''Caladenia amoena'', commonly known as charming 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,

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. It is a ground orchid which grows singly or in small groups, has a single dark green, hairy leaf and a single yellowish-green flower with red stripes. It is only known from a few sites and has been classified as Endangered.

Description

''Caladenia amoena'' 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, densely hairy, lance-shaped leaf, long and wide which often has purplish blotches near its base. A single flower (rarely two) is borne on a spike 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 to narrow lance-shaped, long and about wide. It is narrower near the end which terminates in a glandular structure about long. The lateral sepals are oblong to lance-shaped, long, about wide and end in a gland similar to the one on the dorsal sepal. 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 long and taper to a point. The labellum is heart-shaped, curves forward, long and wide when flattened. The labellum has three yellowish-green lobes, reddish in the central part, the middle lobe with about 7 pairs of broad teeth. The lateral lobes are also toothed near the mid-lobe. There are four rows of foot-shaped calli which are reddish and about at the back of the labellum, decreasing in size towards the front. 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 has reddish markings. Flowering occurs from August to October. ''Caladenia amoena'' is similar to '' C. concinna'' but has smaller flowers and somewhat drooping petals and sepals.

Taxonomy and naming

''Caladenia amoena'' was first formally described by David L. Jones in 1994 and the description was published in '' Muelleria''. 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 ...

(''amoena'') 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 "pleasant" or "delightful".

Distribution and habitat

Charming spider orchid is only known from two sites, growing in grassy

box–ironbark forest Box–ironbark forest is a forest or woodland ecosystem that is largely limited to central Victoria in south-eastern Australia. Because its component tree species produce abundant nectar and pollen throughout the year, it is important for the c ...

in south-central Victoria, on the northern outskirts of

Melbourne Melbourne ( ; Boonwurrung/Woiwurrung: ''Narrm'' or ''Naarm'') is the capital and most populous city of the Australian state of Victoria, and the second-most populous city in both Australia and Oceania. Its name generally refers to a met ...

Conservation

Only 45 ''Caladenia amoena'' plants were known in 2000 and the species is classified as "Endangered" by the Victorian government. It is also classed as "Endangered" (EN) under the Australian Government Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and a recovery plan has been prepared.

References

{{Taxonbar, from=Q15287444 amoena Plants described in 1994 Endemic orchids of Australia Orchids of Victoria (state) Taxa named by David L. Jones (botanist)