Where does the taxonomy of Streptocarpus stand at the moment, are any more changes as dramatic as the inclusion of Saintpaulia to be expected in future? My answer to this is that we do not know!
DNA analysis of Streptocarpus was initially based on the sequencing of a few genes of every species, the phylogenetic analysis of the generated sequence data, followed by an interpretation of the groups of species identified by these analyses into sections. As DNA sequencing technologies advance to enable the sequencing of whole plant genomes (in other words sequencing all of the DNA contained in the nucleus, the chloroplasts and the mitochondria) followed by phylogenetic analysis of these data, this vast increase in DNA sequence data will allow scientists to establish the relationships between species even more accurately in the genus Streptocarpus. This may then lead to a refinement in the position of species and sections within the genus. I personally do not anticipate any major changes as the big subdivisions are not likely to change, but these DNA technologies are great for analyzing aspects such as ancient hybridization, and given the regular presence of hybrids where two species co-occur in the field, it may be that some species and sections may prove to be of hybrid origin and this may then have taxonomic implications.
Recently, whole genome sequencing of a few species of Streptocarpus Section Saintpaulia have been performed which has given huge amounts of genetic information. Streptocarpus teitensis (Kyalo et al., 2018) and four populations of Streptocarpus ionanthus (Kyalo et al., 2020) have been sequenced showing the close relationship between Streptocarpus ionanthus subspecies relative to the more distantly related Streptocarpus teitensis. A larger analysis of the Streptocarpus ionanthus complex in relation to where they occur i.e. their biogeography (Kyalo et al., 2022) gives important insights into the evolution of the members of Streptocarpus Section Saintpaulia. However, this research is expensive, and major conclusions cannot be made before all of the extant species have had their genomes sequenced. This genomic information will also lead to a better understanding of the genetic control of flower shape and colour which would be of benefit to the hybridizer.
Another method for phylogenetic analysis using the RAD Seq technique shows good potential for better phylogenetic analysis of Streptocarpus and this will certainly be employed to analyse relationships in closely related groups in the genus (Chen et al., 2018)
There has been important research conducted on the phyllomorphy development of Streptocarpus seedlings (Nishii & Nagata, 2007, Tonnini et al., 2010) and this research will lead for a further understanding of the growth of Streptocarpus in cultivation.