Floral Diagrams: An Aid to Understanding Flower Morphology and Evolution Book

Foreword xi

Preface xiii

Acknowledgments xv

Part I Introduction to floral diagrams 1

1 Introduction to flower morphology 3

1.1 Definition of flowers 3

1.2 Floral organs 5

1.2.1 Perianth 5

1.2.2 Androecium 8

1.2.3 Gynoecium 14

1.3 The floral axis and receptacle 18

1.4 Floral nectaries 21

1.5 Relationship of flowers with inflorescences 22

1.5.1 Terminal and lateral flowers 22

1.5.2 Pseudanthia 23

1.5.3 Bracts and bracteoles 24

1.5.4 Epicalyx and calyculus 24

1.6 Symmetry and orientation of flowers 25

1.7 Phyllotaxis 28

1.7.1 Whorls and spirals 28

1.7.2 Merism 30

1.7.3 Aestivation patterns 32

1.8 Fusion of floral parts 33

1.8.1 Congenital and postgenital fusion 33

1.8.2 Sympetaly and common stamen-petal tubes 34

2 Floral diagrams 36

2.1 Definition and significance of floral diagrams 36

2.2 Types of floral diagrams 37

2.3 Floral diagrams and floral formulae 38

2.4 Problems of three-dimensional complexity 39

2.5 Representation of accessory structures 41

2.6 Floral heteromorphism and unisexual flowers 43

2.7 Floral development and floral diagrams 44

2.8 Evolutionary developmental genetics and floral diagrams 48

3 Floral diagrams used in this book 51

Part II Floral diagrams in the major clades 55

4 Systematic significance of floral diagrams 57

4.1 Floral diagrams and molecular phylogeny 57

4.1.1 Molecular and morphological characters 57

4.1.2 The Angiosperm Phylogeny Group classification 59

4.1.3 Fossil flowers and floral diagrams 61

4.2 Overview of floral diagrams in the major clades of flowering plants 62

5 Basal angiosperms: the ascent of flowers 63

5.1 The ANA-grade: Amborellales, Austrobaileyales, Nymphaeales 63

5.2 Magnoliales 70

5.3 Laurales 75

5.4 Piperales 82

6 Monocots: variation on a trimerous Bauplan 88

6.1 The basal monocots: Acorales and Alismatales 88

6.2 The lilioids: Asparagales, Dioscoreales, Pandanales, Liliales 98

6.3 The commelinids: Arecales, Commelinales, Poales, Zingiberales 112

7 Early diverging eudicots: a transition between two worlds 129

7.1 Ranunculales 129

7.2 The basal eudicot grade: Sabiales, Proteales, Trochodendrales, Buxales 140

8 Basal core eudicots: the event of pentamerous flowers 149

8.1 Gunnerales and Berberidopsidales 149

8.2 Santalales 154

8.3 Dilleniales 159

9 Caryophyllids: how to reinvent lost petals 163

9.1 Polygonales 164

9.2 Core Caryophyllales 175

10 Rosids: the diplostemonous alliance 193

10.1 Saxifragales 193

10.2 Malvids 203

10.2.1 Early diverging malvids: Geraniales, Myrtales 203

10.2.2 Remaining malvids: Malvales, Brassicales, Sapindales 217

10.3 Fabids 243

10.3.1 COM-clade: Celastrales-Oxalidales-Malpighiales 244

10.3.2 Remaining fabids: Cucurbitales, Fabales, Fagales, Rosales 269

11 Asterids: tubes and pseudanthia 292

11.1 Basal asterids: Cornales, Ericales 292

11.2 Lamiids: Solanales, Gentianales, Lamiales 314

11.3 Campanulids: Dipsacales, Apiales, Asterales 333

Part III Conclusions 349

12 Distinctive systematic characters and cryptic apomorphies 351

13 Floral diagrams and major angiosperm groups 353

13.1 Basal angiosperms, monocots and early diverging eudicots 353

13.2 Core eudicots 357

14 Outlook 364

References 365

Glossary 403

Taxonomic index 414

Subject index 430