CHARACTER VARIATION AND A CLADISTIC ANALYSIS OF THE GENUS Lachenalia Jacq:f. ex Murray (Hyacinthaceae:Massonieae) by GRAHAM D. DUNCAN Submitted in fulfilment ofthe academic requirements for the degree of Master of Science in the Discipline ofBotany, School ofBotany and Zoology University ofKwaZulu-Natal Pietermaritzburg 2005 11 Lachenalia bulbifera (Cirillo) Engl. from Pierre-Joseph Redoute's Les Liliacees, Volume 1, Plate 52 (1802). 11l ABSTRACT Morphological variation and a cladistic analysis ofthe large, endemic southemAfrican genus Lachenalia Jacqj ex Murray (Hyacinthaceae: Massonieae) is presented. Its close taxonomic relationship with the small endemic sympatric genus Polyxena Kunth (which has been included in the morphological and cladistic study) is discussed. The inclusion ofPolyxena within Lachenalia is supported. One hundred and twenty species (139 taxa), comprising 115 Lachenalia and five Polyxena species are recognised. A wide range of morphological characters were analysed, including macromorphology, micromorphology, anatomy and palynology. A discussion and comparison of karyological data is also presented. A brief historical background, speCIes diversity maps, figures, tables, appendices and illustrations of anatomical, micromorphological and macromorphological characters, and cladistic data, are presented, as well as discussions ofpollination biology and phytogeography. This work is based on species studied in their natural habitats as well as under cultivation, and from representative herbarium specimens examined from BOL, NBG, PRE and SAM. IV PREFACE The experimental work described in this dissertation was carried out in the School ofBotany and Zoology, University ofKwaZulu-Natal, Pietermaritzburg, and at Kirstenbosch National Botanical Garden, Cape Town, from January 1998 to November 2004, under the supervision ofProfessor Trevor Edwards. These studies represent original work by the author and have not otherwise been submitted in any form for any degree or diploma to any University. Where use has been made ofthe work of others it is duly acknowledged in the text. Signed: Graham D. Duncan (candidate). Signed: Professor Trevor 1. Edwards (supervisor). v CONTENTS 1 INTRODUCTION 1 2 HISTORICAL SyNOPSIS 4 2.1 THE PRE-LINNEAN PERIOD .4 2.2 THE POST-LINNEAN PERIOD 4 2.3 THE CONTRIBUTION OF lG. BAKER 5 2.4 THE CONTRIBUTION OF W.E BARKER 6 2.5 RECENT DEVELOPMENTS 7 3 MATERIALS AND METHODS 9 4 GENERIC DELIMITATION 10 5 MORPHOLOGy 19 5.1 MATERIALS AND METHODS 19 5.2 HABIT 20 5.2.1 Results 23 5.3 ROOTS 24 5.3.1 Results 24 5.4 BULB 25 5.4.1 Results 26 5.5 CATAPHYLLS 33 5.5.1 Results 33 5.6 LEAVES 35 5.6.1 Results 36 5.7 SEED GERMINATION, JUVENILE LEAF MORPHOLOGY AND ONTOGENy 60 5.7.1 Materials and methods 61 VI 5.7.2 Results 61 5.8 LEAF ANATOMY AND MICROMORPHOLOGy 68 5.8.1 Materials and methods 69 5.8.2 Results 70 5.8.2.1 Epidermis 70 5.8.2.2 Mesophyll 81 5.8.2.3 Margins 84 5.9 INFLORESCENCE 90 5.9.1 Results 90 5.1 0 PEDUNCLE 99 5.10.1 Results 99 5.11 RACHIS 101 5.11.1 Results 101 5.12 BRACTS 103 5.12.1 Results 103 5.13 PERIANTH 106 5.13.1 Results 106 5.14 FLOWER PIGMENTS 131 5.14.1 Materials and methods 132 5.14.2 Results 132 5.14.2.1 Plastid pigments 132 5.14.2.2 Anthocyanin pigments 133 5.15 STAMENS 133 5.15.1 Results 133 Vll 5.16 POLLEN 150 5.16.1 Materials and methods 150 