Thelymitra hiemalis, commonly called the winter sun orchid, is a species of orchid that is endemic to Victoria. It is a winter flowering orchid with greenish sepals and blue or mauve petals with large, irregular, darker spots.
Thelymitra hiemalis is a tuberous, perennial herb with a fleshy, channelled, dark green, linear to lance-shaped leaf NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide with a reddish base. Up to five mauve or blue flowers NaNsigfig=1NaNsigfig=1 wide are borne on a flowering stem NaNsigfig=1NaNsigfig=1 tall. The sepals and petals are NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide. The sepals are often greenish and the petals, including the labellum have irregular, darker spots. The column is white, about 4sigfig=2NaNsigfig=2 long and 2sigfig=1NaNsigfig=1 wide. The lobe on the top of the anther has a brownish back and crowded yellow or orange, finger-like calli. The side lobes have mop-like tufts of white hairs. Flowering occurs from June to August.[1] [2]
Thelymitra hiemalis was first formally described in 1988 by David Jones and Mark Clements and the description was published in The Orchadian.[3] The specific epithet (hiemalis) is a Latin word meaning "of winter".[4]
The winter sun orchid grows in heath and is only known from a few records near Portland, Anglesea, Upper Beaconsfield and Blackburn.
Thelymitra hiemalis is listed as "endangered" under the Victorian Flora and Fauna Guarantee Act 1988.