''Daviesia debilior'' is a species of flowering plant in the family

Fabaceae Fabaceae () or Leguminosae,International Code of Nomen ...

and is

endemic Endemism is the state of a species being found only 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 foun ...

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 ...

of Western Australia. It is a shrub with low-lying stems and many erect branchlets, scattered linear to scale-like

phyllode Phyllodes are modified petiole (botany), petioles or leaf stems, which are leaf-like in appearance and function. In some plants, these become flattened and widened, while the leaf itself becomes reduced or vanishes altogether. Thus the phyllode co ...

s, and yellow, purplish, orange-pink and dark purplish flowers.

Description

''Daviesia debilior'' is a shrub with low-lying stems and many erect branchlets, and that typically grows up to high and wide. Its leaves are reduced to scattered, linear to scale-like phyllodes similar to the branchlets, up to long and wide. Juvenile phyllodes are narrowly spatula-shaped, long and wide. The flowers are arranged in groups of two to eight in leaf axils on a peduncle long, each flower on a thread-like

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 egg-shaped

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

s about long at the base. The

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 Etymology The term ''sepalum'' ...

s are long and joined at the base, forming a bell-shaped base, the two upper lobes joined for most of their length and the lower three triangular. The

standard Standard may refer to: Symbols * Colours, standards and guidons, kinds of military signs * Standard (emblem), a type of a large symbol or emblem used for identification Norms, conventions or requirements * Standard (metrology), an object ...

is broadly elliptic, long, wide and yellow with a purplish or red centre, the

wings A wing is a type of fin that produces both lift and drag while moving through air. Wings are defined by two shape characteristics, an airfoil section and a planform. Wing efficiency is expressed as lift-to-drag ratio, which compares the bene ...

long and pinkish-orange, and the

keel The keel is the bottom-most longitudinal structural element of a watercraft, important for stability. On some sailboats, it may have a fluid dynamics, hydrodynamic and counterbalancing purpose as well. The keel laying, laying of the keel is often ...

long and dark purplish-red. Flowering occurs from May to July and the fruit is a flattened, triangular pod long.

Taxonomy and naming

''Daviesia debilior'' was first formally described in 1982 by

Michael Crisp Michael Douglas Crisp (born 1950) is an emeritus professor in the Research School of Biology at the Australian National University located in Canberra. In 1976, he gained a PhD from the University of Adelaide, studying long-term vegetation chan ...

in the journal ''

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 specimens collected b
Charles Chapman
near Eneabba in 1977. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

(''debilior'') means "weaker" or "more feeble", in comparison to the closely related '' Daviesia hakeoides''. In the same journal, Crisp described two subspecies and the names are accepted by the

Australian Plant Census The Australian Plant Census (APC) provides an online interface to currently accepted, published, scientific names of the vascular flora of Australia, as one of the output interfaces of the national government Integrated Biodiversity Information Sys ...

: * ''Daviesia debilior'' Crisp subsp. ''debilior'' has gently upcurved branchlets and phyllodes, at least on the lower parts of the branchlets; * ''Daviesia debilior'' subsp. ''sinuans'' Crisp has weakly upcurved, sinuous branchlets and all phyllodes reduced to minute scales.

Distribution and habitat

This species of pea grows in heath between Eneabba,

Darlington Darlington is a market town in the Borough of Darlington, County Durham, England. It lies on the River Skerne, west of Middlesbrough and south of Durham. Darlington had a population of 107,800 at the 2021 Census, making it a "large town" ...

and

Wongan Hills Wongan Hills is a range of low flat-topped hills in the Avon Wheatbelt bioregion of Western Australia. It is located at , in the Shire of Wongan–Ballidu. History The range was first recorded in 1836 by Surveyor General of Western Australia Jo ...

in the

Avon Wheatbelt The Avon Wheatbelt is a bioregion in Western Australia. It has an area of . It is considered part of the larger Southwest Australia savanna ecoregion. Geography The Avon Wheatbelt bioregion is mostly a gently undulating landscape with low rel ...

Geraldton Sandplains Geraldton Sandplains is an Interim Biogeographic Regionalisation for Australia, interim Australian bioregion of Western Australia. It has an area of . The Geraldton Sandplains is part of the larger Southwest Australia savanna ecoregion, as asses ...

and

Jarrah Forest Jarrah Forest, also known as the Southwest Australia woodlands, is an interim Australian bioregion and ecoregion located in the south west of Western Australia.

biogeographic regions of south-western Western Australia. Subspecies ''sinuans'' has a more restricted distribution further inland than the

autonym Autonym may refer to: * Autonym, the name used by a person to refer to themselves or their language; see Exonym and endonym * Autonym (botany), an automatically created infrageneric or infraspecific name See also * Nominotypical subspecies, in zo ...

Conservation status

Subspecies ''debilior'' is classified as " Priority Two" by the Western Australian Government

Department of Biodiversity, Conservation and Attractions The Department of Biodiversity, Conservation and Attractions (DBCA) is the Government of Western Australia, Western Australian government department responsible for managing lands and waters described in the ''Conservation and Land Management A ...

, meaning that it is poorly known and from only one or a few locations, and subspecies ''sinuans'' " Priority Three" by the Government of Western Australia

, meaning that it is poorly known and known from only a few locations but is not under imminent threat.

References

{{Taxonbar, from1=Q15532035, from2=Q51054974, from3=Q51054986 debilior Eudicots of Western Australia Plants described in 1982 Taxa named by Michael Crisp