''Daviesia megacalyx'' is a species of flowering plant in the 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 elsew ...
to a restricted part of the south-west of Western Australia. It is an erect,
glabrous shrub with scattered, leathery, elliptic
phyllode
Phyllodes are modified 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 comes to serve the ...
s and apricot-coloured and deep pink flowers.
Description
''Daviesia megacalyx'' is an erect, glabrous shrub that typically grows to a height of . Its phyllodes are scattered, elliptic to narrowly egg-shaped with the narrower end towards the base, long, wide and leathery. The flowers are arranged in groups of one or two in leaf axils on a
peduncle long, the
rachis up to long, each flower 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. 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 The term ''sepalum'' was coined b ...
s are long and joined at the base, the lobes more or less similar, triangular and about long. The
standard petal is broadly egg-shaped, about long and apricot with a maroon base and intensely yellow centre. The
wings are about long and deep pink, and the
keel
The keel is the bottom-most longitudinal structural element on a vessel. On some sailboats, it may have a hydrodynamic and counterbalancing purpose, as well. As the laying down of the keel is the initial step in the construction of a ship, in Br ...
about long and deep pink. Flowering occurs in August and September and the fruit is a flattened, leathery triangular
pod
Pod or POD may refer to:
Biology
* Pod (fruit), a type of fruit of a flowering plant
* Husk or pod of a legume
* Pod of whales or other marine mammals
* "-pod", a suffix meaning "foot" used in taxonomy
Electronics and computing
* Proper ort ...
long.
Taxonomy and naming
''Daviesia megacalyx'' was first formally described in 1995 by
Michael Crisp in ''
Australian Systematic Botany'' from specimens collected near
Ravensthorpe in 1979.
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 ...
(''megacalyx'') means "large
calyx", referring to the sepals.
Distribution and habitat
This daviesia grows in
mallee-heath and dense shrubland near Ravensthorpe in the
Esperance Plains
Esperance Plains, also known as Eyre Botanical District, is a biogeographic region in southern Western Australia on the south coast between the Avon Wheatbelt and Hampton bioregions, and bordered to the north by the Mallee region. It is a pl ...
biogeographic region of south-western Western Australia.
Conservation status
''Daviesia megacalyx'' is listed as "endangered" under the Australian Government ''
Environment Protection and Biodiversity Conservation Act 1999'' and as "
Threatened Flora (Declared Rare Flora — Extant)" by the
Department of Biodiversity, Conservation and Attractions
The Department of Biodiversity, Conservation and Attractions (DBCA) is the Western Australian government
The Government of Western Australia, formally referred to as His Majesty's Government of Western Australia, is the Australian state de ...
. The main threats to the species include inappropriate fire regimes, habitat loss and degradation by mining activities and dieback caused by ''
Phytophthora''.
References
{{Taxonbar, from=Q27828440
megacalyx
Eudicots of Western Australia
Plants described in 1995
Taxa named by Michael Crisp