Magellanic BioProvince
This BioProvince (as defined by Armen Takhtajan) includes sub-antarctic Chile and a series of associated islands south of about 48 degrees latitude. Among the larger of these are the Falkland Islands, South Georgia Islands, South Sandwich Islands, South Orkney Islands and South Shetland Islands. Its southern boundary extends to the Antarctic Peninsula and its associated islands including the small island of Neny, which is the southern limit of vascular plants. The geology is complex and varied but parts of this zone including the Falklands comprise crystalline rocks that are thought to have made up the interior of the Gondwana supercontinent, some of which have been dated at 1100 million years old. The climate varies depending on latitude. In Tierra del Fuego, it ranges from continental in the north and east to more oceanic in the south and west. The Falklands experience a cold temperate, oceanic climate greatly influenced by cold Antarctic currents but further south, such as the South Shetland Islands, for example, temperatures are much lower. The sea around these islands is closed by ice during winter and they have an average temperature below 0°C for eight months of the year. At this latitude, some 160 km south of the Antarctic Circle, the flora is reduced to just two species - the cushion forming Colobanthus quitensis (Caryophyllaceae) and the Antarctic grass Deschampsia antarctica (Poaceae). Not surprisingly the flora in general is comparatively poor but includes a near endemic family (Misodendraceae) and a few endemic or near endemic genera including Eriachaenium, Macrachaenium (Asteraceae), Hamadryas (Ranunculaceae), Misodendron (Misodendraceae), Nanodea (Santalaceae), Saxifragella, Saxifragodes (Saxifragaceae), Tapeinia (Iridaceae) and Tetroncium (Juncaginaceae). Certain species such as Atriplex reichei, Chiliophyllum fuegianum, Descurainia antarctica, Epilobium conjungens, Festuca cirrosa, Onuris alismatifolia, Ourisia fuegiana, Poa darwinii, Poa yaganica, Senecio eightsii, Senecio humifusus and Senecio websteri appear to be strictly endemic to Tierra del Fuego but in general all of the associated islands have floras that are reminiscent of the Tierra del Fuegean flora. Nevertheless, the Falklands have a further 13 endemic vascular plants (see below) and South Georgia has one endemic vascular plant (Uncinia smithii) and two endemic mosses (Pseudodistichum and Skottsbergia). The mosses are thought to be relicts of the ancient flora of Antarctica that covered much of the Antarctic continent prior to the formation of the ice cap.
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.
Index |
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Major Ecosystems |
Endemic Vascular Plant Flora |
Endemics Flora (Falklands) |
Bryophyte Flora |
Fungus Flora |
Lichen Flora |
Invertebrate Fauna |
Amphibian Fauna |
Reptile Fauna |
Bird Fauna |
Mammal Fauna |
Conservation Status |