''Pterostylis aquilonia'', commonly known as the northern cobra greenhood, is a species of

orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves, but the flowering plants lack a rosette and have a single flower with leaves on the flowering spike. This greenhood has a relatively large green, white and reddish-brown

self-pollinating Self-pollination is a form of pollination in which pollen from the same plant arrives at the stigma of a flower (in flowering plants) or at the ovule (in gymnosperms). There are two types of self-pollination: in autogamy, pollen is transferred to ...

flower.

Description

''Pterostylis aquilonia'' is a terrestrial,

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...

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 Tubers are a type of enlarged structure used as storage organs for nutrients in some plants. They are used for the plant's perennation (survival of the winter or dry months), to provide energy and nutrients for regrowth during the next growing ...

and when not flowering, a rosette of light green leaves long and wide. Flowering plants have a single flower long and wide borne on a spike high. The flowers are white, green, and reddish-brown. The

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal co ...

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

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 curves forward and ends with a short point. The

lateral Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction *Lateral cricoarytenoid muscle *Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral cons ...

sepals are erect with thread-like ends long with their tips bent forwards. The lateral sepals are held closely against the galea, and there is a broad, flat, platform-like

sinus Sinus may refer to: Anatomy * Sinus (anatomy), a sac or cavity in any organ or tissue ** Paranasal sinuses, air cavities in the cranial bones, especially those near the nose, including: *** Maxillary sinus, is the largest of the paranasal sinuses, ...

between their bases. The labellum is long, about wide and brown while slightly protruding above the sinus. Flowering occurs from May to June.

Taxonomy and naming

''Pterostylis aquilonia'' was first formally described in 1997 by David Jones and

Bruce Gray Bruce Gray (September 7, 1936 – December 13, 2017) was a Canadian actor, known for multiple roles in films and television shows for over 5 decades. Early Years Gray was born in Puerto Rico and lived in Toronto after 1949. He graduated from ...

. The description was published in ''The Orchadian'' from a specimen collected near

Herberton Herberton is a rural town and locality in the Tablelands Region, Queensland, Australia. In the , the locality of Herberton had a population of 855 people. Geography Herberton is on the Atherton Tableland in Far North Queensland. It is situa ...

. 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 ...

(''aquilonia'') is a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

word meaning "north" or "northern".

Distribution and habitat

The northern cobra greenhood grows in forest on the higher parts of the

Atherton Tableland The Atherton Tableland is a fertile plateau which is part of the Great Dividing Range in Queensland, Australia. The principal river flowing across the plateau is the Barron River. It was dammed to form an irrigation reservoir named Lake Tina ...

References

{{Taxonbar, from=Q15491359 aquilonia Endemic orchids of Australia Orchids of Queensland Plants described in 1997