Pimelea axiflora

Pimelea axiflora, commonly known as bootlace bush, is a small shrub in the family Thymelaeaceae and is endemic to Australia. It is a small shrub with whitish flowers on mostly smooth stems.

Description
Pimelea axiflora is a small dioecious shrub 0.2-3 m high with smooth stems or occasionally hairy. The leaves are arranged in opposite pairs are mostly linear or narrowly elliptic, upper surface mid-green, underside paler, 5-60 mm long, 2-10 mm wide on a petiole 3 mm long. The leaves are green, smooth and leaf margins mostly recurved. The inflorescence consists of a cluster of 2-10 white flowers in leaf axils with little or no stalk. The male flowers are larger, 5-9 mm long and female 3-6 mm long. The 2-4 flower bracts are usually oval shaped and 1.5-7 mm long and 1-2.5 mm wide. The green fruit are 3-4 mm long.

Taxonomy
Pimelea axiflora was first formally described in 1854 by Carl Meisner and the description was published in Linnaea: ein Journal für die Botanik in ihrem ganzen Umfange, oder Beiträge zur Pflanzenkunde.

There are currently three subspecies accepted by the Australian Plant Census:


 * P. axiflora subsp. F.Muell. ex Meisn. axiflora, it has soft leaves 10–75 mm long, flowers thickly covered with hairs on outside near petiole, bracts usually hairy on outside. Flowering occurs from June to December. In Tasmania it is restricted to King Island. In New South Wales it grows on the coast and ranges, south of the Budawang National Park to Braidwood. A single recording north of  Cooma and rare in the Snowy Mountains.  This subspecies grows in wetter locations as an understory shrub in eucalypt scrubland and near streams.


 * P. axiflora subsp. subsp. alpina (Benth.) Threlfall, commonly known as alpine bootlace bush, is a small shrub to 1 m high, sometimes semi-prostrate, smooth stems with leaf scars. The leaves are smooth, straight, leathery, 0.3–1.8 cm long, 1-8 mm wide and smooth bracts, 2-5 flowers in each cluster, moderate to infrequently hairy externally in montane locations. Male flowers are  4-6 mm long, female 3-6 mm long and the bracts are brown, smooth and usually 2-4 mm long. This species grows at higher altitudes in the Snowy Mountains in  open heath, rocky sites, woodland and herb and grass fields. Flowering occurs from November to March.


 * P. axiflora subsp. pubescens Rye, commonly known as Bungonia rice-flower, is a dioecious shrub to 3 m high, stems either smooth or hairy, new stem growth with hairs 1 mm long. The petiole 3 mm long, underside of leaves hairy, 0.5-6 cm long and 2-10 mm wide, linear to narrowly oval, margins curled under. The  upper leaf surface usually smooth and secondary veins on underside obvious. The  female flowers are 3-4 mm long, male 5-9 mm long, 2-10 white flowers in each cluster in leaf axils, 2-4 bracts 2-7 mm long and stalk more or less absent. Fruit are green and about 3-4 mm long. Flowering occurs in September. It is only found in the Bungonia National Park south east of Goulburn N.S.W where it grows on rocky, limestone outcrops and cliffs.

Distribution
Bootlace bush is found at higher altitudes on the Grampians extending to the east coast in Victoria, in south-eastern New South Wales and on King Island, Tasmania.

Conservation status

 * P. axiflora subsp. axiflora is listed as "endangered'' under the Threatened Species Protection Act 1995, Tasmania.


 * P. axiflora subsp. alpina is considered rare in Victoria.


 * P. axiflora subsp. pubescens is listed as "endangered" under the Environment Protection and Biodiversity Conservation Act due to be known from a single population containing a low number of mature plants.