Aloes and Lilies of Ethiopia and Eritrea Sebsebe Demissew Inger Nordal Aloes and Lilies of Ethiopia and Eritrea Sebsebe Demissew Inger Nordal <PUBLISHER> <COLOPHON PAGE> Front cover: Aloe steudneri Back cover: Kniphofia foliosa Contents Preface 4 Acknowledgements 5 Introduction 7 Key to the families 40 Aloaceae 42 Asphodelaceae 110 Anthericaceae 127 Amaryllidaceae 162 Hyacinthaceae 183 Alliaceae 206 Colchicaceae 210 Iridaceae 223 Hypoxidaceae 260 Eriospermaceae 271 Dracaenaceae 274 Asparagaceae 289 Dioscoreaceae 305 Taccaceae 319 Smilacaceae 321 Velloziaceae 325 List of botanical terms 330 Literature 334 4 ALOES AND LILIES OF ETHIOPIA Preface The publication of a modern Flora of Ethiopia and Eritrea is now completed. One of the major achievements of the Flora is having a complete account of all the Mono­ cotyledons. These are found in Volumes 6 (1997 – all monocots except the grasses) and 7 (1995 – the grasses) of the Flora. One of the main aims of publishing the Flora of Ethiopia and Eritrea was to stimulate further research in the region. This challenge was taken by the authors (with important input also from Odd E. Stabbetorp) in 2003 when the first edition of ‘Flowers of Ethiopia and Eritrea: Aloes and other Lilies’ was published (a book now out of print). The project was supported through the NUFU (Norwegian Council for Higher Education’s Programme for Development Research and Education) funded Project of the University of Oslo, Department of Biology, and Addis Ababa University, National Herbarium in the Biology Department. What you have at hand is a second updated version of ‘Flowers of Ethiopia and Eritrea: Aloes and other Lilies’. In the preface to the 2003 version Sue Edwards and Inga Hedberg (co­editors together with Sebsebe Demissew) of Volume 6 of the Flora of Ethiopia and Eritrea wrote: “We, therefore, welcome the publication of ‘Flowers of Ethiopia and Eritrea: Aloes and other Lilies’ and hope it will inspire other authors to produce similar books for different groups of plants. That in fact has happened with the publication of ‘Field guide to Ethiopian Orchids’ by Sebsebe Demissew, Phil Cribb and Finn Rasmussen, which appeared in 2004. These books are intended to be guides useful to a wider audience than professional botanists: students, teachers, conservationists, and amateurs interested in understanding and exploring parts of the flora of Ethiopia and Eritrea. The two editions of ‘Aloes and other Lilies’ well illustrate the importance of the continued research in th Flora area. In the 6 years period from 1997 to 2003 for example two new endemic species of Aloe and two new endemic species of Chlorophytum were described. In the PREFACE 5 next 7 years period up to 2010, another six species of Aloe and one species of Chlorophytum were described – two genera where active research has taken place during the last decade. The book now contains 16 families (see further under “What is a lily?). We have also commented on the uses and conservation status of many of the groups. In addition to the introductory part (including vegetation description), this book gives descriptions and distribution maps for 200 species in 42 genera. Approximately 50% of the species are illustrated with photographs. Despite their attractive flowers, many of these species are poorly studied. As can be seen from the information on flowering periods, this is because these plants often flower at times of the year when little plant collecting is done, like the start of the rainy season and during the drier months of the year. The importance of having year­round observation and collection is emphasised. It is hoped that also this book will stimulate more people, particularly school teachers and professionals working with natural resource management, to make year­round observations of the plants growing in their areas. It is certain that more new lilies will be discovered in Ethiopia and Eritrea in the years to come, and we hope that this small book will stimulate interest in these botanical treasures. Acknowledgements The authors would like to acknowledge the support given by NUFU (Project 11/96 and 53/03) under the collaborative program between Addis Ababa University and the University of Oslo. We would like to thank the Editors of the Flora of Ethiopia and Eritrea, Dr. Inga Hedberg and Ms Sue Edwards, for giving the permission to use information from Volume 6. We are grateful to the individuals at all institutions who facilitated the smooth running of the project. The great help provided by the Curators and Keepers of the National Herbarium in Addis Ababa (ETH) and the Royal Botanic Gardens, Kew (K), is acknowledged. The latter is particularly acknowledged for providing permission to use some of the illustrations and introductory part from the book “Field guide to Ethiopian Orchids (Sebsebe Demissew et al 2004). 