Eremaean (Central Australian) BioProvince
This BioProvince (as defined by Armen Takhtajan) comprises the central deserts of Australia including the Great Sandy Desert, Gibson Desert, Great Victoria Desert, the deserts of the Northern Territory, the Nullarbor Plain and a considerable part of the Great Artesian Basin. In the west it extends to the Indian Ocean between the Edel Peninsula and Roebuck Bay, while in the east it reaches the Darling River in New South Wales. The geology is complex and varied, but the area encapsulates Australia’s arid and semi-arid zones, which are thought to be at least 15 million years old, but considered to be relatively young in geological terms. This desert region is the driest part of Australia characterised by intense heat during the day and intense cold at night, and in fact, much of the area is in a constant state of drought. The flora is very distinctive with some 363 genera of which 102 are endemic including Astrebla, Babbagia, Dysphania, Embadium, Enchylaena, Malococera, Neurachne, Plectrachne, Rutidosis, Threlkeldia, Triodia, Uldinia and Zygochloa while the large genus Eremophila is virtually endemic. Many of these are thought to have evolved from Australia’s highly adapted, pre-arid flora. However, the main difficulty has been explaining the presence of cosmopalitan components including endemic genera of families such as Aizoaceae, Asteraceae, Brassicaceae, Chenopodiaceae and Poaceae, which are among the main constituents of all of the World’s major deserts. How was it possible for these colonisers to cross-extensive parts of the globe to become establised in Australia’s arid zone? The answer is that these cosmopolitan taxa were probably already established in Australia’s littoral habitats prior to the onset of arid conditions, where salinity and soil types impose physiological conditions similar to those of deserts.
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|