Swainsona extrajacens is a species of flowering plant in the family Fabaceae and is endemic to central Australia. It is an erect, annual plant with imparipinnate leaves with 9 to 21 linear, egg-shaped leaflets, and racemes of purple flowers in racemes of 5 to 10.
Swainsona extrajacens is an erect, apparently annual, with one to several stems mostly wide, that typically grows to high. The leaves are imparipinnate, long with 9 to 25 linear, egg-shaped leaflets mostly long and wide with narrowly lance-shaped stipules about long at the base of the petioles. The flowers are purple, arranged in racemes of 5 to about 10 on a peduncle wide with broadly lance-shaped bracts about long at the base. The sepals are joined at the base, forming a tube about long with lobes shorter than the tube. The standard petal is long and wide, the wings long and the keel long and about deep.[1] [2]
Swainsona extrajacens was first formally described in 1990 by Joy Thompson in the journal Telopea, from specimens collected on the far north-western plains of New South Wales in 1974.[3] [4] The specific epithet (extrajacens) means "remote from populated areas.
This species of pea grows in clay-loam floodplain in the north-western Corner of New South Wales and the north-eastern corner of South Australia.