''Caladenia aestiva'', commonly known as summer 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 south-eastern Australia. It is a ground orchid which grows singly or in small groups in the

Australian Capital Territory The Australian Capital Territory (commonly abbreviated as ACT), known as the Federal Capital Territory (FCT) until 1938, is a landlocked federal territory of Australia containing the national capital Canberra and some surrounding townships. ...

and Victoria. It has one or two greenish-yellow to pale yellow flowers, often while the single, hairy leaf withers.

Description

''Caladenia aestiva'' 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, sparsely hairy, linear to narrow lance-shaped leaf, long and wide. The leaf is dull green and reddish near the base and often is withered by the time the flower opens. One or two flowers are borne on a spike up to high. 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, linear in shape, long, about wide but abruptly narrowing about half-way towards the tip. The lateral sepals are long, about wide and 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 somewhat shorter and narrower. The petals and sepals narrow abruptly at about their midpoint, linear nearer their bases then thread-like towards the ends. The labellum is linear to egg-shaped when flattened, about long and wide, pale yellow or greenish-yellow, maroon in the central part. There are many short, tooth-like calli along the edges of the labellum and four to six rows of greenish to reddish calli in the centre. 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. ...

is long and greenish-yellow, sometimes with a few red marks, and has broad wings. Flowering occurs from December to January and is often stimulated by bushfire. This species has been confused with '' Caladenia pallida'' since 1840, but has much larger flowers with somewhat more stiffly-held petals and sepals than ''C. pallida''.

Taxonomy and naming

''Caladenia aestiva'' was first formally described by David 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 near the road between Benambra and Wulgulmerang. 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 ...

(''aestiva'') 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 "summer", in reference to the flowering season of this species.

Distribution and habitat

Summer spider orchid is widespread in north-eastern Victoria, growing in sheltered, grassy areas in high-altitude woodlands. In the Australian Capital Territory it is confined to the Brindabella Range.

References

External links

* {{Taxonbar, from=Q15287428 aestiva Plants described in 1991 Endemic orchids of Australia Orchids of the Australian Capital Territory Orchids of Victoria (state) Taxa named by David L. Jones (botanist)