The dorsal sepal is erect at its base but then arches forward, forming a hood over the labellum and has a threadlike tip, 7–14 mm (0.3–0.6 in) long.

[2][3][4] Pterostylis metcalfei was first formally described by David L. Jones in 1997 from a specimen collected by Peter Metcalfe on Doughboy Mountain, about 10 km (6 mi) south of Wongwibindi station, on the road to Wollomombi, on 8 May 1994.

[5] In 2002, Jones and Clements transferred the species to the genus Diplodium[6][7] but the move has not been accepted by the Australian Plant Census[1] nor by the Royal Botanic Gardens, Kew.

[8] The specific epithet (metcalfei) honours the collector of the type specimens, Peter Metcalfe.

It is found on ridges and slopes with well drained soil derived from granite and basalt, growing among grass and shrubs.