''Diuris micrantha'', commonly called the dwarf bee orchid or tiny bee orchid, is a rare 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 ...

which 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 ...

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 ...

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

. It has four to six linear leaves at its base and up to six yellow flowers with reddish brown markings. It grows in swampy places south of

Perth Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth is ...

Description

''Diuris micrantha'' is a

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 ...

ous,

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 between four and six linear leaves, each leaf long and wide in a loose tuft at the base. Up to six yellow flowers with reddish brown markings, about long and wide are borne on a flowering stem tall. The dorsal sepal curves upwards and is narrow egg-shaped, long and about wide. The lateral sepals are linear, green and purplish, long, about wide, turned downwards and parallel to each other. 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 are more or less erect, spread apart from each other with a broadly egg-shaped to almost round blade long and wide on a reddish-brown stalk long. There is a distinct reddish brown blotch near the tip of the petals. The labellum is long and has three lobes. The centre lobe is egg-shaped to wedge-shaped, wide and the side lobes are linear to egg-shaped, long and about wide. There are two parallel, reddish brown, ridge-like calli about long near the mid-line of the base of the labellum. Flowering occurs in September and October.

Taxonomy and naming

''Diuris micrantha'' was first formally described in 1991 by David Jones from a specimen collected in Mandogalup, and the description was published in ''Australian Orchid Review''. 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 ...

(''micrantha'') is derived from the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

words ''mikros'' meaning "small" or "little" and ''anthos'' meaning "flower", referring to the small flowers of this orchid.

Distribution and habitat

The dwarf bee orchid grows with dense sedges in swampy place between Perth and Boyup Brook in the

Jarrah Forest Jarrah forest is tall open forest in which the dominant overstory tree is ''Eucalyptus marginata'' (jarrah). The ecosystem occurs only in the Southwest Botanical Province of Western Australia. It is most common in the biogeographic region named in ...

and

Swan Coastal Plain The Swan Coastal Plain in Western Australia is the geographic feature which contains the Swan River as it travels west to the Indian Ocean. The coastal plain continues well beyond the boundaries of the Swan River and its tributaries, as a geol ...

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

''Diuris micrantha'' is classified as "vulnerable" under the Australian Government '' Environment Protection and Biodiversity Conservation Act 1999'' and as " Threatened Flora (Declared Rare Flora — Extant)" by the Department of Environment and Conservation (Western Australia). It is threatened by weeds and by inappropriate fire regimes, especially by fires in winter and spring.

References

{{Taxonbar, from=Q10267401 micrantha Endemic orchids of Australia Orchids of Western Australia Endemic flora of Western Australia Plants described in 1991