''Pterostylis viriosa'', commonly known as the Adelaide Hills banded greenhood, is a plant in the orchid family

Orchidaceae 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 ...

and is

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 ...

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

. Flowering plants have up several green flowers with faint white stripes. The flowers have an insect-like labellum which is green with a dark green mound on its upper end. Non-flowering plants have a rosette of leaves on a stalk, but flowering plants lack the rosette, instead having several stem leaves.

Description

''Pterostylis viriosa'', 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. Non-flowering plants have a rosette of leaves on a short stalk. Flowering plants have up to several green flowers with faint white stripes on a flowering spike up to high. The flowering spike lacks a rosett but has a small number of stem leaves. 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 petals have a wide, transparent flange on their outer edges. 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 turn downwards and are joined for most of their length before tapering to triangular tips. The labellum is insect-like and hairy with a dark green mound on the "head" end and a dark green mid-line. Flowering occurs from late July to early September.

Taxonomy and naming

This greenhood was first formally described in 2006 by David Jones and given the name ''Bunochilus viriosus''. The description was published in ''Australian Orchid Research'' from a specimen collected in the

Belair National Park Belair National Park (formerly known as the National Park and as Belair Recreation Park) is a protected area in Belair, South Australia, southeast of Adelaide city centre; it covers an area of . It was proclaimed in 1891 and was the first nation ...

. In 2008 Robert Bates changed the name to ''Pterostylis viriosa''. 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 ...

(''viriosa'') 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 "robust" or "strong", referring to the robust nature of this orchid and to its large flowers.

Distribution

The Adelaide Hills banded greenhood occurs in the Fleurieu (KAN02),

Mount Lofty Ranges The Mount Lofty Ranges are a range of mountains in the Australian state of South Australia which for a small part of its length borders the east of Adelaide. The part of the range in the vicinity of Adelaide is called the Adelaide Hills and ...

(FLB01), Central Flinders (FLB06) and Talia (EYB04)

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 South Australia.

References

{{Taxonbar, from=Q15492203 viriosa Endemic orchids of Australia Orchids of South Australia Plants described in 2006