''Ornduffia calthifolia'', also known as mountain villarsia, is a species of plant in the Menyanthaceae

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 ...

of wetland plants 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 ...

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 ...

Description

The species grows as an erect, many-branched, semi-succulent,

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 ...

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 medicinal ...

to a height of about 40& cm when not in flower and to 75 cm when flowering. The fleshy leaves are round with toothed edges and shaped as shallow cups. The yellow flowers are 1 cm long, with 5

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 ...

s and 5 broad

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. The seed capsules s are 1 cm long and open into 4 valves to release the seeds.

Distribution and habitat

The species only occurs in the

granite Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...

peaks, outcrops and drainage lines of the

Porongurup Range Porongurup National Park is a national park in the Great Southern region of Western Australia. It covers , and is southeast of Perth and north of Albany. The park contains the Porongurup Range, which is the relic core of an ancient mount ...

, in the

Jarrah Forest Jarrah forest is tall open forest in which the dominant overstory tree is ''Eucalyptus marginata'' (jarrah). The ecosystem occurs only in the Southwest Botanical Province of Western Australia. It is most common in the biogeographic region named in ...

IBRA The Interim Biogeographic Regionalisation for Australia (IBRA) is a biogeographic regionalisation of Australia developed by the Australian government's Department of Sustainability, Environment, Water, Population, and Communities. It was devel ...

bioregion of

Southwest Australia Southwest Australia is a biogeographic region in Western Australia. It includes the Mediterranean-climate area of southwestern Australia, which is home to a diverse and distinctive flora and fauna. The region is also known as the Southwest Aus ...

, mainly above an altitude of 400 m. There the plants occupy moist, shady positions in rock crevices and beneath overhangs. The soils are shallow sandy

loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–sil ...

s, containing accumulated organic material, that have water percolating through them in winter.

Conservation

The species has a restricted area of occurrence and limited population size, and is listed as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

under Australia's EPBC Act. The main threats include habitat degradation by

invasive weeds An invasive species otherwise known as an alien is an introduced species, introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, i ...

and grazing by

herbivore A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

s such as

rabbit Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit speci ...

s and

western grey kangaroo The western grey kangaroo (''Macropus fuliginosus''), also referred to as a western grey giant kangaroo, black-faced kangaroo, mallee kangaroo, sooty kangaroo and (when referring to the Kangaroo Island subspecies) Kangaroo Island grey kangaroo, is ...

s. Another potential threat is hybridisation with the closely related '' Ornduffia marchantii'', which has a similarly restricted range, though mostly at lower elevations, within the Porongurups.

References

calthifolia Asterales of Australia Eudicots of Western Australia Taxa named by Ferdinand von Mueller Plants described in 1868 {{Australia-asterid-stub