|Scientific Name:||Schefflera procumbens (Hemsl.) F.Friedmann|
Geopanax procumbens Hemsl.
|Taxonomic Notes:||The family of the Araliaceae is assigned to different orders depending on the classification system. The Thorne system, the Dahlgren system and the Young system assign the family to the Araliales. The Takhtajan system and the Cronquist system suggest the order of the Apiales.|
|Red List Category & Criteria:||Critically Endangered B1ab(iii)+2ab(iii) ver 3.1|
|Assessor(s):||Ismail, S., Huber, M.J. & Mougal, J.|
|Reviewer(s):||Gibbs, D. & Lutz, M.L.|
Schefflera procumbens is restricted to three sites on Silhouette, Seychelles. The extent of occurrence (EOO) and the area of occupancy (AOO) are estimated to be less than 20 km² and 10 km² respectively. The invasive species Clidemia hirta and Lantana camara are present in the habitat. Although the situation seems to be stable, the quality of habitat could deplete. The population seems to be healthy and S. procumbens regenerates well from shoots. It went extinct on Mahé during the past 100 years. The reasons and rates of decline that have lead to the extinction on Mahé and to the small present population on Silhouette are not exactly known. The main reason for extinction on Mahé is certainly the destruction of the original forest during the period of the cinnamon oil industry that needed high amounts of fuel wood. As there are still several plausible threats occurring, one has to suspect an ongoing decline. Plausible threats are: competition pressure through invasive species, poor sexual reproduction, low genetic variability and limited dispersal. One single incident could wipe out the total population. It is therefore listed as Critically Endangered.
|Previously published Red List assessments:|
|Range Description:||This species is endemic to the Seychelles. It is only known from three sites on Silhouette (Friedmann 1994, J. Gerlach pers. comm. 2006). The entire area of Silhouette is 20 km² (National Statistics Bureau 2005). The EOO and AOO are estimated to be less than 20 km² and 10 km² respectively. In 1901, the species was collected on Mahé by Thomasset (Summerhayes 1931), but it has not been recorded on Mahé since that collection.|
Native:Seychelles (Seychelles (main island group))
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||No precise data on the population size is available, but it is thought to be very small. Historically, this species was also known from Mahé (Cascade Estate) (Thomasset 1901 in Summerhayes 1931). However is has not been recorded there since the collection in 1901. The only remaining individuals are now confined to Silhouette. The population seems to be healthy and the plant regenerates well from shoots (J. Gerlach pers. comm. 2006).|
The population on Silhouette is very small and it is restricted to three sites in close proximity of each other (Friedmann 1994, J. Gerlach pers. comm. 2006). Based on the eight times larger area of Mahé, it is suspected that the subpopulation on Mahé was a respectable fraction of the total population. A total population reduction of 50% over the past 100 years can be estimated.
|Current Population Trend:||Unknown|
|Habitat and Ecology:||This species occurs in moist forest at intermediate to high altitudes, 400-700 m. It is frequently found climbing on the trunks of trees but has also been found growing on and among rocks or rough cliffs (Carlström 1996). It regenerates well from shoots. Sexual reproduction cannot be observed.|
|Major Threat(s):||Plausible threats to this species are competition pressure through invasive species, poor sexual reproduction, low genetic variability and limited dispersal. The main threat is its very restricted range. The reasons for extinction on Mahé are not exactly known; the main reason might have been the destruction of the original forests for the cinnamon oil industry. But there must have been other threats affecting the remaining individuals in inaccessible areas. Competition pressure through invasive species such as Clidemia hirta and Lantana camara is the major actual and future threat to this species (Carlström 1996). The effects of these invasive species on S. procumbens are uncertain. Although the situation seems to be stable, the quality of habitat could deplete.|
|Conservation Actions:||Not present in protected areas. New data on population urgently needed.|
|Citation:||Ismail, S., Huber, M.J. & Mougal, J. 2011. Schefflera procumbens. The IUCN Red List of Threatened Species 2011: e.T33547A9791562.Downloaded on 18 December 2017.|