Pimelea microcephala, commonly known as mallee rice-flower or shrubby rice-flower is a species of flowering plant in the family Thymelaeaceae and is endemic to mainland Australia. It is an erect shrub with compact heads of male or female, white to yellow or greenish flowers on separate plants, the heads surrounded by 2 or 4 leaf-like involucral bracts.
Description
Pimelea microcephala is an erect, dioecious shrub that typically grows to a height of 0.7–4m (2ft 4in– 13ft 1in) and has glabrous stems. Its leaves are arranged in opposite pairs, linear to more or less narrowly elliptic, mostly 7–40mm (0.28–1.57in) long and 1–4mm (0.039–0.157in) wide on a short petiole. The flowers are white to yellow or greenish and arranged on the ends of branches in compact heads on a peduncle2–13mm (0.079–0.512in) long. The flowers are glabrous inside and usually densely curly-hairy on the outside, on a hairy pedicel. Male flowers are in heads of 8 to 100 flowers, the floral tube3–7mm (0.12–0.28in) long. Female flowers are in heads of 7 to 12, each 2–4mm (0.079–0.157in) long. The sepals are 0.2–2mm (0.0079–0.0787in) long and the stamens of male flowers are shorter than the sepals. Flowering mainly occurs from April to September and the fruit is a succulent, red nut.
Pimelea microcephala subsp. glabra (F.Muell. & Tate ex J.M.Black) Threlfall (previously known as Pimelea microcephala var. glabra F.Muell. & Tate ex J.M.Black) has 8 to 64 male flowers, the floral tube 4–5mm (0.16–0.20in) long and the flowers sparsely hairy on the outside and often becoming glabrous.
Pimelea microcephala R.Br. subsp. microcephala has 13 to 100 male flowers, the floral tube 3–8mm (0.12–0.31in) long and the flowers are covered with short, fine, curly hairs on the outside.
12Rye, Barbara L. "Pimelea microcephala". Flora of Australia. Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 5 February 2023.
↑Rye, Barbara L. "Pimelea microcephala subsp. glabra". Flora of Australia. Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 6 February 2023.
↑Rye, Barbara L. "Pimelea microcephala subsp. microcephala". Flora of Australia. Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 6 February 2023.