Rationale
(Changed due to Same category but change in criteria)
Pseudagrion newtoni is known from only a few specimens. It is currently known to exist in only one location, where it is abundant, and it is expected to occur elsewhere in the area because extensive alien invasive tree removal is underway to improve habitat there. It is clear that the population has suffered a severe decline in the recent past. In addition to the species' natural rarity, its specialized riparian habitat (tall grasses) is under threat from increasing pressure from domestic livestock (especially cattle) visiting the water's edge. Not listed as Endangered because it occurs in a type of general habitat that is very extensive and has not been fully explored and because the removal of alien trees has an extremely beneficial effect on this species; there is a trade-off between improvement of habitat by tree removal and deterioration through overgrazing. It is assessed as Vulnerable based on its restricted range.
Distribution
This species is endemic to South Africa. The type series is from Nqutu, KwaZulu-Natal (Pinhey 1962) but the species has not been rediscovered in the area. This area is now heavily grazed by livestock. Prior to 1962, there are isolated records from the Western Cape, eastern Cape and KwaZulu-Natal, although the Cape records are doubtful taxonomically. After intensive searches over many years, the species was only rediscovered (at 1,300 m asl) in January 2001, in Mpumalanga by M.J. Samways.
Population size is estimated to be around 2,000 (per generation) and currently stable.
Threats
With more extensive and intensive livestock pressure, the grasses on the banks of rivers have become increasingly cropped and trampled. This may be synergistic with other impacts such as the growth of alien invasive riparian vegetation. The type locality is highly threatened as a result of the above factors. However, the population appears to be stabilized and it is also suspected that it is present at other localities, where it has not yet been discovered.
Conservation
This species is not known to occur within any protected areas. More searches are required to discover further subpopulations, especially in reserves. Fencing off portions of the riverbank is recommended. Translocation to a reserve is also a consideration. Removal of alien invasive trees has greatly benefited this species, as the 2001 Mpumalanga site was formerly invaded by Acacia mearnsii. Indeed, it is only known from this restored site.
[@article{4730,
author = {Samways, M.J.},
journal = {Odonatologica},
pages = {341--368},
title = {National Red List of South African Odonata},
volume = {35},
year = {2006}
}
,@article{4730,
author = {Samways, M.J.},
journal = {Odonatologica},
pages = {13--62},
title = {Diversity and conservation status of South African dragonflies (Odonata)},
volume = {28},
year = {1999}
}
,@book{4730,
address = {Nylstroom},
author = {Tarboton, W. and Tarboton, M.},
publisher = {Privately published by the authors},
title = {A fieldguide to the damselflies of South Africa},
year = {2005}
}
,@article{4730,
author = {Samways, M.J.},
journal = {African Entomology},
pages = {43--52},
title = {A strategy for national red listing invertebrates based on experiences with Odonata in South Africa},
volume = {10},
year = {2002}
}
,@article{4730,
author = {Samways, M.J.},
journal = {Biodiversity and Conservation},
number = {9},
pages = {2575--2586},
title = {Honing Red List assessments of lesser known taxa in biodiversity hotspots},
volume = {16},
year = {2007}
}
,@article{4730,
author = {Samways, M.J.},
journal = {International Journal of Odonatology},
pages = {255--262},
title = {Critical species of Odonata in southern Africa},
volume = {7},
year = {2004}
}
,@electronic{4730,
address = {http://www.iucnredlist.org},
author = {IUCN},
title = {IUCN Red List of Threatened Species (ver. 2010.3)},
year = {2010}
}
,@article{4731,
author = {Samways, M.J. and Taylor, S.},
journal = {South African Journal of Science},
pages = {78--80},
title = {Impacts of invasive alien plants on red-listed South African dragonflies (Odonata)},
volume = {100},
year = {2004}
}
,@article{13257,
author = {Samways, M.J., Taylor, S. and Tarboton, W.},
journal = {Conservation Biology},
pages = {1329--1330},
title = {Extinction reprieve following alien removal},
volume = {19},
year = {2005}
}
,]
