''Pterostylis pyramidalis'', commonly known as the tall snail orchid or leafy snail orchid is a species of orchid which is endemic to the

south-west The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

of Western Australia. As suggested by one of its common names, it can be distinguished from other snail orchids by its height of up to .

Description

''Pterostylis pyramidalis'' has 3 or 4 leaves bunched near the base and 6 or 7 scattered up the flower stalk, with those near the base having a petiole (stalk) and those further up sessile (stalkless). The leaves are long and . The flower stem is tall, tall and smooth. The flowers appear from August to October and are green and white, . Flowering is stimulated by summer fires.

Taxonomy and naming

''Pterostylis pyramidalis'' was first formally described by

John Lindley John Lindley FRS (5 February 1799 – 1 November 1865) was an English botanist, gardener and orchidologist. Early years Born in Catton, near Norwich, England, John Lindley was one of four children of George and Mary Lindley. George Lindley w ...

A Sketch of the Vegetation of the Swan River Colony "A Sketch of the Vegetation of the Swan River Colony", also known by its standard botanical abbreviation ''Sketch Veg. Swan R.'', is an 1839 article by John Lindley on the flora of the Swan River Colony. Nearly 300 new species were published in it, ...

in 1840. The genus ''Pterostylis'' has been reviewed by David Jones and Mark Clements who changed the name from ''P. pyramidalis'' to ''Linguella pyramidalis'' but the new name has not been widely accepted, including by the Western Australian Herbarium. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

(''pyramidalis'') is a Latin word meaning "pyramid-shaped".

Distribution and habitat

The tall snail orchid grows on grey-black peaty sand on the margins of swamps. It sometimes forms large colonies often with the flowers partly submerged. It occurs in the Avon Wheatbelt, Esperance Plains, Jarrah Forest, Mallee,

Swan Coastal Plain The Swan Coastal Plain in Western Australia is the geographic feature which contains the Swan River as it travels west to the Indian Ocean. The coastal plain continues well beyond the boundaries of the Swan River and its tributaries, as a geol ...

and

Warren A warren is a network of wild rodent or lagomorph, typically rabbit burrows. Domestic warrens are artificial, enclosed establishment of animal husbandry dedicated to the raising of rabbits for meat and fur. The term evolved from the medieval Angl ...

biogeographic regions A biogeographic realm or ecozone is the broadest biogeographic division of Earth's land surface, based on distributional patterns of terrestrial organisms. They are subdivided into bioregions, which are further subdivided into ecoregions. De ...

of Western Australia.

Conservation status

This species is classified as "not threatened" by the

Government of Western Australia The Government of Western Australia, formally referred to as His Majesty's Government of Western Australia, is the Australian state democratic administrative authority of Western Australia. It is also commonly referred to as the WA Government o ...

Department of Parks and Wildlife The Department of Parks and Wildlife (DPaW) was the department of the Government of Western Australia responsible for managing lands described in the ''Conservation and Land Management Act 1984'' and implementing the state's conservation and e ...

References

{{Taxonbar, from=Q15491648 pyramidalis Endemic orchids of Australia Orchids of Western Australia Plants described in 1840 Endemic flora of Western Australia