[1] Univ Port Elizabeth, Terr Ecol Res Unit, ZA-6000 Port Elizabeth, South Africa
[2] Univ Port Elizabeth, So African Hotspots Program Conservat Int, Dept Bot, ZA-6000 Port Elizabeth, South Africa
[3] New S Wales Natl Parks & Wildlife Serv, Armidale, NSW 2350, Australia
[4] Univ Cape Town, Dept Bot, Inst Plant Conservat, ZA-7701 Rondebosch, South Africa