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Geographical variation in flower color of a plant species may reflect the outcome of selection by pollinators or may reflect abiotic factors such as soil chemistry or neutral processes such as genetic drift. Here we document striking geographical structure in the color of capitula of the endemic South African grassland daisy Gerbera aurantiaca and ask which of these competing explanations best explains this pattern. The color of capitula ranges from predominantly red in the southwest to yellow in the center, with some northern populations showing within-population polymorphism. Hopliine scarab beetles were the most abundant flower visitors in all populations, apart from a yellow-flowered one where honeybees were frequent. In a mixed color population, yellow, orange and red morphs were equally attractive to hopliine beetles and did not differ significantly in terms of fruit set. Beetles were attracted to both red and yellow pan traps, but preferred the latter even at sites dominated by the red morph. We found no strong associations between morph color and abiotic factors, including soil chemistry. Plants in a common garden retained the capitulum color of the source population, even when grown from seed, suggesting that flower color variation is not a result of phenotypic plasticity. These results show that flower color in G. aurantiaca is geographically structured, but the ultimate evolutionary basis of this color variation remains elusive.

A new South African endemic species, Gerbera sylvicola is described and illustrated, with data provided on its morphology, ecology and distribution. The species appears to be closely related to G. kraussii and whilst it shares felted and prominently veined abaxial leaf surfaces, several ecological, reproductive and vegetative features clearly distinguish it. Its affinities are discussed.

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A newly discovered South African species of Watsonia Miller (1758: 184), family Iridaceae Jussieu (1789: 57), was described as Watsonia palustris Goldblatt & Manning (2016: 151). During the process of digitizing Watsonia holdings in the Bews Herbarium (NU) we realised that this name is illegitimate according to Art. 53.1 of the ICN (McNeill et al. 2012). Watsonia palustris Goldblatt & J.C.Manning is a later homonym of W. palustris Persoon (1805:43), in itself a superfluous name for Dierama pendulum (Linnaeus f. 1781: 91) Baker (1877: 99). We present a replacement name for this taxon here.