5.16.2 Results 150 5.17 GYNOECIUM 153 5.1 7.1 Materials and methods ·······.153 5.17.2 Results 154 5.17.2.1 Style and Stigma 154 5.17.2.2 Ovary 159 5.18 FRUIT 161 5.18.1 Results 161 5.19 SEED 168 5.19.1 Materials and methods 169 5.19.2 Results 169 5.20 KARyOLOGy 199 6INFRAGENERIC CLASSIFICATION 207 6.1 SPECIES CONCEPTS 207 6.2 PHENOTYPIC AND GENOTYPIC VARIATION 208 6.3 DESIGNATION OF RANKS 211 6.3.1 Species, subspecies and varietal rank 211 7 PHENOLOGy 213 7.1 FLOWERING AND LEAFING PERIOD 213 8 POLLINATION BIOLOGy 219 8.1 MELLITOPHILY 220 8.2 ORNITHOPHILY 221 8.3 RODENT POLLINATION 222 Vlll 9 PHYTOGEOGRAPHy 223 9.1 MATERIALS AND METHODS 223 9.2 DISTRIBUTION 225 9.3 FACTORS PROMOTING SPECIATION AND DISTRIBUTION .226 10 PHYLOGENY 230 10.1 MATERIALS AND METHODS .230 10.1.1 Characters 230 10.1.2 C1adogram construction 231 10.2 RESULTS AND DISCUSSION 232 10.2.1 Analysis 1 232 10.2.2 Analysis 2 238 10.2.3 Homoplasy 243 10.2.3.1 Vegetative homoplasy 246 10.2.3.2 Reproductive homoplasy 259 10.3 CONCLUSIONS , 276 LIST OF FIGURES, TABLES AND APPENDICES 278 REFERENCES 288 APPENDICES 306 IX ACKNOWLEDGEMENTS I extend my grateful thanks to the following persons and institutions: My supervisor, Professor Trevor Edwards, for his expert guidance, constructive criticism, patience and encouragement, and for preparing the line drawings in Figure 30. Professor Esme Hennessy, member ofmy research committee, for her advice and encouragement. Dr Andrew Mitchell, formerly senior lecturer, School ofMolecular and Cellular Biosciences at the Unversity ofKwaZulu-Natal, Pietermaritzburg, for his expert technical assistance with the c1adistic analyses. The staff ofthe Centre for Electron Microscopy at the University ofKwaZulu-Natal, Pietermaritzburg, for their assistance, especially Mr Veejay Bandu, Mrs Belinda White and Mrs Priscilla Donnelly. Ms Olwen Grace, for assistance with image scanning. Dr John Manning, scientific leader, Compton Herbarium, for advice on anatomy, seed morphology and c1adistics. Dr Gail Reeves, Head ofthe Leslie Hill DNA Laboratory, Kirstenbosch Research Centre, for assistance with the c1adistic analyses. Dr Koos Roux, collections manager, and Ms Pascale Chesselet, agricultural scientist, both ofthe Compton Herbarium, for assistance with box and whisker graphs and the phenology table, respectively. Dr Deirdre Snijman, principal scientist, Compton Herbarium, for advice on c1adistics. Ms Ferozah Conrad and Dr Felix Forest, Kirstenbosch Research Centre, for technical support with the c1adistic analyses. Ms Alice Notten, horticultural colleague at Kirstenbosch Botanic Garden, for her tireless assistance with page setups. Dr Louis Vogelpoel, for advice on flower pigments. Dr Peter Bruyns, for advice on phytogeography. Mr Robert Scott, for generously providing accommodation during numerous visits to Pietermaritzburg. Prof. Brian Huntley, ChiefDirector ofthe South African National Biodiversity Institute, and Mr Philip le Roux, Curator ofKirstenbosch Botanical Garden, for allowing me to undertake this study. Friends, colleagues and family for their support. x UNPUBLISHED NAME CHANGES IN THIS THESIS (a) Combinations awaiting publication used throughout the thesis for expedience. Lachenalia glauca (W.F.Barker) G.D.Duncan Lachenalia trichophylla Baker subsp. massonii (Baker) G.D.Duncan (b) Taxa awaiting