| Trithuria bibracteata | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Order: | Nymphaeales |
| Family: | Hydatellaceae |
| Genus: | Trithuria |
| Species: | T. bibracteata |
| Binomial name | |
| Trithuria bibracteata | |
 | |
| Trithuria bibracteata is endemic to Western Australia [1] | |
Trithuria bibracteata is a species of aquatic plant in the family Hydatellaceae endemic to Western Australia. [1]
Trithuria bibracteata is a small, annual, aquatic herb [2] with simple, linear, 5-20 mm long, and 0.4 mm wide leaves. [3] The red plants are 1 cm wide, [4] and max. 2 cm high. [3] The short stem bears max. 2 mm long hairs. [4]
It is monoecious, [3] and the reproductive units ("flowers") are bisexual. [5] The reproductive units are sessile, [4] or pedunculate. [6] The reproductive unit consists of two lanceolate, 2-3 mm long, and 1.2 mm wide involucral bracts, 1-2 stamens, and 6-10 carpels. [4] The dehiscent fruit [3] bears 0.4-0.6 mm long, [4] desiccation-tolerant, [7] black to brown, [8] ellipsoid to ovoid seeds, [3] which require light to germinate. [9] [10] Flowering occurs from September to November. [2] [3]
It occurs in the Southwest region of the state Western Australia. [2] [3]
It was described in 1983 as Trithuria bibracteata Stapf ex D.A.Cooke by David Alan Cooke based on previous work by Otto Stapf. [1] [4] The type specimen was collected by R. D. Royce in Boyanup, Western Australia in l947. [4] It is placed in Trithuria sect. Trithuria. [11]
The specific epithet bibracteata is derived from the prefix bi- meaning two, [12] [13] and -bracteata meaning "with bracts". [14] [15] The reproductive units have two bracts. [4]
It is not threatened. [2]
It occurs in clay and mud along stream edges, [2] ephemeral pools, [16] and swamps. [8] [9] It inhabits winter-wet habitats, [2] [9] which dry in the Australian summer from December to February. [9] It can occur sympatrically with Trithuria occidentalis . [17]
The desiccation-tolerant seeds [7] may be dispersed by water birds. [10]
The Nymphaeales are an order of flowering plants, consisting of three families of aquatic plants, the Hydatellaceae, the Cabombaceae, and the Nymphaeaceae. It is one of the three orders of basal angiosperms, an early-diverging grade of flowering plants. At least 10 morphological characters unite the Nymphaeales. One of the traits is the absence of a vascular cambium, which is required to produce both xylem (wood) and phloem, which therefore are missing. Molecular synapomorphies are also known.
Hydrocharitaceae is a flowering plant family including 16 known genera with a total of ca 135 known species, that including a number of species of aquatic plant, for instance the tape-grasses, the well known Canadian waterweed, and frogbit.
The Cabombaceae are a family of aquatic, herbaceous flowering plants. A common name for its species is water shield. The family is recognised as distinct in the Angiosperm Phylogeny Group IV system (2016). The family consists of two genera of aquatic plants, Brasenia and Cabomba, totalling six species.
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.
A pseudanthium is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers, or capitula, which are special types of inflorescences in which anything from a small cluster to hundreds or sometimes thousands of flowers are grouped together to form a single flower-like structure. Pseudanthia take various forms. The real flowers are generally small and often greatly reduced, but the pseudanthium itself can sometimes be quite large.
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.
Trithuria inconspicua is a small aquatic herb of the family Hydatellaceae that is only found in New Zealand.
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 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 occidentalis is a species of plant in the family Hydatellaceae endemic to Western 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.