The genus Gloriosa (Colchicaceae) – ethnobotany, phylogeny and taxonomy Alfred Maroyi Thesis committee Thesis supervisor Prof. dr. L.J.G. van der Maesen Professor of Plant Taxonomy and Geography Wageningen University Thesis co-supervisor Dr. L.W. Chatrou Associate professor, Biosystematics Group Wageningen University Other members Prof. dr. E.F. Smets, Netherlands Centre for Biodiversity and Leiden University Dr. ir. R.H.M.J. Lemmens, PROTA Network Europe Office, Netherlands Prof. dr. K.E. Giller, Wageningen University Dr. M.J.M. Smulders, Wageningen University This research was conducted under the auspices of the Research School of Biodiversity. The genus Gloriosa (Colchicaceae) – ethnobotany, phylogeny and taxonomy i Alfred Maroyi Thesis submitted in fulfillment of the requirements for the degree of doctor at Wageningen University by the authority of the Rector Magnificus Prof. dr. M.J. Kropff, in the presence of the Thesis Committee appointed by the Academic Board to be defended in public on Tuesday 29 May 2012 at 11 a.m. in the Aula. ii Alfred Maroyi The genus Gloriosa (Colchicaceae) – ethnobotany, phylogeny and taxonomy 194 pages Thesis, Wageningen University, Wageningen, NL (2012) With references, with summaries in English and Dutch. ISBN 978-94-6173-244-6 iii Dedicated to my beloved soul mate and wife, Vongai Maroyi iv Contents Contents Chapter 1: General introduction 1 Chapter 2: Gloriosa superba L. (Colchicaceae): remedy or poison? 13 A. Maroyi and L.J.G. van der Maesen 2011. Journal of Medicinal Plant Research 5: 6112-6121 Chapter 3: Gloriosa superba L. (Colchicaceae): ethnobotany and economic importance 26 A. Maroyi and L.J.G. van der Maesen (in press). XIXth AETFAT Proceedings/Plant Ecology and Evolution Chapter 4: Systematic studies in the Gloriosa superba L. complex (Colchicaceae): a re-assessment of species boundaries 46 A. Maroyi, R.G. van den Berg and L.J.G. van der Maesen. Submitted to Plant Ecology and Evolution Chapter 5: Gloriosa and Littonia (Colchicaceae): delimitation and phylogenetic relationships based on trnL-trnF sequences 65 A. Maroyi, R. A. Wilschut, L.J.G. van der Maesen and L.W. Chatrou Chapter 6: Revision of Gloriosa L. (Colchicaceae) 77 A. Maroyi and L.J.G. van der Maesen Chapter 7: The genus Gloriosa L. (Colchicaceae): valid species names 149 A. Maroyi and L.J.G. van der Maesen Chapter 8: General discussion 156 References 162 Appendix 1 180 Summary 182 Samenvatting 184 Acknowledgements 186 Curriculum vitae 188 Education certificate 192 Index to species names 193 v Chapter 1: General introduction Chapter 1 General introduction Short, erect, non-climbing Gloriosa carsonii Baker, photograph taken by Prof. L.J.G. van der Maesen, 60 km E of Harare, Zimbabwe 1 Chapter 1: General introduction INTRODUCTION In this thesis, the results of morphological and phylogenetic studies on the genus Gloriosa L. (family Colchicaceae) are presented. Also included is an extensive review of ethnobotanical, horticultural and commercial uses of G. superba L., a commercial source of colchicine. Colchicine is an important pharmaceutical chemical with a wide range of domestic and industrial applications. The overall aim of this study was to revise the genus Gloriosa over its distributional range and to evaluate its classification and phylogeny. Documentation of the economic uses of G. superba, a valuable medicinal plant in South Africa, tropical Africa and Asia was also perceived to be essential in understanding the biology of the species. Colchicaceae and Gloriosa will be introduced briefly, as well as the research questions and research methodology. This introduction is concluded with an outline of the thesis. Taxonomic history of the family Colchicaceae The family Colchicaceae has undergone several taxonomic changes since its description by de Candolle in 1805. Baker (1879, 1897, 1898) included Colchicaceae in the family Liliaceae sensu lato, a heterogenous group (Dahlgren et al. 1985) that included many other distantly related families, in the sense of recent phylogenetic classification such as APG III (2009). In the first comprehensive monographic treatment of Liliaceae, Baker (1879) considered Colchicaceae as one of the three main suborders or divisions of the family Liliaceae based upon variation in structure of fruit, style and anthers. Suborder a included members of the family Liliaceae sensu stricto characterised by loculicidal capsule, an undivided style and introrse anthers. Suborder b included members of the family Colchicaceae characterised by septicidal capsule, a tripartite style and extrorse anthers. Suborder c included members of the family Asparagaceae characterised by baccate fruits. Based on these differences, Baker (1897, 1898) treated Colchicaceae, Asparagaceae and Liliaceae sensu stricto as suborders or series of the family Liliaceae. He subdivided Colchicaceae into two tribes: Anguillarieae D.Don, characterised by bulbs or corms as its rootstock, a loculicidal to septicidal capsule and perianth segments narrowed into a distinct claw; and Uvularieae A.Gray, characterised by a tuberous rootstock or creeping rhizome and a loculicidal capsule. From its establishment, there were two conflicting opinions: whether to treat Colchicaceae as a subfamily of Liliaceae (Baker 1879, 1897, 1898), or as a separate family (de Candolle 1805; Dahlgren et al. 1985). The problem with Colchicaceae at this stage was, therefore, mainly of rank rather than circumscription. 