A range-restricted taxon endemic to the Western Cape Province of South Africa (EOO 62 km<sup>2</sup>). This taxon has not been seen for 14 years at its last two known locations, despite regular surveys. It was once quite widespread in the Western Cape Province, from Stellenbosch to Darling. Extensive searching has taken place over the last 40 years in both previously known as well as possible further suitable habitats. The taxon thus qualifies globally under the IUCN criteria as Critically Endangered (Possibly Extinct) under criterion B. No specimens have been seen since the previous assessment despite extensive searching. The last known observation was made in 2003 and the taxon has thus not been seen for 14 years. The status has therefore been changed from Critically Endangered to Possibly Extinct and is a genuine change.
Distribution
Endemic to the Western Cape Province in South Africa, on hills between Darling in the west to Mamre in the east, historically this taxon occurred near Stellenbosch as well as near Mamre.
Decline
"Habitat fragmentation due to farming, degradation, invasive alien vegetation and changed fire regimes.\n\n"
This taxon appears to be extinct. It was, in the past, severely threatened by incremental habitat destruction and degradation from agricultural activity and invasive alien vegetation. The ecosystem status of the habitat, from a vegetation perspective, is Critically Endangered. Trimen (1887) reported that he ‘found <i>Trimenia wallengrenii</i>, rather numerously, on hills near Stellenbosch.’ There have been no other records from this locality and the taxon probably no longer occurs there. Extensive agricultural activities in the area have led to the extinction of several other colonies. It had survived at a few habitats located on rough or rocky ground, which, owing to its nature, had escaped the plough. In some cases cultivated areas extended up to the borders of the few previously existing colonies. Pesticide use is a presumed threat but there is no empirical evidence to confirm this.
Conservation
The last two subpopulations were on privately owned farms. Monitoring of this taxon has not revealed any specimens in 14 years. This taxon is thus presumed to be extinct.
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title = {South African Red Data Book: butterflies. SANBI Biodiversity Series},
year = {2009}
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year = {2004}
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,]
