The recent evidence that extant cycads are not living fossils triggered a renewed search for a better understanding of their evolutionary history. In this study, we investigated the evolutionary diversification history of the genus Encephalartos, a monophyletic cycad endemic to Africa. We found an antisigmoidal pattern with a plateau and punctual explosive radiation. This pattern is typical of a constant radiation with mass extinction. The rate shift that we found may therefore be a result of a rapid recolonization of niches that have been emptied owing to mass extinction. Because the explosive radiation occurred during the transition Pliocene–Pleistocene, we argued that the processes might have been climatically mediated.

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Soutpansberg Mountain range is one of the main biodiversity hotspots in South Africa and it is located in Limpopo Province. It possesses high diversity of flora and fauna. Communities surrounding this mountain have long benefited from the ecosystem services that the area provides. It is of importance to determine the threat status of plant species endemic to this mountain range that has been a great source of ecosystem services. Twenty-two endemic vascular plant species of the mountain range have been identified. In this study we use the South African National Biodiversity Institute (SANBI) current 2017 version Red List categories to determine the threat status of plant species endemic to Soutpansberg Mountain range. SANBI is the national body in South African that is responsible for national threat assessment for plant and animal species and they also provide data to IUCN (International Union ofC onservation of Nature) on threat status of plant and animal taxa found in South Africa. We calculated the categorical percentages of threat status of endemic vascular plants species of Soutpansberg Mountain range and the threats these plant species are facing were gotten from SANBI Red List. This study showed that over 50% of the plant species endemic to this area are of conservation concern meaning they deserve conservation attention. Majority of threats are due to anthropogenic pressure. This implies that the endemic flora of this region is facing risk of extinction. This study recommends protection of all the endemic plant species of this mountain range in order to prevent theirf uture extinction.

Cycads are the most threatened group of plants in the world and there are a wide range of ecological and anthropological forces responsible for the extinction risk of these taxa. South Africa is a global hotspot of cycad diversity and the country’s cycads are facing high extinction risk. In this study we sampled a population (n=34) of Encephalartos transvenosus Stapf & Burtt Davy, a cycad species endemic to Limpopo Province, South Africa. The population was located on the Soutpansberg mountain range in the Mutale local municipality. A survey was conducted to quantify the threats to the population.  Forty-seven percent of the plants had been damaged by bark harvesting for traditional medicine, and the population showed a mortality rate of 9%. We recommend further studies at a range of Encephalartos transvenosus populations to provide a broader understanding of impacts of harvesting and population trends. We also recommend community based initiatives to enhance the protection of this species in the communities in which they are found.

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