2 Chapter 1: General introduction The subdivision of Colchicaceae proposed by Baker (1879, 1897, 1898) was followed by that of Krause (1930) who assembled distant genera such as Androcymbium Willd. (now included in Colchicum L.), Angullaria R.Br. (now included in Wurmbea Thunb.), Baeometra Salisb. ex Endl., Burchardia R.Br., Dipdax Laws. ex Salisb. (now included in Onixotis Raf.), Iphigenia Kunth, Neodregea C.H.Wright and Ornithoglossum Salisb. into the tribe Anguillarieae. Colchicum constituted a tribe of its own, Colchiceae Rchb., and Gloriosa was grouped with Littonia Hook. (now included in Gloriosa) and Sandersonia Hook. in Uvularieae tribe. Krause (1930) included these three tribes in a large, heterogenous subfamily Melanthioideae characterised by free styles, capsular fruits and rhizomatous rootstock. Hutchinson (1934, 1959) restricted the scope of tribe Anguillarieae to comprise only genera with ebracteate inflorescence, i.e. Angullaria (now included in Wurmbea), Baeometra, Dipdax (now included in Onixotis), Neodregea, Onixotis and Wurmbea. The bracteate genera such as Androcymbium (now included in Colchicum), Burchardia, Camptorrhiza Hutch., Iphigenia and Ornithoglossum were placed in a new tribe, Iphigenieae Hutch. Colchicum was retained in the original Colchiceae. Gloriosa, Hexacyrtis Dinter, Kreysigia Rchb. (now a synonym of Schelhammera R.Br.), Littonia (now included in Gloriosa), Sandersonia, Schelhammera, Uvularia L. and Walleria Kirk (now a member of the family Tecophilaeaceae) constituted the tribe Uvularieae. A further morphological review of the tribes by Buxbaum (1925, 1936, 1937) resulted in the segregation of a new tuberous subfamily Wurmbeoideae from the rest of the rhizomatous Melanthioideae. This was a homogenous group, initially distinguished by possessing a tuberous rootstock. Buxbaum established three more or less hemisyncarpous tribes (Colchiceae, Neodregeae and Wurmbaeae) and three closely related syncarpous tribes (Baeometreae, Glorioseae and Iphigenieae) in this subfamily (Nordenstam 1982, 1986). The segregation of the subfamily Wurmbaeoideae of the Liliaceae received biochemical support showing the occurrence of colchicine and other related alkaloids with a tropolone ring as an exclusive characteristic of genera in this subfamily (Vinnersten & Larsson 2010; Wildman & Pursey 1968). Wurmbaeoideae was later accepted as a separate family Colchicaceae (Dahlgren 1975, 1980; Dahlgren et al. 1985; Huber 1969; Nordenstam 1982, 1986, 1998; Schulze 1975). Nordenstam (1982) united, and in some cases renamed Buxbaum’s tribes, reducing them to four, viz.: Anguillarieae, Baeometreae, Colchiceae and Iphigenieae. Further studies by Nordenstam (1998) expanded the family Colchicaceae to a larger and heterogeneous assemblage of 19 genera, divided into five tribes (Table 1.1). Molecular and 3 Chapter 1: General introduction biochemical analyses (e.g. Chase et al. 1993, 1995; Rudall et al. 1997; Vinnersten & Larsson 2010; Vinnersten & Manning 2007; Vinnersten & Reeves 2003) have shown the following aberrant genera to belong to family Colchicaceae: Burchardia, Disporum Salisb., Kuntheria J.G.Conran & Cliff., Schelhammera, Tripladenia D.Don. and Uvularia. Vinnersten & Manning (2007) recognised six morphologically diagnosable, monophyletic clades at tribal level in family Colchicaceae (Table 1.1). Table 1.1. Two classification systems of family Colchicaceae: (a) based on Nordenstam (1998); (b) based on Vinnersten & Reeves (2003), and Vinnersten & Manning (2007). a b Tribes Genera Tribes Genera Not placed in any tribe Burchardia Anguillarieae Baeometra Anguillarieae Neodregea Wurmbea (= Neodregea and Onixotis) Onixotis Burchardieae Burchardia Wurmbea Colchiceae Colchicum (= Androcymbium) Baeometreae Baeometra Gloriosa (= Littonia) Colchiceae Androcymbium Hexacyrtis Colchicum Ornithoglossum Iphigenieae Camptorrhiza Sandersonia Gloriosa Iphigenieae Camptorrhiza Hexacyrtis Iphigenia Iphigenia Tripladenieae Kuntheria Littonia Schelhammera Ornithoglossum Tripladenia Sandersonia Uvularieae Disporum Uvularieae Disporum Uvularia Kuntheria Schelhammera