Pterostylis auriculata is a species of orchid endemic to New Zealand. Unlike many other greenhood orchids, this species lacks a rosette of leaves but instead only has leaves on the flowering stem. All parts of the plant are glossy and there is a single green flower with a reddish tinge.
Pterostylis auriculata is a terrestrial, perennial, deciduous, herb with an underground tuber and has four glossy green leaves on the flowering stem. The leaves are lance-shaped, NaNsigfig=1NaNsigfig=1 long, NaNsigfig=1NaNsigfig=1 wide and the uppermost leaf is usually higher than the flower. There is a single glossy green flower with reddish tips. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal is narrow egg-shaped, NaNsigfig=1NaNsigfig=1 long with a sharp tip. The lateral sepals are erect, have narrow tips up to 25sigfig=1NaNsigfig=1 long and spread slightly apart from each other. The labellum is red, 10sigfig=1NaNsigfig=1 long, NaNsigfig=1NaNsigfig=1 wide and curved with a prominent mid-rib. Flowering occurs from October to November.[1] [2]
Pterostylis auriculata was first formally described in 1889 by William Colenso and the description was published in Transactions and Proceedings of the New Zealand Institute.[3] The specific epithet means "small eared".
This greenhood grows in damp, heavily shaded forest on southern parts of South Island of New Zealand and on Chatham, Stewart and Kapiti Islands.