''Rhizanthella slateri'', commonly known as the eastern underground orchid, is a species of flowering plant in the

orchid 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 floweri ...

family 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 else ...

to New South Wales. It is a mycoheterotrophic

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 medicina ...

that spends most of its life under the soil surface, its flowers only sometimes appearing a few millimetres about ground level.

Description

''Rhizanthella slateri'' is a leafless,

sympodial Sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, also referred to a ...

herb with a branching, whitish, underground stem up to long and about in diameter with prominent overlapping

bract In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or o ...

s. The stem is often branched with up to four flowering heads. The heads are up to in diameter and have up to thirty tube-shaped, purplish flowers surrounded by whitish, triangular floral bracts up to long. The

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

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 coine ...

is curved with a thread-like tip and has a broad base that forms a hood over the

column A column or pillar in architecture and structural engineering is a structural element that transmits, through compression (physical), compression, the weight of the structure above to other structural elements below. In other words, a column i ...

and the

lateral Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction * Lateral cricoarytenoid muscle * Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral co ...

sepals, sometimes protruding above the floral bracts. The petals are about half as long as the lateral sepals. The labellum is thick, tongue-like, heart-shaped and covered with fine, pimply papillae. The column is short and broad with narrow "wings". Flowering occurs in October and November with the heads maturing below the soil surface or up to above ground level.

Taxonomy and naming

The eastern underground orchid was first formally described in 1932 by

Herman Rupp Herman Montague Rucker Rupp (27 December 1872 – 2 September 1956) was an Australian clergyman and botanist who specialised in orchids. He was known throughout his life as Montague Rupp (pronounced "Rupe") and in later life as the "Orchid Man". R ...

and given the name ''Cryptanthemis slateri'' in ''

Proceedings of the Linnean Society of New South Wales The Linnean Society of New South Wales promotes ''the Cultivation and Study of the Science of Natural History in all its Branches'' and was founded in Sydney, New South Wales ( Australia) in 1874 and incorporated in 1884. History The Society su ...

'' from specimens collected near

Bulahdelah Bulahdelah is a town and locality in the Hunter/Mid North Coast region of New South Wales, Australia in the Mid-Coast Council local government area. At the 2016 census, the locality had a population of 1,424. The main population centre, wher ...

in 1931. In 1985, Mark Clements and Phillip Cribb changed the name to ''Rhizanthella slateri''. 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, bo ...

(''slateri'') honours Ernest William Slater who discovered the species.

Distribution and habitat

''Rhizanthella slateri'' grows in forest, usually under a deep layer of organic litter. It is known from populations in the Buladelah area, the Watagan Mountains, Blue Mountains,

Dharug National Park The Dharug National Park is a protected national park that is located in the Central Coast region of New South Wales, in eastern Australia. The national park is situated approximately north of the Sydney central business district and west o ...

and near

Nowra Nowra is a city in the South Coast region of New South Wales, Australia. It is located south-southwest of the state capital of Sydney (about as the crow flies). As of the 2021 census, Nowra has an estimated population of 22,584. Situated in t ...

, each population only known from a few individuals. Records from the

Lamington Plateau The Lamington National Park is a national park, lying on the Lamington Plateau of the McPherson Range on the Queensland/New South Wales border in Australia. From Southport on the Gold Coast the park is to the southwest and Brisbane is north. T ...

in Queensland are now recognised as '' R. omissa''.

Conservation status

This underground orchid is listed as "endangered" under the Australian Government ''

Environment Protection and Biodiversity Conservation Act 1999 The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cult ...

'' and as "vulnerable" under the New South Wales Government '' Biodiversity Conservation Act 2016''. The Bulahdelah population in the Great Lakes Local Government Area is listed as "endangered". That population was threatened by the building of a new highway, but a small diversion saved some individuals and some were able to be relocated.

References

External links

*
Documentation of discovery and photo of specimen
{{Taxonbar, from=Q2148150 slateri Orchids of New South Wales Endemic orchids of Australia Rare flora of Australia Plants described in 1932 Taxa named by Herman Rupp