For instance, the occurrence of apomixis allows the recognition of large numbers of agamospecies, and such taxa have helped to bolster genera such as Ranunculus and Potentilla.
[1] The introduction of infrageneric taxa (such as the subgenus, section and series) in the 19th century by botanists including Augustin Pyrame de Candolle allowed the retention of large genera that would otherwise have become unwieldy.
[1] According to a 2004 analysis by the botanical taxonomist David G. Frodin, a total of 57 genera of flowering plants contain at least 500 species.
The actual numbers of species are imprecisely known also because of different approaches of taxonomists, and many of the genera have not been the subject of recent monographs.
Genera from some other groups of vascular plants (like pteridophytes), which have similarly large numbers of species, include Selaginella, Asplenium and Cyathea.