''Lambertia orbifolia'', commonly known as the roundleaf honeysuckle, is a shrub or small tree that 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 the

south-west The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

. It has more or less circular leaves and groups of between four and six orange-red flowers. Lambertia orbifolia fruit

Description

''Lambertia orbifolia'' is a shrub or small tree that grows to a height of up to but does not form a

lignotuber A lignotuber is a woody swelling of the root crown possessed by some plants as a protection against destruction of the plant stem, such as by fire. Other woody plants may develop basal burls as a similar survival strategy, often as a response t ...

. It has erect, spreading branches covered with soft hairs. The leaves are arranged in opposite pairs, sometimes in

whorls A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

of three and are in diameter and

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

. The flowers are arranged in groups of between four and six, each flower long with 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 of ...

s at the base. The flowers are orange-red and tube-shaped with hairs on the inside. Flowering occurs throughout the year but peaks between November and May. The fruit is a woody capsule in diameter with a short beak

Taxonomy and naming

''Lambertia orbifolia'' was first formally described in 1964 by Charles Gardner from a specimen collected at the

Scott River The Scott River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed March 9, 2011 river in Siskiyou County, California, United States. It is a tributary of the Klamath River, one of the ...

by Alfred John Gray in January 1945. The description was published in the ''

Journal of the Royal Society of Western Australia The Royal Society of Western Australia (RSWA) promotes science in Western Australia. The RSWA was founded in 1914. It publishes the ''Journal of the Royal Society of Western Australia'', and has awarded the Medal of the Royal Society of Western ...

''. 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 ...

(''orbifolia'') is from the

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 ...

words ''orbis'' meaning ''anything circular'' and ''-folius'' meaning "-leaved". Two subspecies have been named (''Lambertia orbifolia'' C.A.Gardner subsp. ''orbifolia'' ms and ''Lambertia orbifolia'' subsp. 'Scott River Plains' L.W.Sage 684) but not formally described.

Distribution and habitat

Roundleaf honeysuckle is known from two main areas, corresponding to the two proposed subspecies. Subspecies ''orbifolia'' occurs in the Narrikup area where it grows with

jarrah ''Eucalyptus marginata'', commonly known as jarrah, djarraly in Noongar language and historically as Swan River mahogany, is a plant in the myrtle family, Myrtaceae and is endemic to the south-west of Western Australia. It is a tree with roug ...

and marri in banksia woodland, and subspecies 'Scott River Plains' grows in dense shrubland and heathland in the Scott River Plains.

Ecology

''Lambertia orbifolia'' is killed by fire and regenerates from seed shortly after the fire, but few germinate in the interfire period. The species is susceptible to ''

Phytophthora cinnamomi ''Phytophthora cinnamomi'' is a soil-borne water mould that produces an infection which causes a condition in plants variously called "root rot", "dieback", or (in certain '' Castanea'' species), "ink disease". The plant pathogen is one of the wo ...

'' infection. The main pollinator of the species is thought to be the

New Holland honeyeater The New Holland honeyeater (''Phylidonyris novaehollandiae'') is a honeyeater species found throughout southern Australia. It was among the first birds to be scientifically described in Australia, and was initially named ''Certhia novaehollandi ...

(''Phylidonyris novaehollandiae'').

Conservation

Both proposed subspecies of this plant are listed as " Threatened Flora (Declared Rare Flora — Extant)" by the

Department of Environment and Conservation (Western Australia) The Department of Environment and Conservation (DEC) was a department of the Government of Western Australia that was responsible for implementing the state's conservation and environment legislation and regulations. It was formed on 1 July 2006 ...

and "critically endangered" under the Western Australian Government '' Biodiversity Conservation Act 2016''. An Interim Recovery Plan has been prepared for subspecies ''orbifolia''. Subspecies ''orbifolia'' is at a high risk of extinction due to ''P. cinnamomi'' infection and from damage caused by road maintenance activities. A proposal to translocate the subspecies has been prepared. The species 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 cultu ...

''. The main threats to the species are infection by ''P. cinnamomi'', road and track maintenance and changes in hydrology.

References

External links

{{Taxonbar, from=Q6481341 orbifolia Eudicots of Western Australia Plants described in 1964 Taxa named by Charles Gardner Endemic flora of Southwest Australia