''Corybas obscurus'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of terrestrial

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 ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. It has a solitary heart-shaped leaf and a deep crimson or nearly black flower and is part of the '' Corybas trilobus''

aggregate Aggregate or aggregates may refer to: Computing and mathematics * collection of objects that are bound together by a root entity, otherwise known as an aggregate root. The aggregate root guarantees the consistency of changes being made within the ...

Description

''Corybas obscurus'' is a

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

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 ...

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 a single reniform (kidney-shaped) or cordiform (heart-shaped) leaf born on a petiole that is 5.1–40.8 mm long. The leaf itself is 5.8–18.2 × 9.6–26.7 mm and has a

mucronate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

apex. The single flower is held on a peduncle with a small floral bract. The dorsal

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 ...

arches over the labellum and is broad at the apex; it ranges from dark crimson to nearly black. The lateral sepals range from crimson to dark red and are filiform (thread-like), between 11.7 and 20.6 mm long. The

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 resemble the lateral sepals but are longer, between 27.3 and 57.2 mm long. The labellum, around 10 mm wide, is auriculate at the base and is strongly curved downwards. It folds inwards and forms a central groove; its margins are very slightly cupped. The inner surface of the labellum is covered with

trichome Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a pla ...

s ending with a compact head (glandular). It is curved at its base, forming a cylindrical opening with a with a flared, highly fimbriate (toothed) mouth. The surface of the posterior half of the labellum has many hair-like structures that are curved backwards. The labellum is dark crimson or nearly black with a pale green center. The ovary is 3.0–8.4 mm long. 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. ...

is 1.6 mm long and curved, and the stigma is flanked with two notched winglike structures. Flowering occurs from October to November. When not in flower, ''Corybas obscurus'' can be confused with other species in the ''C. trilobus'' species complex, whose members all share auriculate leaves. In flower, it is similar to '' Corybas confusus'', particularly in terms of the lip color. However, ''C. obscurus'' has a short dorsal sepal firmly pressed against the upper border of the labellum and a reniform to cordiform leaf. ''C. obscurus'' may be distinguished from ''C. trilobus'' by its dark flower coloration and opacity.

Taxonomy

''Corybas obscurus'' was first formally described in 2016 by

Carlos Adolfo Lehnebach Carlos Adolfo Lehnebach is a New Zealand botanist. He is employed as a botany curator at the Museum of New Zealand Te Papa Tongarewa. Lehnebach studies New Zealand orchids. As of January 2018, he has described seven new species of orchid and two s ...

. Its

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 ...

is a Latin word that means "hidden" or "concealed" and refers to the dark color of the flower.

Distribution and habitat

''Corybas obscurus'' occurs in southern beech forest in association with ''

Nothofagus ''Nothofagus'', also known as the southern beeches, is a genus of 43 species of trees and shrubs native to the Southern Hemisphere in southern South America (Chile, Argentina) and Australasia (east and southeast Australia, New Zealand, New Gui ...

'' or in forests or shrubland with ''

Kunzea ''Kunzea'' is a genus of plants in the family Myrtaceae and is endemic to Australasia. They are shrubs, sometimes small trees and usually have small, crowded, rather aromatic leaves. The flowers are similar to those of plants in the genus '' Lep ...

'' and ''

Leptospermum ''Leptospermum'' is a genus of shrubs and small trees in the myrtle family Myrtaceae commonly known as tea trees, although this name is sometimes also used for some species of ''Melaleuca''. Most species are endemic to Australia, with the greate ...

''. It grows in leaf litter. It has been found at elevations from 600 to 1000 m. ''C. obscurus'' was first described from the

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...

but is known from the

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...

as well.

References

{{Taxonbar, from=Q42734617 obscurus Endemic orchids of New Zealand