''Caladenia australis'', commonly known as southern spider orchid, 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 ...

to Victoria, although it was also found on one

Bass Strait Bass Strait () is a strait separating the island state of Tasmania from the Australian mainland (more specifically the coast of Victoria, with the exception of the land border across Boundary Islet). The strait provides the most direct waterwa ...

island on one occasion in 1968. It has a single hairy leaf and usually only one creamy-yellow flower with red streaks, the flower on a hairy stalk.

Description

''Caladenia australis'' 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 a single hairy leaf, long and wide. There is usually only a single flower on a thin, wiry, sparsely hairy spike high, each flower wide. 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 ...

curves forward or droops over the rest of the flower. All three sepals are long, wide and taper to a thin end with dark red, club-like

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 ...

. 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 a similar size and shape to the sepals but lack glandular ends. The petal and sepals spread widely, sometimes drooping near their ends and are a creamy-yellow colour, often with red streaks. The labellum is shiny, yellowish with a maroon tip and curves forward, with the tip rolled under at the end. It is egg-shaped, long and about wide. The edges of the labellum have many teeth up to long and there are 4 to 6 rows of dark red calli along the labellum mid-line, decreasing in size towards the front. Flowering occurs between September and November and is strongly enhanced by fires the previous summer.

Taxonomy and naming

The species was first formally described by

Geoffrey Carr Geoffrey Carr (22 January 1886 – 13 July 1969) was a Great Britain, British rowing Coxswain (rowing), coxswain who competed in the 1912 Summer Olympics. Carr was born in Putney and became a member of Thames Rowing Club. He was the coxswain ...

in 1991 and the description was published in ''Indigenous Flora and Fauna Association Miscellaneous Paper 1''. 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 on

Wilsons Promontory Wilsons Promontory, is a peninsula that forms the southernmost part of the Australian mainland, located in the state of Victoria. South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia. Located at nearb ...

. 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 ...

(''australis'') 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 "southern".

Distribution and habitat

''Caladenia australis'' mostly grows in near-coastal areas of Victoria and although widespread, is also uncommon. It grows in heath and woodland, usually on sandy soil. There is a single record from the southern part of Flinders Island in 1968.

Conservation

There are insufficient data to make an assessment of the conservation status of southern spider orchid in Victoria but it is listed as "Endangered" under the Tasmanian "

Threatened Species Protection Act 1995 The ''Threatened Species Protection Act 1995'' (TSP Act), is an act of the Parliament of Tasmania that provides the statute relating to conservation of flora and fauna. Its long title is An Act to provide for the protection and management of th ...

References

{{Taxonbar, from=Q15287489 australis Plants described in 1991 Endemic orchids of Australia Orchids of Victoria (state) Taxa named by Geoffrey William Carr