publication used throughout the thesis for expedience. Lachenalia aloides (Lf) Engl. var. bonaspei G.D.Duncan Lachenalia aloides (Lf) Engl. var. piketbergensis W.F.Barker ex G.D.Duncan Lachenalia aloides (Lf) Engl. var. thunbergii W.F.Barker ex G.D.Duncan Lachenalia arida G.D.Duncan Lachenalia canaliculata G.D.Duncan Lachenalia contaminata Aiton var. exserta G.D.Duncan Lachenalia cernua G.D.Duncan Lachenaliafasciculata G.D.Duncan Lachenalia komsbergensis G.D.Duncan Lachenalia lutea G.D.Duncan Lachenalia nardouwensis G.D.Duncan Lachenalia undulata Masson ex Baker subsp. grandifolia G.D.Duncan Lachenalia urceolata G.D.Duncan Lachenalia wiesei G.D.Duncan 1 1 INTRODUCTION The horticulturally important, and botanically diverse genus Lachenalia lacqf ex Murray is endemic to southern Africa, and comprises 115 species in the family Hyacinthaceae. The genus was described by l.A. Murray in 1784, with 1. tricolor lacqf (now 1. aloides (Lf) Engl.)) as the type species. Lachenalia is morphologically and cytologically variable. Polyxena is a paraphyletic genus (Pfosser & Speta 1999, Pfosser et al. 2003, van der Merwe 2002, Manning et at. 2004) which was established by Kunth in 1843. The distribution of Lachenalia extends from the western and southern parts of Namibia southwards into South Africa, where it occurs in the Richtersve1d, western Bushmanland, throughout Namaqualand, the northwestern, western, southwestern and southern parts of the Western Cape, the Great and Little Karoo, and the western, southern, south-eastern and northeastern parts ofthe Eastern Cape (Duncan 1988a). Its distribution extends as far inland as the central and northeastern parts of the Northern Cape, and the southwestern part of the Free State (Duncan 1996). The genus is geophytic, deciduous, and is usually winter­ growing. Lachenalia occurs in a wide range of habitats, including arid areas (western and southern Namibia, Richtersveld, western Bushmanland, Namaqualand and northwestern parts ofWestern Cape), semi-arid areas (Western Cape interior), and medium to high rainfall areas (southwestern and southern parts of Western Cape). The centre of diversity is in the Worcester grid (3319), divided between the Succulent Karoo and Fynbos biomes, in the mountains and valleys of the winter rainfall region in the southwestern part of the Western Cape. Species diversity decreases markedly toward the eastern and northern parts of its range in the Eastern and Northern Cape. According to Goldblatt & Manning (2000), Polyxena comprises five species. A number of investigations (Pfosser & Speta 1999, Pfosser et at. 2003, van der Merwe 2002) indicate that it is embedded within Lachenalia and therefore it is included within this study. A very recent paper (Manning et at. 2004) formalised the synonomisation of Polyxena into Lachenalia 2 and the transfer ofthe species to Lachenalia, but appeared too late for incorporation in this thesis. Accordingly in this thesis the species ofPolyxena are still retained under this genus. Polyxena is restricted to the mainly winter rainfall parts of Northern Cape, the western and southern parts of Western Cape, and Eastern Cape. P ensifolia has the widest distribution, extending from southwestern Namaqualand and the western Great Karoo to the southern and southeastern parts ofthe Eastern and Northern Cape.