Stylidium nominatum
Encyclopedia
Stylidium nominatum is a dicotyledon
ous plant
that belongs to the genus
Stylidium (family Stylidiaceae
). It is an annual plant
that grows from 4 to 15 cm tall. The oblanceolate
leaves, about 5-15 per plant, form basal rosettes
around the stem and are 2.5-9 mm long, 0.5-1.5 mm wide. About 4-11 leaves per plant are also scattered along the stem and are generally 2.3-4.7 mm long and 0.3-0.5 mm wide. Scapes
are absent. Inflorescence
s are 2-6 cm long and produce white flowers that bloom from April to June in the southern hemisphere
. S. nominatum is endemic to the northern area of Kakadu National Park
and Melville Island
in the Northern Territory
. Its habitat is recorded as being sandy soils in Melaleuca viridiflora
woodlands, bases of sandstone escarpments, and gravelly yellow soil in flat, treeless areas. S. nominatum is most closely related to S. capillare
. In his recent revision of the subgenus Andersonia, A. R. Bean noted that there is a large variation recorded in the specimens of this species and more work would need to be done to determine if there's more than one taxon involved with this species. Further evaluation may reveal additional species.
S. mitrasacmoides
is an illegitimate name applied to this species that had been described by Sherwin Carlquist
as a new species in 1979. Ferdinand von Mueller
had described a species under this name in 1859 and it is now applied as a synonym for S. tenerrimum
, though A. R. Bean noted that this application is uncertain because the type specimen
was unable to be located. Its conservation status
has been assessed as data deficient
.
Dicotyledon
The dicotyledons, also known as dicots, are a group of flowering plants whose seed typically has two embryonic leaves or cotyledons. There are around 199,350 species within this group...
ous plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
that belongs to the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Stylidium (family Stylidiaceae
Stylidiaceae
The family Stylidiaceae is a taxon of dicotyledonous flowering plants. It consists of five genera with over 240 species, most of which are endemic to Australia and New Zealand. Members of Stylidiaceae are typically grass-like herbs or small shrubs and can be perennials or annuals...
). It is an annual plant
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...
that grows from 4 to 15 cm tall. The oblanceolate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
leaves, about 5-15 per plant, form basal rosettes
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
around the stem and are 2.5-9 mm long, 0.5-1.5 mm wide. About 4-11 leaves per plant are also scattered along the stem and are generally 2.3-4.7 mm long and 0.3-0.5 mm wide. Scapes
Scape (botany)
In botany, scapes are leafless flowering stems that rise from the ground. Scapes can have a single flower or many flowers, depending on the species....
are absent. Inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
s are 2-6 cm long and produce white flowers that bloom from April to June in the southern hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
. S. nominatum is endemic to the northern area of Kakadu National Park
Kakadu National Park
Kakadu National Park is in the Northern Territory of Australia, 171 km southeast of Darwin.Kakadu National Park is located within the Alligator Rivers Region of the Northern Territory of Australia. It covers an area of , extending nearly 200 kilometres from north to south and over 100 kilometres...
and Melville Island
Melville Island, Northern Territory
Melville Island or Yermalner Island lies in the eastern Timor Sea, off the coast of the Northern Territory of Australia. It is west of the Cobourg Peninsula in Arnhem Land and north of Darwin....
in the Northern Territory
Northern Territory
The Northern Territory is a federal territory of Australia, occupying much of the centre of the mainland continent, as well as the central northern regions...
. Its habitat is recorded as being sandy soils in Melaleuca viridiflora
Melaleuca viridiflora
Melaleuca viridiflora, known as broad-leaved paperbark, is a small tree native to woodlands, swamps and streams of monsoonal northern Australia and Papua New Guinea....
woodlands, bases of sandstone escarpments, and gravelly yellow soil in flat, treeless areas. S. nominatum is most closely related to S. capillare
Stylidium capillare
Stylidium capillare is a dicotyledonous plant that belongs to the genus Stylidium . It is an annual plant that grows from 6 to 13 cm tall. Obovate or orbicular leaves, about 4-7 per plant, form basal rosettes around the compressed stems. The leaves are generally 1.5–5 mm long and...
. In his recent revision of the subgenus Andersonia, A. R. Bean noted that there is a large variation recorded in the specimens of this species and more work would need to be done to determine if there's more than one taxon involved with this species. Further evaluation may reveal additional species.
S. mitrasacmoides
Stylidium mitrasacmoides
Stylidium mitrasacmoides is a taxonomic synonym that has been applied to the following species:* Stylidium nominatum - Stylidium mitrasacmoides is an illegitimate name applied to this species and was described in 1979, later being renamed to avoid the earlier usage.* Stylidium tenerrimum -...
is an illegitimate name applied to this species that had been described by Sherwin Carlquist
Sherwin Carlquist
Sherwin Carlquist is an American botanist and photographer. He received his undergraduate degree from the University of California, Berkeley in 1952 and a Ph.D. in botany in 1956, also at Berkeley. Carlquist did a postdoctoral study at Harvard University from 1955 to 1956. After his postdoctoral...
as a new species in 1979. Ferdinand von Mueller
Ferdinand von Mueller
Baron Sir Ferdinand Jacob Heinrich von Mueller, KCMG was a German-Australian physician, geographer, and most notably, a botanist.-Early life:...
had described a species under this name in 1859 and it is now applied as a synonym for S. tenerrimum
Stylidium tenerrimum
Stylidium tenerrimum is a dicotyledonous plant that belongs to the genus Stylidium . It is an erect annual plant that grows from 4 to 30 cm tall. Linear, oblanceolate, or deltate leaves, about 5-24 per plant, are scattered along the stems. The leaves are generally 1.2-4.8 mm long and...
, though A. R. Bean noted that this application is uncertain because the type specimen
Biological type
In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...
was unable to be located. Its conservation status
Conservation status
The conservation status of a group of organisms indicates whether the group is still extant and how likely the group is to become extinct in the near future...
has been assessed as data deficient
Data Deficient
Data Deficient is a category applied by the IUCN, other agencies, and individuals to a species when the available information is not sufficient for a proper assessment of conservation status to be made...
.