1. Biodiversity Research Centre, Department of Natural Resources Sciences, Namibia University of Science and Technology, Windhoek, Namibia
2. Departamento de Biologia, Faculdade de Ciências Naturais, Universidade Agostinho Neto, Luanda, Angola
3. Centro de Estudos e Pesquisa, Instituto Superior Politécnico Tundavala, Lubango, Angola
4. Independent Researcher, Windhoek, Namibia
5. H.G.W.J. Schweickerdt Herbarium, Department of Plant and Soil Sciences, University of Pretoria, Pretoria, South Africa
6. Babylonstoren Farm, Simondium, South Africa
7. Department of Biodiversity and Conservation, University of the Western Cape, Bellville, South Africa