Swainsona tanamiensis is a species of flowering plant in the family Fabaceae and is endemic to north-western Australia. It is a prostrate or erect perennial plant with imparipinnate leaves with 5 to 13 broadly egg-shaped to elliptic, or almost round leaflets, and racemes of up to 8 purple flowers.

Swainsona tanamiensis
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Genus: Swainsona
Species:
S. tanamiensis
Binomial name
Swainsona tanamiensis

Description

edit

Swainsona tanamiensis is a prostrate or erect perennial plant that typically grows to a height of up to about 25 cm (9.8 in), and has many hairy stems. Its leaves are imparipinnate, about 30–80 mm (1.2–3.1 in) long with 5 to 13 broadly egg-shaped to elliptic or almost round leaflets, the side leaflets mostly 1–15 mm (0.039–0.591 in) long and 3–8 mm (0.12–0.31 in) wide. There is a stipule mostly about 8 mm (0.31 in) long at the base of the petiole. The flowers are arranged in racemes 20–120 mm (0.79–4.72 in) long with up to 8 flowers on a peduncle 0.5–1.0 mm (0.020–0.039 in) wide, each flower about 15 mm (0.59 in) long on a pedicel about 2–3 mm (0.079–0.118 in) long. The sepals are joined at the base, forming a tube 2.0–2.5 mm (0.079–0.098 in) long, the sepal lobes about as long or somewhat shorter than the tube. The petals are purple, the standard petal 10–15 mm (0.39–0.59 in) long and 8–10 mm (0.31–0.39 in) wide, the wings 8–14 mm (0.31–0.55 in) long, and the keel about 10–15 mm (0.39–0.59 in) long and 3–6 mm (0.12–0.24 in) deep. Flowering occurs from April to July, and the fruit is mostly 15–30 mm (0.59–1.18 in) long and 3–4 mm (0.12–0.16 in) wide.[2][3]

Taxonomy and naming

edit

Swainsona tanamiensis was first formally described in 1993 by Joy Thompson in the journal Telopea from specimens collected by William Robert Barker near Lake Ruth in the Tanami Desert in 1975.[2][4] The specific epithet (tanamiensis) refers the Tanami Desert.[2]

Distribution and habitat

edit

This species of pea grows in clay or sandy soil on floodplains, and the edges of salt lakes in the Dampierland, Gascoyne, Great Sandy Desert, Pilbara and Tanami bioregions of Western Australia and the Northern Territory.[2][3][5]

References

edit
  1. ^ "Swainsona tanamiensis". Australian Plant Census. Retrieved 14 June 2024.
  2. ^ a b c d Thompson, Joy (1993). "A revision of the genus Swainsona (Fabaceae)". Telopea. 4 (1): 496–497. Retrieved 14 June 2024.
  3. ^ a b "Swainsona tanamiensis". FloraBase. Western Australian Government Department of Biodiversity, Conservation and Attractions. Retrieved 9 September 2022.
  4. ^ "Swainsona tanamiensis". Australian Plant Name Index. Retrieved 14 June 2024.
  5. ^ "Swainsona tanamiensis". Northern Territory Government. Retrieved 15 June 2024.