''Pterostylis erubescens'', commonly known as the red sepaled 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 lack a rosette and have a single large green flower which turns reddish-brown as it ages, and has leaves on the flowering spike.

Description

''Pterostylis erubescens'' is a terrestrial, perennial, deciduous,

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

with an underground tuber and when not flowering, a rosette of leaves in diameter. Flowering plants have a single green flower long and wide on a flowering stem high. The flowers turn reddish-brown as they age. There are up to ten leaves long and wide on the flowering stem. The dorsal sepal and

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

s are fused, forming a hood or "galea" over the

column A column or pillar in architecture and structural engineering is a structural element that transmits, through compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. ...

, the dorsal sepal with a tapered tip and the petals broadly flared. The lateral sepals are held close to the galea, almost close off the front of the flower and have erect, thread-like tips long. The labellum is relatively large but not visible from outside the flower. Flowering occurs from late July to September.

Taxonomy and naming

''Pterostylis erubescens'' was first formally described in 2014 by David Jones and

Christopher French Christopher French could refer to: *Christopher French (theologian) (fl. c. 1650–c.1713), Irish professor of divinity *Chris French (Christopher Charles French) (born 1956), British psychologist *Christopher French (judge) (1925–2003), British ...

from a specimen collected near Augusta and the description was published in ''Australian Orchid Review''. The species had previously been known as ''Pterostylis'' sp. 'red flowered'. 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 ...

(''erubescens'') is a Latin word meaning "reddening" referring to the colour of the upper parts of the flowers of this species.

Distribution and habitat

The red sepaled snail orchid grows in forest, woodland and around granite outcrops between Mandurah and Albany in the Esperance Plains, Jarrah Forest,

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

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 ...

Conservation

''Pterostylis erubescens'' is listed 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 en ...

References

{{Taxonbar, from=Q29650683 erubescens Endemic orchids of Australia Orchids of Western Australia Plants described in 2014