SU botanists contribute to magnum opus on Cape orchids

The two volumes of the orchids book.

The who’s who of South Africa’s botanical research community gathered in Kirstenbosch recently for the launch of a hefty 6,7kg book on the Cape’s orchids, to which researchers from Stellenbosch University also contributed.

The two volumes of The Cape Orchids: a regional monograph of the orchids of the Cape Floristic Region was authored by William Liltved, a highly knowledgeable amateur botanist from Noordhoek on the Cape Peninsula, and Prof Steven Johnson of the University of KwaZulu-Natal (UKZN).

More than 2000 exquisite photographs are printed on the 1048 pages of fine-art paper.

The mammoth botanical project began 22 years ago, and presents an authoritative account of the taxonomy and ecology of the 241 orchid species native to the Cape Floristic Region as well as richly illustrated accounts of the researchers and personalities that have described the Cape orchid flora since the days of Linneaus, the father of botanical classification.

“As many orchids are seriously threatened by urban expansion and some have already been driven to extinction, this book serves as a unique record of the Cape orchid flora which may never be repeated or improved upon again,” says one of the Stellenbosch University researchers who contributed to the book, Prof Dirk Bellstedt of the Department of Biochemistry.

Other Stellenbosch University researchers listed as contributors are Dr Ted Oliver and Prof Anton Pauw of the Department of Botany and Zoology. Research and field observations by Dr Allan Ellis and Dr Bruce Anderson, also of the Department of Botany and Zoology, were used in the drafting of the text.

Dr Oliver, a research associate in the Department of Botany and Zoology, is best known for his work on the Erica genus, but has a broad interest in plants, including orchids. He provided notes on taxonomy and synoptic descriptions, and assisted in the sections on the botanical history of the Cape.

Prof Pauw, a specialist on the ecology and evolution of orchids, contributed a chapter on the pollination of orchids by oil-collecting bees (Rediviva), and provided valuable field observations, editorial assistance and photographs to the chapters on Corycinae and Dispersis. He also contributed to the phylogeny of the Corycinae.

Prof Bellstedt has used DNA sequencing and phylogenetic analyses to establish the relationships of a number of Cape orchid groups much more accurately in recent years. The results of his research, and that of one of his former doctoral students, SU alumnus and plant taxonomist, Dr Benny Bytebier, is presented for the first time in this book. The new sectional classification published in his thesis was used in the chapter on the genus Disa. Dr Bytebier is now curator of the Bews Herbarium at UKZN.

The phylogenetic analysis of the genus Disa has also given important insights into factors driving speciation in orchids specifically and in the Cape Flora in general. This has shown that fire became an important factor in the evolution of orchids about 18 million years ago and these deductions were also included in the book. Dr Bytebier as the lead author and Prof Bellstedt published this research in the Proceedings of the Royal Society: Biological Sciences in 2011. This was the first time that such deductions were made from a phylogeny and this publication has been repeatedly referenced since then.

The phylogenetic work on Satyrium by another SU Alumnus Dr Timo van der Niet—now of UKZN, was also included in the comprehensive reference book.

For more information, visit http://www.capeorchids.co.za/details.htm