Thelymitra × truncata, commonly called the truncate sun orchid, is a species of orchid that is endemic to south-eastern Australia. It has a single tapering, more or less flat leaf with a reddish base and up to six blue, pink or white flowers with a tube-shaped lobe on top of the anther. It is a natural hybrid between a range of species, including T. pauciflora and T. ixioides.
Thelymitra × truncata is a tuberous, perennial herb with a single more or less flat or channelled, tapering linear to lance-shaped leaf NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide with a reddish base. Up to six or more pale to deep blue, pinkish or sometimes white flowers NaNsigfig=1NaNsigfig=1 wide are arranged on a flowering stem NaNsigfig=1NaNsigfig=1 tall. There are one or two bracts along the flowering stem. The sepals and petals are NaNsigfig=1NaNsigfig=1 long. The column is a similar colour to the petals and NaNsigfig=1NaNsigfig=1 long. The lobe on top of the anther is tube-shaped with a dark collar and a yellow tip. The side lobes have mop-like tufts of white hairs on their ends. Flowering occurs from October to December. The plants are variable, due to crossing between a range of species to produce this hybrid.[1] [2]
Thelymitra × truncata was first formally described in 1917 by Richard Sanders Rogers from a specimen collected near Myponga and the description was published in Transactions and Proceedings of the Royal Society of South Australia.[3] [4] The specific epithet (x truncata) is a Latin word meaning "to maim or shorten by cutting off",[5] referring to the shaped of the middle lobe on top of the column.
The truncate sun orchid is widespread but uncommon, growing in heath, woodland and open forest. It occurs in southern New South Wales, most of Victoria, south-eastern South Australia and in Tasmania.