Pterostylis lortensis, commonly known as the Lort River snail orchid, is a species of orchid endemic to the south-west of Western Australia. Non-flowering plants have a rosette of leaves flat on the ground but flowering plants usually lack a rosette and have a flowering stem with leaves and a single pale green and white flower with narrow, club-like lateral sepals.
Pterostylis lortensis is a terrestrial, perennial, deciduous, herb with an underground tuber. Non-flowering plants have a rosette of leaves NaNsigfig=1NaNsigfig=1 in diameter. Flowering plants lack a rosette but have a single pale green and white flower NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide on a flowering stem NaNsigfig=1NaNsigfig=1 high. There are between three and five leaves NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide on the flowering stem. The dorsal sepal and petals are fused, forming a hood or "galea" over the column, the dorsal sepal with a blunt tip. The lateral sepals are held close to the galea, almost close off the front of the flower and have erect, tips NaNsigfig=1NaNsigfig=1 long which have slightly-thickened, club-like tips. The labellum is relatively small but is not visible from outside the flower. Flowering occurs from August to September.[1]
Pterostylis lortensis was first formally described in 2014 by David Jones and Christopher French from a specimen collected near the Lort River and the description was published in Australian Orchid Review. The species had previously been known as Pterostylis sp. 'south coast clubbed sepals'.[2] The specific epithet (lortensis) refers to the Lort River where the type specimen was collected.
The Lort River snail orchid usually grows in winter-wet places, often amongst sedges. It occurs between Boxwood Hill and Israelite Bay in the Esperance Plains biogeographic region.
Pterostylis lortensis is listed as "not threatened" by the Government of Western Australia Department of Parks and Wildlife.