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Scientific Name | Encephalartos arenarius R.A.Dyer |
Higher Classification | Gymnosperms |
Family | ZAMIACEAE |
Common Names | Broodboom (a), Cycad (e), Duin-broodboom (a), Dune Cycad (e) |
National Status |
Status and Criteria | Endangered A2acd; B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v); C1 |
Assessment Date | 2020/06/04 |
Assessor(s) | J.D. Bösenberg & J.S. Donaldson |
Justification | This species qualifies as Endangered under criterion A due to a continuing decline in the number of plants and the extent of habitat. Repeat photographs indicate a decline of >50% over the past 60 years. While this is less than one generation, further extrapolation is difficult and so this is treated as a minimum population reduction. It also qualifies under criterion B due to a relatively restricted range (extent of occurrence = 450 km²; area of occupancy =20 km²), occurrence at less than five locations and ongoing decline. The overall population is estimated to be <2,500 mature individuals and decline is >20% over two generations so it also qualifies under criterion C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Eastern Cape |
Range | This species is distributed in a small area of the Eastern Cape in South Africa. Subpopulations are found from west of Alexandria to Canon Rocks in the east. The main subpopulations occur near the town of Alexandria. It has been recorded from 100 to 200 m asl. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Southern Coastal Forest, Albany Mesic Thicket |
Description | Plants occur in densely wooded coastal dune thicket and coastal forest. Most of the plants occur on moderate to steep slopes in sandy soil on stabilized dunes. |
Threats |
| The major threat to this species is removal by collectors. This has been the main cause of decline over the past 50 years. Some have also been destroyed by habitat destruction (bush clearing to make way for pastures) but this has not been a major driver over the past several decades. |
Population |
The population size of Encephalartos arenarius is estimated to be 850-1,500 mature individuals. Most plants occur in the dense dune vegetation that is difficult to survey. Scattered individuals occur in agricultural lands and cleared dunes. An updated population size estimate is urgently needed for this species. This will form part of the Biodiversity Management Plan for this species.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Encephalartos arenarius R.A.Dyer | EN A2acd; B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v); C1 | Raimondo et al. (2009) | | Encephalartos arenarius R.A.Dyer | Endangered | Hilton-Taylor (1996) | | Encephalartos arenarius R.A.Dyer | Vulnerable | Hall et al. (1980) | |
Bibliography |
Coates Palgrave, M. 2002. Keith Coates Palgrave Trees of southern Africa. 3rd Edition. Struik, Cape Town.
Donaldson, J.S. 2003. Cycads. Status survey and conservation action plan. IUCN/SSC Cycad Specialist Group, Gland, Switzerland; Cambridge, UK.
Goode, D. 1989. Cycads of Africa. Struik/Winchester, Cape Town.
Goode, D. 2001. Cycads of Africa Volume I. D&E Cycads of Africa, Gallo Manor.
Hall, A.V., De Winter, M., De Winter, B. and Van Oosterhout, S.A.M. 1980. Threatened plants of southern Africa. South African National Scienctific Programmes Report 45. CSIR, Pretoria.
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
Kemp, M. 1987. Focus on Encephalartos arenarius. Encephalartos 11:4-7.
Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
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Citation |
| Bösenberg, J.D. & Donaldson, J.S. 2020. Encephalartos arenarius R.A.Dyer. National Assessment: Red List of South African Plants version . Accessed on 2025/05/17 |
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