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Scientific Name | Aloe chortolirioides A.Berger var. chortolirioides |
Higher Classification | Monocotyledons |
Family | ASPHODELACEAE |
Synonyms | Aloe boastii Letty, Aloe chortolirioides A.Berger var. boastii (Letty) Reynolds |
National Status |
Status and Criteria | Near Threatened A2c; B1ab(iii)+2ab(iii) |
Assessment Date | 2018/11/19 |
Assessor(s) | L. von Staden, M. Lötter, J.E. Burrows & D. Raimondo |
Justification | A population reduction of 25-30% over three generations (90 years) is inferred from estimated rates of habitat loss. This taxon has a narrow distribution in South Africa (EOO 1797 km²), where it remains at between 10 and 15 locations. It continues to decline due to ongoing habitat loss and degradation. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | Mpumalanga |
Range | Mountains south of Barberton to north-western Swaziland, and westwards to Carolina. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Barberton Montane Grassland, KaNgwane Montane Grassland |
Description | Mistbelt grassland, wedged between rocks on slopes and mountaintops. |
Threats |
| In the mountains around Barberton and Bulembu in Swaziland, 39% of this taxon's montane grassland habitat has been converted to timber plantations, and outside protected areas, only small fragments of natural grasslands remain intact. These fragments continue to be degraded due to spreading alien invasive plants - predominantly escaped pine seedlings, but also many other weedy species that are progressively outcompeting native species, particularly in areas where fires are excluded due to the risk to plantations and other private property.
This taxon relies on fires to stimulate flowering, and therefore in areas where fires are excluded there is reduced recruitment due to lowered seed set as well as local extinctions of pollinators (Craib 2005). In other areas, particularly fire breaks, too frequent burning also has a negative impact on the population as immature individuals are not fire resistant and are killed by fires, resulting in these subpopulations consisting almost entirely of old plants (Craib 2005).
In Swaziland, this taxon has lost habitat to urban expansion around Mbabane, but overall, the impact of habitat loss and degradation on the population is less severe than in South Africa, with the global estimate of habitat loss being less than 30%. Large areas of suitable habitat is protected in the Malolotja Nature Reserve. |
Population |
Recent field surveys recorded seven extant subpopulations in South Africa. Subpopulations are generally small, consisting of a few hundred individuals or less, but not enough population counts have been done to confidently estimate the size of the population. It has also been recently recorded in Malolotja Nature Reserve in Swaziland. Intact habitat still exists at four other localities known through historical records in South Africa and two in Swaziland, and this taxon is possibly still present in these areas, but field surveys are needed to confirm this. Based on geographic isolation and threats, it is estimated that there are between 10 and 15 locations in South Africa, and between three and five locations in Swaziland.
Comparative land cover datasets from 1990 and 2014 indicate ongoing habitat loss across this taxon's range, with habitat transformation increasing from 27% to 29% over this 14 year period. A continuing population decline is inferred from ongoing habitat loss and degradation. In South Africa, the population of this long-lived taxon (generation length 30 years) is estimated to have declined by 25-30% in the past three generations, based on the rate of habitat loss recorded between 1990 and 2014. Globally, however, population reduction over the past three generations is not suspected to exceed 20%.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Aloe chortolirioides A.Berger var. chortolirioides | VU A2c | Raimondo et al. (2009) | | Aloe chortolirioides A.Berger var. chortolirioides | Not Threatened | Hilton-Taylor (1996) | |
Bibliography |
Craib, C. 2005. Grass Aloes in the South African Veld. Umdaus Press, Hatfield.
Glen, H.F. and Hardy, D.S. 1987. Nomenclatural notes on three southern African representatives of the genus Aloe. South African Journal of Botany 53(6):489-492.
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
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.
Smith, G.F., Steyn, E.M.A., Victor, J.E., Crouch, N.R., Golding, J.S. and Hilton-Taylor, C. 2000. Aloaceae: The conservation status of Aloe in South Africa: an updated synopsis. Bothalia 30(2):206-211.
Van Wyk, B.-E. and Smith, G. 2003. Guide to aloes of South Africa. (2nd ed.). Briza Publications, Pretoria.
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Citation |
| von Staden, L., Lötter, M., Burrows, J.E. & Raimondo, D. 2018. Aloe chortolirioides A.Berger var. chortolirioides. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2023/12/08 |
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