Determining regions of higher extinction risk occurrences in South African cycads

Abstract

Extinction crisis in South African cycads has been very high in recent times. This study used comprehensive distribution records of cycads that occurred in South Africa. The records obtained from the South African national herbarium named South African National Biodiversity Institute (sanbi) through the herbarium sheets were used to determine the regions of higher extinction crisis in South Africa. The threat status of the herbarium taxa was obtained from iucn 2019 version and was analysed. Threats to these taxa were extracted from iucn and the numbers of taxa facing each threat were determined to unravel the prominent threats. The herbarium records were used to construct a species distribution map for all the cycads in South Africa and another map for Critically Endangered and Extinct South African cycads. This study revealed that regions of high species richness for South African cycads are not the same as regions with highly threatened and extinct South African cycads. Prominent threats found in this plant group are also the major threats causing extinction crisis in the highly threatened and extinct cycads that occurs in few provinces in South Africa. This study therefore recommends that conservation efforts for South African cycads should be intensified in the hotspots of highly threatened and extinct South African cycads identified in this study to further mitigate extinction crisis of South African cycads.