Taxonomic status of Pelargonium reniforme Curt.

Abstract

Background: Pelargonium reniforme Curt. is a morphologically variable species that many authors have attempted to split or combine. Confusion relating to the differences between the two subspecies currently included under P. reniforme has impeded attempts to assess their conservation status.  Pelargonium reniforme is closely related to  Pelargonium sidoides;  the two species are indistinguishable when not flowering and their distributions overlap in some areas.

Objectives: With this study, we aimed to clarify the taxonomic status of the two subspecies of P. reniforme, which has relevance in terms of their conservation status.

Method: Leaf shape, petiole length, internode length and flower colour were assessed by studying herbarium specimens of the two subspecies of  P. reniforme and specimens of P. sidoides. Living specimens of the two subspecies were also examined in their natural habitat.

Results: The current investigation showed that the morphological characters used to distinguish the two subspecies of P. reniforme are too variable to separate them. Variation in some morphological characters may be related to environmental conditions.

Conclusion: The recognition of the two subspecies of P. reniforme as distinct taxa is no longer justified.