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This is the third of the major habitats to be discussed.
Orchids characteristic of this zone include the Cebolletae and Plurituberculata oncidiums, Laelia dayana, pumila
lundii and milleri, Leptotes bicolor, Cattleya walkeriana and nobilor, schomburgkia, Dendrobium speciosum and biggibum,
and Cymbidium suave, madidum and canalicculatum.
The habitat characteristically occurs in inland rain shadow areas, at an altitude of
500 to 1000 metres above sea level. Typical locations are coastal India, in Brazil including the central plateaus
of Minas Gerais, Goyas and Matto Grosso, and inland Australia, west of the Great Divide.
It is characterised by:-
- hot days followed by very cool nights
- Humidity is low during the day, but is high at night.
- Temperatures are warm, with significant diurnal variation.
- the amount of water is the major determinant of the number and type of orchids found
- many plants have developed water conservation adaptations to survive significant amounts
of aridity.
The majority of orchids found are terrestrials with epiphytes found bordering streams
where free water is available, with higher levels of humidity.
Growth and development, especially for the terrestrials, can be rapid, depending on the
length of the wet season.
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