Stylidium aquaticum is a dicotyledon

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...

). The specific epithet aquaticum refers to this species' typical habitat. 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 18 to 30 cm tall. Linear

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 20-100 per plant, are scattered along the elongate, glabrous stem. The leaves are generally 1.7–11 mm long and 0.1-0.3 mm wide. Petioles

Petiole (botany)

In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

 and 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 3–8 cm long. Flowers are pink or white. S. aquaticum is only known from its type location

Biological type

In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...

 in northwestern 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...

 of Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. Its habitat is recorded as being a 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....

swamp, growing in shallow water at a depth of around 7 cm. It flowers 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"...

 in May. S. aquaticum is most closely related to S. fissilobum

Stylidium fissilobum

Stylidium fissilobum is a dicotyledonous plant that belongs to the genus Stylidium . It is an annual plant that grows from 5 to 50 cm tall. Linear or deltate leaves, about 4-34 per plant, are scattered along the elongate, glabrous stem. The leaves are generally 1–6 mm long and...

but differs mostly in the leaf shape. 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...

.