Pimelea, commonly known as rice flowers, is a genus of plants belonging to the family Thymelaeaceae. There are about 150 species, including 110 in Australia and 36 in New Zealand. Description Plants in the genus Pimelea are herbs or small shrubs, usually with leaves arranged in opposite pairs. The leaves are usually paler on the lower surface and the petiole is usually very short. The flowers are usually arranged in groups on the ends of the branches and have no petals, but four petal-like sepals and two stamens. The ovary has a single ovule and the fruit is usually a nut containing a single seed. Taxonomy and naming The genus Pimelea was first formally described in 1788 by Joseph Gaertner from unpublished descriptions by Joseph Banks and Daniel Solander. The first species Gaertner described was Pimelea laevigata, now known as Pimelea prostrata. The name Pimelea is from the Ancient Greek word pimele, meaning "fat or "lard", possibly referring to the oily seeds or fleshy cotyledons of riceflowers. Ecology Some species, including P. curviflora, P. flava, P. glauca, P. linifolia, P. microcephala, P. neo-anglica, P. pauciflora, P. simplex and P. trichostachya, are toxic to stock; there is no known cure. Species About 150 species of Pimelea have been formally described, including about 110 in Australia and 36 in New Zealand. The following is a combined list of names accepted by the Australian Plant Census or the New Zealand Plant Conservation Network as of December 2021. Pimelea acra C.J.Burrows & de Lange (N.Z.) Pimelea actea C.J.Burrows (N.Z.) Pimelea aeruginosa F.Muell. (W.A.) Pimelea alpina F.Muell. ex Meisn. – alpine riceflower (N.S.W., Vic.) Pimelea altior F.Muell. (Qld., N.S.W.) Pimelea amabilis (Domin) A.R.Bean (Qld.) Pimelea ammocharis F.Muell. (W.A.) Pimelea angustifolia R.Br. (W.A.) Pimelea approximans A.R.Bean (Qld.) Pimelea aquilonia Rye (Qld.) Pimelea argentea R.Br. – silvery leaved pimelea (W.A.) Pimelea aridula Cheeseman (N.Z.) Pimelea avonensis Rye (W.A.) Pimelea axiflora F.Muell. ex Meisn. – bootlace bush (N.S.W., Vic., Tas.) Pimelea axiflora subsp. alpina Pimelea axiflora subsp. axiflora Pimelea axiflora subsp. pubescens Pimelea barbata C.J.Burrows (N.Z.) Pimelea biflora N.A.Wakef. – matted rice flower (N.S.W.,Vic.) Pimelea brachyphylla Benth. (W.A.) Pimelea bracteata Threlfall (N.S.W.) Pimelea brevifolia R.Br. (W.A.) Pimelea brevifolia subsp. brevifolia Pimelea brevifolia subsp. modesta Pimelea brevistyla Rye (W.A.) Pimelea brevistyla subsp. brevistyla Pimelea brevistyla subsp. minor Pimelea buxifolia Hook.f. (N.Z.) Pimelea calcicola Rye (W.A.) Pimelea carnosa C.J.Burrows (N.Z.) Pimelea chlorina A.R.Bean (Qld.) Pimelea ciliata Rye (W.A.) Pimelea ciliata