''Caladenia busselliana'', commonly known as Bussell's spider orchid, is a plant in the orchid family Orchidaceae and is endemic to a small area in 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 is a rare orchid with an erect, hairy leaf and up to three pale yellow flowers. Caladenia busselliana 01

Description

''Caladenia busselliana'' is a terrestrial, perennial, deciduous,

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 and a single erect, hairy leaf long and wide. There are up to three pale yellow flowers on a stem high. The flowers are long and wide. The 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 spread widely and the sepals are thickened. The labellum is pale yellow to white and lacks the red tip common to similar spider orchids. The sides of the labellum have narrow teeth or calli which have a "clubbed" end. There are four or more rows of red-tipped calli along the centre of the labellum. Flowering occurs between September and October and is followed by a non-fleshy,

dehiscent Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part; structures that op ...

capsule containing a large number of seeds.

Taxonomy and naming

''Caladenia busselliana'' was first formally described 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 in 2001 from a specimen collected by Greg Bussell near Quindalup and the description was published in '' Nuytsia''. 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 ...

(''busselliana'') honours the collector of the type specimen.

Distribution and habitat

Bussell's spider orchid grows in swampy

jarrah ''Eucalyptus marginata'', commonly known as jarrah, djarraly in Noongar language and historically as Swan River mahogany, is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a tree with roug ...

forest and marri woodland, often with green kangaroo paw, (''

Anigozanthos viridis ''Anigozanthos viridis'', commonly known as Green Kangaroo Paw, is a grass-like perennial herb native to south western coastal regions of Western Australia. The Noongar peoples know the plant as Koroylbardany. Description The rhizomatous plant t ...

'') and the more common swamp spider orchid (''

Caladenia paludosa ''Caladenia paludosa'', commonly known as the swamp spider orchid, is a species of orchid endemic to the south-west of Western Australia. It has a single erect, hairy leaf and up to three red, greenish-yellow and cream-coloured flowers. It most ...

''). It is only known from two small areas near Vasse and

Yallingup Yallingup is a town in the South West region of Western Australia, south of Perth. Yallingup is a popular tourist destination because of its beaches and limestone caves, and proximity to Leeuwin-Naturaliste National Park. History and industry Y ...

at the northern end of the

Leeuwin-Naturaliste ridge Leeuwin-Naturaliste National Park is a national park in the South West region of Western Australia, south of Perth. It is named after the two locations at either end of the park which have lighthouses, Cape Leeuwin and Cape Naturaliste. It is ...

in the

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 region An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...

Conservation

''Caladenia busselliana'' is classified as "endangered" under the Australian Government Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and as "rare flora" under the Western Australian '' Wildlife Conservation Act 1950''. Only about fifty specimens are known and there is a continuing decline in the quality of habitat and number of mature individuals.

References

{{Taxonbar, from=Q9673390 brownii Endemic orchids of Australia Orchids of Western Australia Plants described in 2001 Taxa named by Stephen Hopper Taxa named by Andrew Phillip Brown