Taxonomy
Scientific Name
Aloe thorncroftii Pole-Evans
Higher Classification
Monocotyledons
Family
ASPHODELACEAE
National Status
Status and Criteria
Near Threatened D2
Assessment Date
2020/01/22
Assessor(s)
M. Lötter, E. van Wyk, J.E. Burrows, L. von Staden & H. Mtshali
Justification
Aloe thorncroftii is a rare and localized habitat specialist, occurring at six to eight locations. It is not currently declining, but habitat loss could lead to a rapid increase in its risk of extinction. It is however unlikely to become Critically Endangered or extinct within a short time, and therefore nearly meets the threshold for Vulnerable under criterion D2.
Distribution
Endemism
South African endemic
Provincial distribution
Mpumalanga
Range
This species is endemic to the mountains south of Barberton in eastern Mpumalanga.
Habitat and Ecology
Major system
Terrestrial
Major habitats
Barberton Serpentine Sourveld
Description
It is localized to steep rocky slopes in serpentine outcrops in montane grassland.
Threats
This species has lost some habitat to commercial timber plantations in the past, and there was significant expansion of plantations at one location on Nelshoogte Pass between 1990 and 2014. Currently, there is no severe ongoing expansion of plantations. Many locations are near areas of abandoned mines. There is a renewed interest in mining in the Barberton Mountains, and habitat loss to mining remains a potential threat. Field surveys by the Mpumalanga Parks and Tourism Agency, the local conservation authority, noted that A. thorncroftii appears to be resilient to disturbance, readily colonizing degraded sites next to roadsides, at abandoned mines as well as old plantations. Therefore it is unlikely to be negatively impacted by habitat degradation as suggested by Williamson and Balkwill (2006). As this is a rare, range restricted species that is not widely available in cultivation (according to Van Wyk and Smith 2014 it is hard to cultivate) it may also be targeted by succulent collectors.
Population

Aloe thorncroftii has a restricted distribution range, and is localized to a few serpentine outcrops in the Barberton Mountains. According to Williamson and Balkwill (2006), the population is small, consisting of between 1500 and 3000 mature individuals, and there are between four and seven subpopulations. The population is not suspected to be declining at present, but due to its localized distribution, potential threatening events such as expansion of mines or plantations, could rapidly increase its risk of extinction.


Population trend
Stable
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Aloe thorncroftii Pole-EvansNT D2Raimondo et al. (2009)
Aloe thorncroftii Pole-EvansVU D2Victor (2002)
Aloe thorncroftii Pole-EvansVulnerable Hilton-Taylor (1996)
Aloe thorncroftii Pole-EvansRare Hall et al. (1980)
Bibliography

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.


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.F. 2014. Guide to the Aloes of South Africa. (Third ed.). Briza Publications, Pretoria.


Victor, J.E. 2002. South Africa. In: J.S. Golding (ed), Southern African plant Red Data Lists. Southern African Botanical Diversity Network Report 14 (pp. 93-120), SABONET, Pretoria.


Williamson, S.D. and Balkwill, K. 2006. Factors determining levels of threat to serpentine endemics. South African Journal of Botany 72(4):619-626.


Citation
Lötter, M., van Wyk, E., Burrows, J.E., von Staden, L. & Mtshali, H. 2020. Aloe thorncroftii Pole-Evans. National Assessment: Red List of South African Plants version . Accessed on 2025/05/19

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Distribution map

© M. Lötter

© Mpumalanga Parks and Tourism Agency (M.T.P.A.)

© D.R. McKenzie


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