Micromyrtus grandis

Micromyrtus grandis, commonly known as Severn River heath-myrtle, is a species of flowering plant in the myrtle family. It is an upright, monoecious shrub with egg-shaped, oval or elliptic leaves arranged in opposite pairs and white to cream-coloured flowers arranged singly in leaf axils.

Description
Micromyrtus grandis grows as a monoecious shrub with an erect habit, usually reaching 1–4 m tall. The orange bark is stringy and shed in ribbons, which frequently curl. The leaves are 0.5–4.1 mm long by 0.6–1.4 mm wide. When held up to the light, their oil dots can be clearly seen in the leaf blade. The flowers are arranged singly in leaf axils on a peduncle 0.3–1.6 mm long, with 2 bracteoles 0.7–0.9 mm long at the base. The 5 petal-like sepals are 0.1–1.3 mm wide and the 5 petals white to cream-coloured, 0.5–1.2 mm long. There are 5 stamens, the filaments 0.1–0.3 mm long and the style is 0.1–0.5 mm long. Flowering occurs from July to September and the fruit is a brown nut 0.9–1.6 mm long.

Taxonomy and naming
John T. Hunter described Micromyrtus grandis in 1996, after coming across a colony of Micromyrtus on a porphyritic ridge that did not correspond to any known species. The description was first published in the journal Telopea from specimens collected in the Severn River Nature Reserve in northern New South Wales. Hunter gave it the species name grandis as it was the largest known species in the genus.

Distribution and habitat
Micromyrtus grandis is found along one long ridge at an altitude of 600 to 750 m in the Severn River Nature Reserve and adjoining private farmland. It grows in exposed locations in heath and open woodland, associated with such species as narrow-leaved ironbark (Eucalyptus crebra), stringybark she-oak (Allocasuarina inophloia), Acacia pubifolia, Johnson's grasstree (Xanthorrhoea johnsonii), and heath species Leptospermum novae-angliae, Micromyrtus sessilis and Leucopogon neoanglicus.

Conservation status
Severn River heath-myrtle is listed as "endangered" under the Australian Government Environment Protection and Biodiversity Conservation Act 1999 and the New South Wales Government Biodiversity Conservation Act 2016.

Cultivation
Micromyrtus grandis has been cultivated at the Australian National Botanic Gardens in Canberra since 1998, proving hardy and easy to grow, and can be propagated by seed or cutting.