''Pterostylis subtilis'', commonly known as the thin mountain greenhood, is a species of
orchid endemic to
New South Wales. It has a
rosette of leaves and when flowering a single translucent white flower with dark green lines, a narrow, deeply notched
sinus between the
lateral sepals and a curved, protruding
labellum.
Description
''Pterostylis subtilis'' 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 a
rosette of fleshy leaves lying flat on the ground. Each leaf is long and wide. When flowering, there is a single white flower with dark green lines, long and wide which is borne on a flowering spike high. 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 to form 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 slightly longer than the petals and all sharply pointed. There is a narrow gap at each side of the flower between the petals and lateral sepals. The lateral sepals are erect with a tapering tip long and there is a deep, narrow sinus between them. The labellum is long, about wide, blunt and curved, protruding above the sinus. Flowering occurs in December and January.
Taxonomy and naming
''Pterostylis subtilis'' was first described in 2006 by
David Jones and the description was published in ''Australian Orchid Research'' from a specimen collected in the
Barrington Tops National Park
The Barrington Tops National Park is a protected national park located in the Hunter Valley in New South Wales, Australia. Gazetted in 1969, the park is situated between Scone, Singleton, Dungog, Gloucester and East Gresford.
The park is part ...
.
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 ...
(''subtilis'') is a
Latin word meaning "thin", "fine", "slender" or "acute ".
Distribution and habitat
The thin mountain greenhood grows with grasses on sheltered forest slopes in the Barrington Tops National Park.
References
{{Taxonbar, from=Q15492522
subtilis
Orchids of New South Wales
Plants described in 2006