The consequences of specialization for pollination in a rare South African shrub,Ixianthes retzioides (Scrophulariaceae)

@article{Steiner2004TheCO,
  title={The consequences of specialization for pollination in a rare South African shrub,Ixianthes retzioides (Scrophulariaceae)},
  author={K. Steiner and V. Whitehead},
  journal={Plant Systematics and Evolution},
  year={2004},
  volume={201},
  pages={131-138}
}
Ixianthes retzioides is a rare South African shrub with large yellow oil-secreting flowers. Populations studied previously revealed low levels of reproductive success and the absence of a specialized oil-collecting pollinator. We report the discovery of a population in which the predicted specialist pollinator,Rediviva gigas, is present. The presence of this oil-collecting bee resulted in a mean fruit set per plant of 97.2 ± 8.3% (N = 9) and a mean seed set of 331.6 ± 162.6 (N = 52). This… Expand

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