Swainsona lessertiifolia

Swainsona lessertiifolia
At Cape Schanck
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
Genus:	Swainsona
Species:	S. lessertiifolia
Binomial name
Swainsona lessertiifolia DC.[1]
Synonyms[1]
Swainsona astragalifolia Sweet nom. inval., nom. nud. Swainsona froebelii Regel Swainsona lessertiaefolia DC. orth. var. Swainsona lessertiifolia DC. var. lessertiifolia Swainsonia lessertiifolia F.Muell. orth. var.

Swainsona lessertiifolia, commonly known as coast swainson-pea, bog pea, Darling pea poison pea or poison vetch[2] is an erect or ascending perennial herb in the pea family and is endemic to south-eastern Australia. It has 13 to 21 narrowly elliptic to elliptic leaflets, and racemes of mostly 12 to 25 usually purplish, rarely white flowers.

Description

Swainsona lessertiifolia is an erect or ascending perennial herb that typically grows up to 50 cm (20 in) tall. Its leaves are mostly 60–90 mm (2.4–3.5 in) long with 13 to 21 narrowly elliptic to elliptic leaflets 4–25 mm (0.16–0.98 in) long and 2–10 mm (0.079–0.394 in) wide with hairy stipules 2–7 mm (0.079–0.276 in) long at the base of the petioles. The flowers are arranged in racemes mostly 100–300 mm (3.9–11.8 in) long with 12 to 25 flowers on a peduncle 1–2 mm (0.039–0.079 in) wide, each flower 8–10 mm (0.31–0.39 in) long on a hairy pedicel about 2–4 mm (0.079–0.157 in) long. The sepals are joined at the base, forming a hairy black, bell-shaped tube 2.0–2.5 mm (0.079–0.098 in) long, the sepal lobes usually shorter than the tube. The petals are dark to pale purple, rarely white, the standard petal 10–11 mm (0.39–0.43 in) long and 8–16 mm (0.31–0.63 in) wide, the wings 7–8 mm (0.28–0.31 in) long, and the keel 8–10 mm (0.31–0.39 in) long and 4 mm (0.16 in) deep. Flowering mostly occurs from August to January and the fruit is elliptic, 10–30 mm (0.39–1.18 in) and 5–8 mm (0.20–0.31 in) wide.[2][3][4]

Taxonomy

Swainsona lessertiifolia was first formally described in 1825 by Augustin Pyramus de Candolle in Annales des Sciences Naturelles.[5][6]

Distribution and habitat

This species of swainsona occurs in South Australia, Victoria and Tasmania, often on sand hummocks in near-coastal areas. In South Australia it is found in the south-east of the state,[2] in Victoria it is abundant, mostly west of Wilsons Promontory[3][7] and in Tasmania grows at Woolnorth, St Marys and on Bass Strait Islands.[8]

References

1. "Swainsona lessertiifolia". Australian Plant Census. Retrieved 18 March 2024.
2. "Swainsona lessertiifolia". State Herbarium of South Australia. Retrieved 18 March 2024.
3. Jeanes, Jeff A.; Stajsic, Val. "Swainsona lessertiifolia". Royal Botanic Gardens Victoria. Retrieved 18 March 2024.
4. Thompson, Joy (1993). "A revision of the genus Swainsona (Fabaceae)". Telopea. 5 (3): 511–513. Retrieved 18 March 2024.
5. "Swainsona lessertiifolia". APNI. Retrieved 18 March 2024.
6. de Candolle, Augustin P. (1825). "Notice sur quelques genres et speces nouvelles de legumineuses, extraite de divers Memoires presentes a la Societe d'Histoire naturelle de Geneve, pendant le cours des annees 1823 et 1824". Annales des Sciences Naturelles. Série 1. 4: 99–100. Retrieved 18 March 2024.
7. Longmore, Sue; Smithyman, Steve & Crawley, Matt (2010). Coastal Plants of the Bellarine Peninsula. Bellarine Catchment Network.
8. Rodway, Leonard (1903). The Tasmanian Flora. Hobart: Tasmanian Government Printer. p. 38. Retrieved 18 March 2024.