Pimelea humilis

{{Taxobox | name = Pimelea humilis | image = Pimelea humilis flowers.jpg | image_caption = Flowers of Pimelea humilis | regnum = [[Plantae]] | divisio = [[Angiosperms]] | clades = [[Eudicots]] | ordo = [[Malvales]] | familia = [[Thymelaeaceae]] | genus = [[Pimelea]] | species = P. humilis | binomial = ''Pimelea humilis'' | binomial_authority = [[Robert Brown|R.Br.]] }}

Pimelea humilis, commonly known as Dwarf Rice-flower or Low Rice-flower, is a species of flowering plant in the family [[Thymelaeaceae]]. It is [[endemic]] to southeastern [[Australia]].

Description

Pimelea humilis is a small, [[prostrate]] to erect [[shrub]] typically growing to 5–30 cm (2–12 in) high and often spreading to 50 cm (20 in) or more in diameter. Its stems are often reddish and may be sparsely or densely hairy. The leaves are generally arranged in opposite pairs along the stems, though occasionally they can be sub-opposite or alternate. They are typically narrow-elliptic, linear-oblong, or obovate, 5–30 mm (0.2–1.2 in) long and 1–9 mm (0.04–0.35 in) wide. The leaves are smooth (glabrous) or have scattered hairs, and are usually pale green, sometimes tinged with red, especially in cooler conditions.

The flowers are cream, white, or pale yellow, often tinged with pink or red, and are borne in dense, terminal heads, usually with 5 to 20 individual flowers. These heads are typically surrounded by 4 to 6 (sometimes up to 10) leaf-like [[bract]]s, which are similar in size and shape to the leaves, though sometimes broader. Each flower is [[bisexual]] and lacks petals, instead having a tubular [[perianth]] that is 5–13 mm (0.2–0.5 in) long. The tube is often hairy on the outside and has four spreading lobes. There are two stamens, which are shorter than the perianth lobes. Flowering occurs mainly from late winter to early summer, typically between August and December, but can extend into autumn in some regions. The fruit is a small, dry nut enclosed within the persistent perianth tube.

Taxonomy and Naming

Pimelea humilis was first formally described by [[Robert Brown]] in 1810 in his work ''[[Prodromus Florae Novae Hollandiae et Insulae Van Diemen]]''. The [[specific epithet]] ''humilis'' is [[Latin]] for "low" or "humble," referring to the plant's typically low-growing habit.

Distribution and Habitat

The Dwarf Rice-flower is native to southeastern Australia, where it is found in [[New South Wales]], [[Victoria (Australia)|Victoria]], [[South Australia]], and [[Tasmania]]. It typically grows in a variety of habitats including [[eucalypt]] [[woodland]]s, open forests, [[heathland]]s, and [[grassland]]s. It prefers well-drained soils, often sandy or stony, and can be found in full sun to partial shade.

Conservation Status

Pimelea humilis is not currently listed as a threatened species at a national level in Australia. While some local populations may face pressures from habitat loss or degradation, it remains relatively widespread and common throughout its range.

Ecology

Like other Pimelea species, P. humilis flowers are a source of nectar for various native insects, including bees and butterflies, contributing to pollination. The plant's tough, fibrous stems and leaves are unpalatable to most grazing animals, and some Pimelea species contain compounds that can be toxic to livestock, though P. humilis is not widely known for this property.