''Caleana triens'', commonly known as broad-billed duck orchid is a species of orchid endemic to the

south-west The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

of Western Australia. It has a single smooth leaf and is distinguished by its flattened labellum with calli only near its tip and by its relatively early flowering period.

Description

''Caleana triens'' has a single smooth, dull green or dull red leaf, long and wide. Usually only one greenish yellow and red flower, long and wide is borne on a thin, wiry stalk high. The dorsal sepal, lateral sepals 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 narrow and hang downwards with the dorsal sepal pressed against the column which has broad wings, forming a bucket-like shape. The labellum is flattened and only about one-third of the outer part of the labellum is covered with glossy black glands or calli. Flowering occurs in September and October.

Taxonomy and naming

The broad-billed duck orchid was first formally described in 2006 by

Stephen Hopper Stephen Donald Hopper AC FLS FTSE (born 18 June 1951) is a Western Australian botanist. He graduated in Biology, specialising in conservation biology and vascular plants. Hopper has written eight books, and has over 200 publications to his n ...

and Andrew Brown who gave it the name ''Paracaleana triens''. The

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * Ty ...

specimen was collected near York and description was published in '' Australian Systematic Botany''. In 2014, based on molecular studies, Joseph Miller and Mark Clements transferred all the species previously in ''Paracaleana'' to ''Caleana'', so that the present species became ''Caleana triens''. 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 ...

(''triens'') is a Latin word meaning "third", referring to there being calli only one-third of the outer part of the labellum.

Distribution and habitat

''Caleana triens'' grows in forest, woodland or shrubland in sandy soil between York and Esperance in the Avon Wheatbelt, Jarrah Forest and Mallee

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

''Caleana triens'' (as ''Paracaleana triens'') is classified as "not threatened" by the Western Australian Government

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 e ...

References

{{Taxonbar, from1=Q42705435

triens The triens (plural trientes) was an Ancient Roman bronze coin produced during the Roman Republic valued at one-third of an as (4 unciae). The most common design for the triens featured the bust of Minerva and four pellets (indicating four unci ...

Orchids of Western Australia Endemic orchids of Australia Plants described in 2006 Endemic flora of Southwest Australia