This BioProvince (as defined by Armen Takhtajan) mainly comprises the Mascarene Archipelago in the Indian Ocean. The main islands include Mauritius, Reunion and Rodriguez. It also includes the islands of Carajos and Cargados. These are mountainous volcanic islands situated on the Seychelles-Mauritius Ridge. Their soils are mainly basaltic but there are also raised coral and sandstones in places. Rain, mainly brought by the SE trade winds, varies locally but can exceed 4000 mm per year. The climate comprises a warm, wet season from November to April and a cool, dry season from May to October. Mauritius is famous or infamous for the man-induced extinction of the Dodo - a large, flightless member of the pigeon family. Unfortunately this caused the added problem that certain endemic plants such as Calvaria major (Sapotaceae) and Canarium mauritianum (Burseraceae) appear to require their seeds to pass through the bird’s alimentary canal to assist germination. Since this is no longer possible the regeneration of these plants has been retarded and could lead to their extinction. The flora has a high level of both generic and specific endemism. Of the 644 native species on Mauritius, 287 (45%) are endemic and on Rodrigues the 132 native species includes 44 (33%) endemics. Many of the endemic species seem to have originated from Madagascar while others appear to have orginated from much further afield. For example, the nearest relative to the endemic tree Acacia heterophylla found on Reunion Island occurs some 17000 km away in Hawaii (Acacia koa). This initially made little sense until it was discovered that the endemic Reunion seabird Barau's Petrol appears to be derived from the Hawaiian Petrol and this early coloniser could have transported seeds in its feathers.
The endemic plant genera include Acanthophoenix, Aeranthes, Allocalyx, Arnottia, Astiria, Badula, Berenice, Cheirolaena, Cylindrocline, Dictyosperma, Doratoxylon, Eriothrix, Faujasia, Faujasiopsis, Fernelia, Forgesia, Gymnochilus, Herya, Heterochaenia, Hornea, Hyophorbe, Latania, Mahya, Mathurina, Monarrhenus, Myonima, Myoporum, Nesocodon, Nesogenes, Parafaujasia, Pseudannona, Psiadia, Psiloxylon, Roussea, Ruizia, Scyphochlamys, Tectiphiala, Tetrataxis, Trichosandra, Trochetia and Warneckea.
The following accounts for this BioProvince have been written or will be written with particular reference to endemic and locally important species. Accounts available are displayed in green or yellow. Those displayed in red are either in the pipeline or awaiting expert contributions.
|Endemic Vascular Plant Flora|