A photograph of a yellow sun orchid is July’s winning photograph and was taken by John Badger.
It is not difficult to identify a yellow sun orchid because amongst all of the Australian Thelymitras there are only two true yellow sun orchids. These are Thelymitra antennifera and the less common and very different, smaller T. flexuosa.
T. antennifera has a distinctive column with two reddish brown appendages resembling rabbit’s ears henc the connom name of Rabbit Ears Sun Orchid. Another common name Lemon Sun Orchid refers to the faint but recognisable lemon scent produced by the flower but as to why it should ever have been singled out from the other sun orchids to be called Women’s Caps1, I cannot tell.
Prior to flowering, the leaf distinguishes this sun orchid from others. Though having a red base like some of the other sun orchid, it is thin and rounded ie filiform and terete. Further, the closed buds are dark pink with lemon yellow margins of the sepals.
It should be noted that both T. carnea and T. rubra can on rare occasions produce a pale yellow variety but they will have all the features of their respective species. Also a T antennifera hybrid, T. x macmillanii, can on occasions produce yellow flowers.
- R. Bates (2011) South Australia’s Native Orchids DVD
- David L. Jones (2006) A Complete Guide to Native Orchids of Australia
- 1The Australian Zoologist 1945 – 1951 Vol II Issued by the Royal Zoological Society of NSW http://biodiversitylibrary.org/page/39059910#page/7/mode/1up accessed 1st August 2014