former Professor and Head Department of Botany University of Allahabad Allahabad New Delhi-110001 2011 INTRODUCTION TO TAXONOMY OF ANGIOSPERMS B.K. Verma © 2011 by PHI Learning Private Limited, New Delhi. All rights reserved. No part of this book may be reproduced in any form, by mimeograph or any other means, without permission in writing from the publisher. ISBN-978-81-203-4114-2 The export rights of this book are vested solely with the publisher. Published by Asoke K. Ghosh, PHI Learning Private Limited, M-97, Connaught Circus, New Delhi-110001 and Printed by Rajkamal Electric Press, Plot No. 2, Phase IV, HSIDC, Kundli-131028, Sonepat, Haryana. Contents Preface ix List of Families xi Chapter 1 INTRODUCTION 1–8 1.1 AIMS OF TAXONOMY 2 1.2 DEFINITION OF TERMS 2 1.2.1 Identification 2 1.2.2 Nomenclature 3 1.2.3 Classification 3 1.2.4 Documentation 4 1.2.5 Units of Classification and Their Concepts 4 1.3 MAJOR UNITS 4 1.3.1 Division 4 1.3.2 Class 5 1.3.3 Order 5 1.3.4 Family 5 1.4 MINOR UNITS 6 1.4.1 Genus 6 1.4.2 Species 7 1.4.3 Subspecies 8 1.4.4 Variety 8 1.4.5 Forma 8 Chapter 2 HISTORY OF PLANT CLASSIFICATION 9–18 2.1 PRE-DARWINIAN SYSTEMS 10 2.1.1 The Age of Herbals 11 2.1.2 Sexual System 12 2.1.3 Systems Based on Form Relationships 13 iii iv Contents 2.2 POST-DARWINIAN SYSTEMS 14 2.2.1 Systems Based on Phylogeny 14 2.3 TAXONOMY IN INDIA 17 2.3.1 Ancient India 17 2.3.2 16th Century Onwards 18 2.3.3 Post-Linnean Botany 18 Chapter 3 IMPORTANT SYSTEMS OF CLASSIFICATION 20–73 3.1 BENTHAM AND HOOKER’S SYSTEM 20 3.1.1 Class I: Dicotyledons 21 3.1.2 Class II: Gynospermae 24 3.1.3 Class III: Monocotyledons 25 3.1.4 Merits and Demerits of the System 25 3.2 ENGLER AND PRANTL’S SYSTEM OF CLASSIFICATION 27 3.2.1 Class I: Monocotyledoneae 28 3.2.2 Class II: Dicotyledoneae 29 3.2.3 Merits and Demerits of the System 32 3.3 HUTCHINSON’S SYSTEM OF CLASSIFICATION 33 3.3.1 Outline of Classification 35 3.3.2 Merits and Demerits of the System 42 3.4 BESSEY’S SYSTEM OF CLASSIFICATION 43 3.4.1 Phylum: Anthophyta (Angiosperms) 45 3.5 TAKHTAJAN’S SYSTEM OF CLASSIFICATION 49 3.5.1 Division—Magnoliophyta (Angiospermae) 51 3.5.2 Merits and Demerits of Takhtajan’s System of Classification 58 3.6 CRONQUIST’S SYSTEM OF CLASSIFICATION 59 3.6.1 Division: Magnoliophyta (Angiosperms) 60 3.6.2 Differences between Systems of 1968 and 1981 66 3.6.3 Merits and Demerits of Cronquist’s System of Classification 66 3.7 WETTSTEIN’S SYSTEM OF CLASSIFICATION 68 3.7.1 Class I: Dicotyledons 68 3.7.2 Class II: Monocotyledons 71 3.7.3 Merits and Demerits of Wettstein’s System of Classification 72 Chapter 4 PLANT NOMENCLATURE 74–82 4.1 FIRST CODE OF NOMENCLATURE ‘THE PARIS CODE’, 1867 75 4.2 IMPORTANT AND MAJOR RULES OF NOMENCLATURE 75 4.2.1 Rank of Taxa 75 4.2.2 Typification (Articles 7–10) 76 4.3 PRINCIPLES OF PRIORITY (Articles 11–15) 78 4.4 EFFECTIVE AND VALID PUBLICATIONS (Articles 29–45) 78 4.5 AUTHOR CITATION (Articles 46–50) 79 Contents v 4.6 RETENTION AND CHOICE OF NAMES 80 4.7 REJECTION OF NAMES 80 4.8 SOME IMPORTANT DATES IN BOTANICAL NOMENCLATURE 81 Chapter 5 CURRENT TRENDS IN PLANT TAXONOMY 83–121 5.1 ANATOMY AND TAXONOMY 83 5.1.1 Anatomical Characters 83 5.2 EMBRYOLOGY AND TAXONOMY 91 5.2.1 Use of Embryological Characters Among Major Taxa 93 5.2.2 At Family Level 94 5.2.3 At Generic Level 98 5.3 PALYNOLOGY AND TAXONOMY 99 5.3.1 Taxonomic Characters of Pollen Grains 99 5.3.2 Use of Pollen Character in Plant Taxonomy 102 5.4 CHEMISTRY AND TAXONOMY 104 5.4.1 Directly Visible Characters 105 5.4.2 Plant Products 106 5.4.3 Serum Analysis or Serology 109 5.4.4 Biosynthetic Pathways 109 5.4.5 DNA Hybridization 110 5.5 CYTOLOGY AND TAXONOMY 111 5.5.1 Chromosome Number 111 5.5.2 Chromosome Morphology 113 5.5.3 Chromosome Behaviour at Meiosis and in Crosses 114 5.5.4 Heterochromatin 114 5.5.5 Use of Cytological Data at Family Level 115 5.5.6 Use of Cytological Data at Genus Level and Below 117 5.6 ECOLOGY AND TAXONOMY 117 5.6.1 Phenotypic Plasticity 118 5.6.2 Ecological Factors and Genotype 119 5.6.3 Genotype and Physical Environment 119 5.6.4 Genotype and the Biotic Environment 120 5.6.5 Ecotypic Variations 120 Chapter 6 