''Caladenia bicalliata'' subsp. ''cleistogama'', commonly known as the shy limestone spider orchid or sandhill spider orchid, is a plant in the orchid family Orchidaceae and is

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

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 erect, hairy leaf and one or two cream-coloured flowers which are smaller than those in subspecies ''bacalliata'' .

Description

''Caladenia bicalliata'' subsp. ''cleistogama'' 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 which occurs singly or in small clumps. It has a single erect, very hairy, linear to lance-shaped leaf, long and wide. The inflorescence is a

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

, high with one or two flowers, each flower about long and wide. The dorsal sepal abruptly narrows about one-third of its length from the base. 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 are much shorter than those of subspecies ''bicalliata'', lack reddish-brown tips and are a paler greenish-cream colour. The labellum is white with red spots and a serrated edge and has two rows of white-tipped calli along its centre. Flowering occurs from August to early September, however the flowers only rarely open fully.

Taxonomy and naming

'' Caladenia bicalliata'' was first formally described by

Richard Rogers Richard George Rogers, Baron Rogers of Riverside (23 July 1933 – 18 December 2021) was a British architect noted for his modernist and Functionalism (architecture), functionalist designs in high-tech architecture. He was a senior partner a ...

in 1909. In 2001

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 described two subspecies, including subspecies ''cleistogama'' and the description of the two subspecies 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 ...

(''cleistogama'') is from the Latin ''cleistogamus'' (fertilised within the unopened flower), referring to the self-pollinating habit of this subspecies.

Distribution and habitat

Shy limestone spider orchid occurs in a narrow coastal strip, growing on consolidated sand dunes between

William Bay National Park William Bay National Park is a national park in the Great Southern region of Western Australia, southeast of Perth and between the towns of Denmark and Walpole. Description Situated approximately west of Denmark, William Bay National Park ...

and

Cape Arid National Park Cape Arid National Park is a List of national parks of Australia, national park located in Western Australia, southeast of Perth. The park is situated east of Esperance, Western Australia, Esperance and lies on the shore of the South coast of W ...

in the Esperance Plains and

Warren A warren is a network of wild rodent or lagomorph, typically rabbit burrows. Domestic warrens are artificial, enclosed establishment of animal husbandry dedicated to the raising of rabbits for meat and fur. The term evolved from the medieval Angl ...

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

''Caladenia bicalliata'' subsp. ''cleistogama'' 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, from=Q26238620 bicalliata Endemic orchids of Australia Orchids of South Australia Orchids of Western Australia Plants described in 2001 Taxa named by Stephen Hopper Taxa named by Andrew Phillip Brown