Swainsona rostellata is a species of flowering plant in the family Fabaceae and is endemic to inland areas of Western Australia. It is a prostrate perennial herb with imparipinnate leaves with 7 to 13 wedge-shaped leaflets, and racemes of usually up to 3 purple flowers.
Swainsona rostellata is a prostrate, perennial herb that typically grows to a height of up to high and wide with sparsely hairy stems. Its leaves are imparipinnate, long on a sometimes very long petiole, with 7 to 13 wedge-shaped leaflets, the side leaflets long and wide. There is a variably shaped stipule long at the base of the petiole. The flowers are arranged in racemes long with up to 3 flowers on a peduncle about long, the flowers variable in size from long on a pedicel long. The sepals are joined at the base, forming a tube about long, the sepal lobes almost as long as the tube. The petals are purple, the standard petal long and wide, the wings long, and the keel about long and deep.[1] Flowering occurs from July to September and the fruit is about long and wide.
Swainsona rostellata was first formally described in 1948 by Alma Theodora Lee in Contributions from the New South Wales National Herbarium, from specimens collected by Charles Gardner on Mount Magnet in 1931.[2] The specific epithet (rostellata) means "possessing a small beak or snout", referring to the tip of the keel.[3]
This species of pea grows red soil or clay loam on the edges of salt lakes or near swamps, in the Coolgardie, Murchison and Yalgoo bioregions of inland Western Australia.