| Trithuria occidentalis | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Order: | Nymphaeales |
| Family: | Hydatellaceae |
| Genus: | Trithuria |
| Species: | T. occidentalis |
| Binomial name | |
| Trithuria occidentalis | |
 | |
| Trithuria occidentalis is endemic to Western Australia [2] | |
| Synonyms [2] | |
| |
Trithuria occidentalis is a species of plant in the family Hydatellaceae endemic to Western Australia. [2]
It is an annual, [3] [1] 2-3 cm tall, aquatic herb with 2-3 cm long, and 1 mm wide, red, linear leaves. [4] The midveins of the leaves are prominent. [3]
It is a dioecious species with unisexual reproductive units. It exhibits sexual dimorphism in respect to the number of bracts present in the reproductive units ("flowers"). [5] The male reproductive units consist of 3 mm long, erect stalks with 2 lanceolate, 7-8 mm long bracts, as well as 8-10 stamens. The stamens consist of linear, 3 mm long, faintly yellow anthers, and 1 cm long filaments. [3] The female plants produce smaller reproductive units [4] with 8–9(–12) [5] 1.5-2.2mm long bracts enclosing 8-10 carpels. [4] The dehiscent fruit [5] bears seeds, which are sculptured. [4] [5]
It is endemic to Western Australia, [2] where it is restricted to a small area north-east from Perth. [5]
Trithuria occidentalis Benth. was first described by George Bentham in 1878. Later synonyms include Juncella occidentalis (Benth.) Hieron. and Hydatella dioica D.A.Cooke. [2] The type specimen was collected by James Drummond [5] [4] [6] in Swan River, Western Australia. [5] It is placed in Trithuria sect. Trithuria. [7] [8] The description of Hydatella dioica D.A.Cooke was based on a male individual of Trithuria occidentalis Benth. [5] [9]
It is a threatened species. [12] Under the Western Australian Wildlife Conservation Act of 1950, it is declared as Rare Flora. According to the IUCN criteria, it is classified as Critically Endangered (CR). [4] It is classified as endangered both under the Environment Protection and Biodiversity Conservation Act 1999 and the Biodiversity Conservation Act 2016. [13] [1] In 1982, about 1000 plants were recorded. By 2007, the number of recorded individuals had dropped below 200 plants. [4]
It occurs in seasonal swamps, [3] and shallow, winter-wet claypans. [4]
Hydatellaceae are a family of small, aquatic flowering plants. The family consists of tiny, relatively simple plants occurring in Australasia and India. It was formerly considered to be related to the grasses and sedges, but has been reassigned to the order Nymphaeales as a result of DNA and morphological analyses showing that it represents one of the earliest groups to split off in flowering-plant phylogeny, rather than having a close relationship to monocots, which it bears a superficial resemblance to due to convergent evolution. The family includes only the genus Trithuria, which has at least 13 species, although species diversity in the family has probably been substantially underestimated.
Centrolepis is a genus of small herbaceous plants in the family Restionaceae known as thorn grass scales, with about 25 species native to Australia, New Zealand, New Guinea, and south-east Asia as far north as Hainan Dao. APG III system classifies this genus in the Centrolepidaceae family.
Podolepis is a genus of flowering plants in the tribe Gnaphalieae within the family Asteraceae. It is endemic to Australia and can be found in every state.
Trithuria is a genus of small ephemeral aquatic herb that represent the only members of the family Hydatellaceae found in India, Australia, and New Zealand. All 13 described species of Trithuria are found in Australia, with the exception of T. inconspicua and T. konkanensis, from New Zealand and India respectively. Until DNA sequence data and a reinterpretation of morphology proved otherwise, these plants were believed to be monocots related to the grasses (Poaceae). They are unique in being the only plants besides two members of Triuridaceae in which the stamens are centred and surrounded by the pistils; in Hydatellaceae the resulting 'flowers' may instead represent condensed inflorescences or non-flowers.
The Drummond Nature Reserve is an A class nature reserve 10 kilometres west of Bolgart, Western Australia. Named after the botanist James Drummond, the reserve has 439 species of vascular plants within its boundaries, including two rare and seven priority species.
Trithuria inconspicua is a small aquatic herb of the family Hydatellaceae that is only found in New Zealand.
Lomandra effusa is a perennial, dioecious, rhizomatous herb native to Australia. It is a perennial tussock with bluish green, large, arching leaves which are distinctive by the two toothed leaf tip. It has white, cream or pink fragrant flowers during the months of June to October.
Terry Desmond Macfarlane is a botanist and taxonomist, who has worked in both Australia and Peru. A senior research scientist at the Western Australian Herbarium, Macfarlane is associate editor of its journal Nuytsia and currently collaborates with researchers across Australia and in Canada, Germany, New Zealand, Russia, Spain and United Kingdom. He was also involved in the development of FloraBase, the Western Australian flora database.
Trithuria austinensis is a species of aquatic plant in the family Hydatellaceae endemic to Western Australia.
Trithuria australis is a species of aquatic plant in the family Hydatellaceae endemic to Western Australia.
Trithuria bibracteata is a species of aquatic plant in the family Hydatellaceae endemic to Western Australia.
Trithuria cookeana is a species of aquatic plant in the family Hydatellaceae endemic to the Northern Territory, Australia.
Trithuria cowieana is a species of aquatic plant in the family Hydatellaceae endemic to the Northern Territory, Australia.
Trithuria filamentosa is a species of aquatic plant in the family Hydatellaceae endemic to Tasmania, Australia.
Trithuria fitzgeraldii is a species of aquatic plant in the family Hydatellaceae endemic to Western Australia.
Trithuria konkanensis is a species of aquatic plant in the family Hydatellaceae endemic to India.
Trithuria lanterna is a species of plant in the family Hydatellaceae endemic to Australia.
Trithuria polybracteata is a species of plant in the family Hydatellaceae endemic to Western Australia.
Trithuria submersa is a species of plant in the family Hydatellaceae endemic to the Australian states New South Wales, South Australia, Tasmania, Victoria, and Western Australia.
Trithuria inconspicua subsp. brevistyla is a subspecies of Trithuria inconspicua in the family Hydatellaceae endemic to the South Island of New Zealand.
