Swainsona katjarra

Swainsona katjarra
Conservation status
Declared rare  (DEC)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
Genus:	Swainsona
Species:	S. katjarra
Binomial name
Swainsona katjarra R.W.Davis & T.Hammer

Swainsona katjarra, commonly known as Birriliburu swainsona, ^[1] is a species of flowering plant in the family Fabaceae and is endemic to inland Western Australia. It is an erect annual herb with imparipinnate leaves with 4 to 6 lance-shaped to egg-shaped to elliptical leaflets, and racemes of 15 to 25 magenta flowers.

Description

Swainsona katjarra is an erect annual herb, that typically grows to a height of about 50 cm (20 in)and has several stems 2.5–5 mm (0.098–0.197 in) wide. Its leaves are imparipinnate, 60–90 mm (2.4–3.5 in) long on an elongated petiole with 4 to 6 egg-shaped to elliptical leaflets with the narrower end towards the base, 10–20 mm (0.39–0.79 in) long and 4–8 mm (0.16–0.31 in) wide. There are triangular stipules 8–10 mm (0.31–0.39 in) long at the base of the petiole. The flowers are arranged in racemes 100–200 mm (3.9–7.9 in) long with 15 to 25 flowers on a peduncle 50–70 mm (2.0–2.8 in) wide, each flower 8–11 mm (0.31–0.43 in) long on a pedicel 2.0–2.5 mm (0.079–0.098 in) long. The sepals are joined at the base, forming a tube 2–3 mm (0.079–0.118 in) long, the sepal lobes 3.5–4.5 mm (0.14–0.18 in) long. The petals are magenta, the standard petal 12–12.5 mm (0.47–0.49 in) long and 11–12 mm (0.43–0.47 in) wide, the wings purple and 9.5–11 mm (0.37–0.43 in) long, and the keel purple and 11–12 mm (0.43–0.47 in) long and 5.5–5.8 mm (0.22–0.23 in) deep. Flowering occurs has been observed in August, and the fruit is an elliptical pod 8–10 mm (0.31–0.39 in) long and hairy. ^{[2] [1]}

Taxonomy

Swainsona katjarra was first formally described in 2020 by Robert Davis and Timothy Hammer in the journal Swainsona from specimens collected on the south side of the Carnarvon Range. ^{[2] [3]} The specific epithet (katjarra) is the indigenous name for the Carnarvon Range. ^[2]

Distribution and habitat

This species of Swainsona is only known from the Carnarvon Range in the Gascoyne, Little Sandy Desert and Murchison bioregions of inland Western Australia. ^{[2] [1]}

Conservation status

Swainsona katjarra is listed as "Threatened Flora (Declared Rare Flora — Extant)" by the Western Australian Government Department of Biodiversity, Conservation and Attractions. ^[1]

References

1. "Swainsona katjarra". FloraBase . Western Australian Government Department of Biodiversity, Conservation and Attractions.
2. Davis, Robert W.; Hammer, Timothy A. (2020). "A key to the species of Swainsona (Fabaceae) in Western Australia and description of S. katjarra from the Little Sandy Desert region, Western Australia". Swainsona. 33: 144–146. Retrieved 22 February 2024.
3. "Swainsona katjarra". Australian Plant Name Index. Retrieved 22 February 2024.