Red List of South African Species

Alternatively, Explore species
| National Red List categories | Partners |
Critically Endangered (CR)
Assessors: Andre Coetzer
Facilitators: Mark Williams
Reviewers: Silvia Kirkman Domitilla Raimondo Rolf Oberprieler

Rationale (Changed due to Same category and criteria)

This is a highly range-restricted endemic from Limpopo Province in South Africa (EOO 4km<sup>2</sup>, AOO 8 km<sup>2</sup>). There are two locations. When the Red List status of this species was previously assessed there was only one locality known for the species, the second only having been discovered in 2013. Unfortunately, both locations fall outside officially protected areas, and are threatened by plantations and other factors associated with commercial operations (change or reduction in fire frequency, invasive species and decreased soil moisture content). In addition, the quality of the habitat is deteriorating and the two localities are severely fragmented, with little or no corridor for gene flow. The 2013 assessment inferred a decline in the number of mature individuals. It was based on observations from the 1980’s where hundreds of specimens were seen in a day, compared to the 10 to 30 specimens that are typically seen in a day during recent surveys. However, without detailed quantitative analyses this criterion cannot be used as it may well be a sampling artifact, where surveys are affected by season, weather and sampling effort. Due to the small AOO and EOO, the severely fragmented small subpopulations, and the decline in the quality of the habitat, the status remains Critically Endangered, qualifying under criterion B.

Distribution

Endemic to the Limpopo Province in South Africa, restricted to two subpopulations in the Wolkberg mountain range.

Decline

The grass covered sections of the type locality are being overgrown with bracken ferns. The effect of thick vegetation such as bracken compared to the shorter more open grass that grows in the area has not been studied, but it could be a potential threat.

Population trend

Trend

Adult numbers fluctuate from year to year. This aspect is in need of further study.

Threats

The type locality is surrounded by plantations, which prevent the dispersal of specimens, and therefore gene flow, between the subpopulations. Plantations are also known to affect the soil water content and may have a negative impact on the remaining grassland. Due to the risk of damage to the plantations, the fire regime for both locations is no longer natural.

Conservation

Encroachment by plantations and fire frequency need monitoring. A buffer zone from the exotic plantation trees will help to protect the habitat. Further research, and a better understanding of the AOO, specifically at the new locality, are required.

References 

[@book{772,
 address = {Johannesburg &Cape Town},
 author = {Mecenero, S., Ball, J.B., Edge, D.A., Hamer, M.L., Henning, G.A., Krüger, M., Pringle, E.L., Terblanche, R.F. & Williams, M.C. (eds)},
 publisher = {Saftronics (pty) Ltd and  Animal Demography Unit, University of Cape Town},
 title = {Conservation assessment of butterflies of South Africa, Lesotho and Swaziland: Red List and Atlas.},
 year = {2013}
}
,@book{772,
 address = {Pretoria},
 author = {Henning, G.A., Terblanche, R.F. & Ball, J.B. (eds)},
 publisher = {South African National Biodiversity Institute},
 title = {South African Red Data Book: butterflies. SANBI Biodiversity Series},
 year = {2009}
}
,@article{772,
 author = {SANBI},
 journal = {South African National Biodiversity Institute},
 pages = {0},
 title = { Vegetation Map of South Africa, Lesotho and Swaziland [vector geospatial dataset] 2012. Available from the Biodiversity GIS website.},
 volume = {0},
 year = {2012}
}
,@phdthesis{772,
 author = {Ball, J.B.},
 school = {University of Stellenbosch},
 title = {Approaches towards a critical evaluation and update of the Red Data List of South African butterflies.},
 year = {2006}
}
,@article{772,
 author = {Coetzer, A.J.},
 journal = {Metamorphosis},
 pages = {32--27},
 title = {Life history and conservation status of <i>Alaena margaritacea</i> Eltringham, 1929 (Lepidoptera: Lycaenidae: Poritiinae).},
 volume = {26},
 year = {2015}
}
,]
Send feedback about this assessment to SANBI

Lead agencies, Partners and Funders

See the partners page