Since my early childhood, I have been fascinated by Saintpaulias, my granny grew them on her windowsill, and I also cultivated them. Through my biochemical training I became involved in DNA sequencing technologies in the 1990’s and plant molecular systematics and this led to projects on South African Streptocarpus with Michael Moeller from Royal Botanic Gardens Edinburgh and Trevor Edwards from the University of KwaZulu Natal. I was able to do fieldwork in Tanzania to view Saintpaulias in their natural habitat in 1996, undertook many expeditions in South Africa from 1999 onwards to search for South African Streptocarpus and in 2010, I was able to do fieldwork in Madagascar to see the amazing Streptocarpus there. My research was always heavily biased towards DNA sequencing and phylogenetic analysis, and this allowed me to gain considerable insights into the relationships of the species in the genus. Based on these results, I was part of the team that proposed a new taxonomy for the genus.
Thus, in a milestone publication in 2015, the taxonomy of Streptocarpus changed significantly (Nishii et al., 2015). Seven former genera were incorporated into Streptocarpus based on DNA results. Six of these genera contained very few species and were of minor horticultural importance. However, the incorporation of the seventh genus, Saintpaulia, caused major upheaval in the horticultural world. These seven genera were all previously not included in Streptocarpus because of what were thought to be significant morphological differences, yet DNA analysis showed otherwise. In this article, I wish to describe the now more broadly defined Streptocarpus.
The first Streptocarpus that was cultivated way back in the 1820’s caused significant horticultural interest and Streptocarpus since then have become important horticultural subjects. The commercial value of both species and hybrids of Streptocarpus and Saintpaulia as a part of Streptocarpus in horticulture is worth millions of dollars worldwide annually.