25 September 2008

Caladenia microchila - Western Wispy Spider Orchid

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Caladenia microchila - Western Wispy Spider Orchid

This orchid is distinguished from others by its tiny labellum, which is apparently the smallest amongst WA spider orchids and possibly Australia also. The width when flattened is only 4-5 mm (less than 1/4") and when compared to my fingers above, which are approximately 20 mm (7/8") wide, the small size of the labellum is immediately apparent.

Other characteristics of this orchid are the petals, which are held above the horizontal and the slender sepals and petals with their long wispy glad covered tips. Although known for its widespread preference for growing on limestone, in the mallee to the NE of Esperance it is more commonly found on a sandy clay loam immediately over granite. Flowering occurs in August and September, extending into October when rainfall is late and mild conditions prevail.