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.

The plants are variable, due to crossing between a range of species to produce this hybrid.

[2][3] 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.

[4][5] The specific epithet (x truncata) is a Latin word meaning "to maim or shorten by cutting off",[6] referring to the shaped of the middle lobe on top of the column.

[5] The truncate sun orchid is widespread but uncommon, growing in heath, woodland and open forest.