Swainsona oliveri is a species of flowering plant in the family Fabaceae and is endemic to south-western Australia. It is a slender, prostrate to ascending annual or perennial herb with imparipinnate leaves with 9 to 13 narrowly egg-shaped leaflets, the narrower end towards the base, and racemes of up to 4 cream-coloured to yellow flowers, sometimes with a pink tinge.
Swainsona oliveri is a slender prostrate to ascending annual or perennial herb, that typically grows to a height of about and has radiating stems. The leaves are imparipinnate, mostly long with 9 to 13 egg-shaped leaflets with the narrower end towards the base, the side leaflets long and wide with stipules long at the base of the petioles. The flowers are cream-coloured to yellow, sometimes tinged with pink, arranged in racemes of up to 4 on a peduncle up to long. The sepals are joined at the base to form a tube about long, with lobes shorter than the tube. The standard petal is long and wide, the wings long and the keel about long and deep.[1] Flowering occurs from August to September, and the fruit is a narrowly elliptical pod long and wide with the remains of the style long.
Swainsona oliveri was first formally described in 1882 by Ferdinand von Mueller in Southern Science Record from a specimens collected near Port Eucla by John Oliver.[2] [3] The specific epithet (oliveri) honours the collector of the type specimens.[4]
This species of swainsona grows on sandy plains and is widespread in South Australia[5] and in the Avon Wheatbelt, Coolgardie, Great Victoria Desert, Hampton, Murchison and Nullarbor bioregions of Western Australia. It also occurs in the far western plains of New South Wales[6] and the south of the Northern Territory.[7]