''Caladenia coactilis'', commonly known as thick fingers, is a plant in the orchid family

Orchidaceae 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 ...

and 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 ...

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

. It is a ground orchid which grows singly or in loose groups and has a single hairy leaf and one or two flowers which are bright pink inside and brownish on the back.

Description

''Caladenia coactilis'' is a terrestrial,

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 ...

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...

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 grows singly or in loose groups. It has a single, erect, densely hairy, linear to lance-shaped leaf, long and wide. One or two flowers are borne on a spike tall. The flowers are bright pink inside and brownish on the outside due to a dense covering of

glands In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure De ...

and are about in diameter. 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 ...

is erect, long, wide, linear to lance-shaped or egg-shaped and curves forward. 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 long, wide, lance-shaped, slightly curved, held horizontally and spread widely. The sepals and petals are glabrous on the inside and densely covered with brownish glands on their backs. The labellum is broadly egg-shaped when flattened and bright pink with many narrow, dark red lines. It has three

lobe Lobe may refer to: People with the name * Lobe (surname) Science and healthcare * Lobe (anatomy) * Lobe, a large-scale structure of a radio galaxy * Glacial lobe, a lobe-shaped glacier * Lobation, a characteristic of the nucleus of certain biolo ...

s with the lateral lobes erect and surrounding 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. ...

and with three pairs of linear teeth pointing forward on their edges. The central lobe of the labellum curves forward, with between two and four rows of bright yellow calli and has a yellow tip. Flowering occurs from August to September.

Taxonomy and naming

''Caladenia coactilis'' was first formally described by David L. Jones in 1991 and the description was published in ''Australian Orchid Research''. 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 in the

Telowie Gorge Conservation Park Telowie Gorge Conservation Park, formerly Telowie Gorge National Park, was a protected area located in the Australian state of South Australia to the east of the town of Port Germein, South Australia, Port Germein in the gazetted locality of Telo ...

. 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 ...

(coactilis) is a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

word meaning "made thick", referring to the thickness of many of the organs of this orchid.

Distribution and habitat

This caladenia usually grows in open forest and is found in the southern Flinders Ranges and northern

Mount Lofty Ranges The Mount Lofty Ranges are a range of mountains in the Australian state of South Australia which for a small part of its length borders the east of Adelaide. The part of the range in the vicinity of Adelaide is called the Adelaide Hills and ...

References

{{Taxonbar, from=Q9673454 coactilis Plants described in 1991 Endemic orchids of Australia Orchids of South Australia Taxa named by David L. Jones (botanist)