Swainsona unifoliolata is a species of flowering plant in the family Fabaceae and is endemic to Central Australia. It is an erect or ascending perennial plant, usually with one leaflet and racemes of about 4 to 15 purple flowers.
Swainsona unifoliolata is an erect or ascending perennial herb up to high with leaves long with a single leaflet, or occasionally 3 leaflets, the leaflets egg-shaped, mostly long and wide. There is a stipule long at the base of the petiole. The flowers are arranged in racemes with 4 to 15 flowers on a peduncle wide, each flower long on a hairy pedicel usually long. The sepals are joined at the base, forming a tube long, the sepal lobes about the same length the tube. The petals are purple, the standard petal long and wide, the wings long, and the keel about long and deep. The fruit is narrowly elliptic and often curved, long and wide, with the remains of the curved or coiled style about long.[1] Flowering occurs from April to October.[2]
Swainsona unifoliolata was first formally described in 1874 by Ferdinand von Mueller in his Fragmenta Phytographiae Australiae.[3] [4] The specific epithet (unifoliolata) means "having one leaflet".[5]
This species of pea grows on gypsum or limestone on salt flats and the edges of salt lakes in the Avon Wheatbelt, Central Ranges, Gibson Desert, Great Sandy Desert, Great Victoria Desert, Little Sandy Desert, Murchison, Pilbara and Tanami bioregions of inland Western Australia, South Australia, and Finke, Great Sandy Desert, MacDonnell Ranges, Simpson Strzelecki Dunefields and Tanami bioregions of southern Northern Territory.