6 ALOES AND LILIES OF ETHIOPIA Odd E. Stabbetorp (NINA) was crucial for the handling of detailed distribution maps and information in the first edition. In this second edition we have simplified this information by plotting only the occurrence in floristic regions as delineated in Figure 2. Steven Bachman and Fisseha Getachew have assisted in this mapping project and are acknowledged. We would like to extend our thanks and appreciation to friends and colleagues that provided us with additional photos of plant species that we did not have. The most important contributors have been Mike Gilbert, Ib Friis and Christof Herrmann. A complete list of photographers is given at the end of the book. The preparation of the camera ready manuscripts for this new edition (and also for the first edition) was undertaken by the able Jan Wesenberg, to whom we express our sincere gratitude. Many thanks to many colleagues, research assistants, and students, who in one way or another have contributed to the publication of this book. Although many have helped us in this process, the mistakes or errors that may be encountered, are our own responsibility. Sebsebe Demissew, Addis Ababa University Inger Nordal, University of Oslo January 2010 INTRODUCTION 7 Introduction Ethiopia and Eritrea are two countries with varied topography and climate from hot semi­desert temperature and an altitude of 115 m below sea level in the Afar depression to cooler climates at 4620 m altitude at the top of the Semien mountains. These contrasting temperature sand altitudes coupled with geology have resulted in niches that include about 6000 species of higher plants and of which about 10–12% are endemic. Of these species ,about 1322 species are monocots (22%), with grasses accounting to 612 species (c.10%) and the remaining monocots including orchids cover about 710 species (c.12% of the flora). In this book only the monocots that might be considered as “lilies” (see p. 38) are included. In this introductory part, the many underlying factors that influence the vegetation of a given country or region that work on different time scales are briefly described. Of these, geology, geography and climate (rainfall and temperature), that have worked for a very long time, and the human influence, that has worked for a much shorter span of time are important factors. The moderate human interference in a landscape works in a way that tends to diversify the vegetation – creating more vegetation types than before the beginning of human activity – while strong and prolonged human interference can totally degrade a range of vegetation types to a badly eroded and denuded landscape with very little differentiation of the vegetation left. The main information on the geology, geography and climate included is obtained from Ethiopian sources. However, the information provided also applies to Eritrea that shares a strong similarity with northern parts of Ethiopia (mainly the Gonder, Tigray and Afar floristic regions) except for the coastal part, which is unique for Eritrea. 8 ALOES AND LILIES OF ETHIOPIA Geology Ethiopia’s and Eritrea’s geology is based on an old crystalline block, originally part of an immense area that stretched from India to Brazil and formed part of the ancient super­continent Gondwanaland. The hard crystalline rocks are mainly granites and gneisses, and contain many valuable mineral deposits. Precambrian rocks with ages of over 600 million years, found in parts of Tigray, Gonder, Gojam, Harerge, Sidamo, Bale Illubabor and Wellega floristic regions, are the oldest rocks in the country and form the basement on which younger formations lie (Ethiopian Mapping Authority, 1988). These include a wide variety of sedimentary, volcanic and intrusive rocks that have been metamorphosed to varying degrees. In the southern and western parts of the country, these have been more strongly metamorphosed than their counterparts in the north. This is mainly due to the fact that the rocks in the north have been subjected to relatively lower temperatures. Towards the end of the Precambrian, a major uplift followed by a long period of erosion took place. Sediments deposited during the Paleozoic interval (which lasted some 375 million years) have been largely removed by erosion. During the Mesozoic (starting about 225 million years ago), subsidence occurred and the sea initially spread over the Ogaden then gradually extended further north and west. As the depth of the water increased, sandstone, mudstone and limestone were deposited. As the land mass was again uplifted, sedimentation ended in the western parts of the country with the deposition of clay, silt, sand, and conglomerate from the land as the sea receded. In the south­eastern parts, gypsum and anhydrite deposits were precipitated. In the Early Cenozoic (which began 65 million years ago), extensive faulting took place. However, the major displacement along the fault systems of the Red Sea, Gulf of Aden and East African Rifts occurred later during the Tertiary. Faulting was accompanied by widespread volcanic activity which led to the deposition of vast quantities of basalt, especially over the western half of the country.