''Boronia exilis'' is a plant in the citrus

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Rutaceae The Rutaceae is a family, commonly known as the rueRUTACEAE
in BoDD – Botanical Derm ...

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 a small area in 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 is a slender, erect

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 ...

with well-spaced,

simple Simple or SIMPLE may refer to: *Simplicity, the state or quality of being simple Arts and entertainment * ''Simple'' (album), by Andy Yorke, 2008, and its title track * "Simple" (Florida Georgia Line song), 2018 * "Simple", a song by Johnn ...

, more or less cylindrical leaves and pink, four-

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 ...

led flowers in groups of between three and nine on the ends of the branches.

Description

''Boronia exilis'' is an erect perennial with slender stems that grows to a height of about and has many slender,

glabrous Glabrousness (from the Latin ''glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part of ...

branches. The leaves are simple, more or less cylindrical long and fall off early so that there are few leaves on the lower part of the stems. The flowers are pink and are borne in groups of between three and nine, each on a

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

long with hairy bracts at the base that fall off as the flower develops. The four

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 ...

s are dark red, hairy on both sides and about long. The four

s are pink, oblong to elliptic and about long and the eight

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s are hairy.

Taxonomy and naming

''Boronia exilis'' was first formally described in 1998 by

Paul G. Wilson Paul Graham Wilson (born 1928) is an Australian botanist. He has been a most prolific contributor to the journal ''Nuytsia (journal), Nuytsia'', contributing to the first issue in 1970 and to the 12th volume in 1998, which was dedicated to him f ...

and the description was published in ''

Nuytsia ''Nuytsia floribunda'' is a hemiparasitic tree found in Western Australia. The species is known locally as moodjar and, more recently, the Christmas tree or Western Australian Christmas tree. The display of intensely bright flowers during the ...

'' from a specimen collected in the

Scott National Park Scott National Park is a national park in the South West (Western Australia), South West region of Western Australia, south of Perth. It is based on the catchment area of the Scott River (Western Australia), Scott River and the eastern bank of ...

. 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 ...

(''exilis'') 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 "thin" or "slender". referring to the stems of this boronia.

Distribution and habitat

This boronia grows is only known from 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 ...

area where it grows in seasonally wet heath.

Conservation

''Boronia exilis'' is classified 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 ...

'' and 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 ...

. An interim recovery plan has been prepared. The main threats to the species include inappropriate fire regimes, disease caused by ''

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 ...

'' and road maintenance activities.

References

{{Taxonbar, from=Q15388849 exilis Flora of Western Australia Plants described in 1998 Taxa named by Paul Graham Wilson Endemic flora of Southwest Australia