Patersonia spirifolia, also known as the Spiral-leaved patersonia, is listed as Endangered under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and as Endangered under the Wildlife Conservation Act 1950.
The main threats to the Spiral-leaved patersonia are the its restricted extent of occurrence, highly fragmented distribution, low population size and continued declines in the number of mature individuals and the quality of habitat.
The Spiral-leaved patersonia is a perennial herb growing to 50 cm tall with a spreading woody rootstock producing a tussock up to 40 cm wide. The leaves are linear, spirally twisted, up to 20 cm long and 5 mm wide.
The brown leaf margins have fringes of soft hairs that point towards the centre of the leaf. The scape (leafless flowering stem) is up to 25 cm long, 1-2 mm wide and reddish-green. The spathe (a leaf-like structure enveloping the flower cluster) is brown in colour, lance-shaped and up to 26 mm long with thin, almost transparent margins.
The flowers have three broad, mauve to blue-violet coloured sepals (petal-like structures) up to 19 mm long and 14 mm wide, and three very small, upright, blue-violet coloured petals about 1 mm long. The seed capsule is roughly egg-shaped and up to 3 cm long.
Six populations of the spiral-leaved patersonia have been recorded in the region up to 10 km south-west of Badgingarra, Western Australia, since the species was identified in 1988. One population is located in Badgingarra National Park and the remainder occur in road reserves outside the national park.
The Spiral-leaved patersonia is found on lateritic ridges and slopes, or sand over laterite in low species-rich heath.
Associated species include Allocasuarina humilis, Daviesia chapmanii, D. epiphyllum, Gastrolobium spinosum, Mesomelaena stygia, M. tetragona, Patersonia occidentalis and Xanthorrhoea preissii
Information Source: Government of Australia, Department of Environment and Department of Parks and Wildlife Western Australia