The genus Sabatia includes 17 species that are limited to North America and the West Indies.
Angiosperms take many adaptive tacks to maximize pollen flow between plants and minimize 'selfing'.
This insures high levels of genetic variation that are required for selective response to changing conditions. This is accomplished in S. campestris populations by sequential anthesis . Anthers dehisce shortly after the flower opens but, as this is happening, the two stigmatic branches of the style are twisted together and unexposed. Once pollen has been removed from a given flower, the stigmatic braches untwist and take on a more receptive position. A look at these flowers on side view suggests epigyny in that there is an expansion between the perianth-part extensions and the pedicel.