SELECTED FAMILIES OF ANGIOSPERMS: DICOTYLEDONS 122–338 6.1 POLYPETALAE (Thalmiflorae) 122 6.1.1 Order—Ranales 122 6.1.2 Order—Parietales 145 6.1.3 Order—Caryophyllineae 167 6.1.4 Order—Guttiferales 172 6.1.5 Order—Malvales 176 vi Contents 6.2 POLYPETALAE (Disciflorae) 186 6.2.1 Order—Geraniales 186 6.2.2 Order—Celastrales 194 6.2.3 Order—Sapindales 197 6.3 POLYPETALAE (Calyciflorae) 201 6.3.1 Order—Rosales 201 6.3.2 Order—Myrtales 217 6.3.3 Order—Passiflorales 221 6.3.4 Order—Umbellales 229 6.4 SUB-CLASS—GAMOPETALAE 234 6.4.1 Order—Rubiales 234 6.4.2 Order—Asterales 240 6.4.3 Order—Primulales 252 6.4.4 Order—Gentianales 255 6.4.5 Order—Polemoniales 265 6.4.6 Order—Personales 282 6.4.7 Order—Lamiales 298 6.5 MONOCHLAMYDEAE 309 6.5.1 Series—Curvembryae 309 6.5.2 Series—Unisexuales 321 Chapter 7 SELECTED FAMILIES OF ANGIOSPERMS: MONOCOTYLEDONS 339–390 7.1 MONOCOTYLEDONEAE (Ovary Inferior) 339 7.1.1 Series—Microspermae 339 7.1.2 Series—Epigynae 345 7.2 MONOCOTYLEDONEAE (Ovary Superior) 362 7.2.1 Series—Coronarieae 362 7.2.2 Series—Calycinae 367 7.2.3 Series—Nudiflorae 372 7.2.4 Series—Glumaceae 376 Chapter 8 ORIGIN OF ANGIOSPERMS 391–405 8.1 THE ANTIQUITY (TIME) OF ORIGIN OF ANGIOSPERMS 391 8.1.1 Lower Cretaceous Angiosperms 394 8.2 THE CRADLE (PLACE) OF THE ANGIOSPERMS 396 8.2.1 Greenland as the Cradle of Angiosperms 396 8.2.2 Tropical Region as the Site of Origin 396 8.2.3 Pacific Islands as the Cradle of Angiosperms 396 8.2.4 South Africa as the Cradle of Angiosperms 396 8.3 THE ANCESTORS OF ANGIOSPERMS 397 8.3.1 Bennettitalean Theory 397 8.3.2 Caytonialean Theory 398 Contents vii 8.3.3 Pteridosperm Theory 400 8.3.4 Pentoxylales Theory 400 8.3.5 Dirhopalostachyacean Theory 401 8.3.6 Czekanowskialean Theory 401 8.3.7 Gonophyll Theory 402 8.3.8 Coniferales—Amentiferae Theory 402 8.3.9 Ephedrales Theory 402 8.3.10 Gnetales—Angiosperm Theory 403 8.3.11 Durian Theory 403 8.3.12 Gigantopteridalean Theory 404 Chapter 9 FIELD AND HERBARIUM TECHNIQUES 406–413 9.1 PURPOSES OF MODERN HERBARIUM 406 9.2 DIFFERENT TYPES OF HERBARIA 407 9.2.1 National or Major Herbaria 407 9.2.2 Regional Herbaria 407 9.2.3 Local Herbaria 407 9.3 IMPORTANCE OF HERBARIA IN BOTANICAL RESEARCH 407 9.3.1 Anatomy 407 9.3.2 Palynology 408 9.3.3 Physiology, Biochemistry and Chemotaxonomy 408 9.3.4 Biosytematics 408 9.4 HERBARIUM TECHNIQUES 409 9.4.1 Collection 409 9.4.2 Pressing 410 9.4.3 Drying 410 9.4.4 Poisoning 410 9.4.5 Mounting 411 9.4.6 Labelling 411 9.4.7 Storage and Arrangement of Herbarium Sheets in a Herbarium 411 9.4.8 Fumigation 412 Appendix I Key to Families Described in the Book 415–418 Appendix II Pro Forma for the Description of a Flowering Plant 419–422 Appendix III Synopsis of Families and Suprafamilial Taxa of Magnoliophyta 423–436 Glossary 437–446 References 447–469 Index of Botanical Names 471–489 Index 491–492 Preface I wrote a book under the title Introduction to Taxonomy of Flowering Plants in 1976, wherein thirty-three families and three well known systems of classification were covered. It was reprinted in 1982. Due to several unavoidable circumstances, it was not possible to bring out further editions and that title had to be abondoned. In the present book, I have included fifty families and seven systems of classification and have tried to cover the syllabi of most of the Indian universities. The book has been written basically to cater to the needs of undergraduate students, but there are chapters like plant nomenclature, current trends in plant taxonomy, origin of angiosperms, etc. which may be of great use to postgraduate students and also to candidates studying for various competitive examinations. The families have been arranged according to the Bentham and Hooker’s system of classification. The number of genera and species at world level is based on Willis—Dictionary of Flowering Plants and Ferns, 8th edition, and that of India, on Flora of India—Introductory volume, published by Botanical Survey of India (BSI). In each family, information about endemic taxa is given after its general account, and one or two plants have been described for the benefit of students for their practical work.