Bertya tasmanica

Bertya tasmanica
Subsp. vestita in the Little Desert National Park
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Malpighiales
Family:	Euphorbiaceae
Genus:	Bertya
Species:	B. tasmanica
Binomial name
Bertya tasmanica (Sond. & F.Muell.) Müll.Arg. [1]
Occurrence data from the Australasian Virtual Herbarium
Synonyms [1]
Ricinocarpos tasmanicusSond. & F.Muell. Ricinocarpus tasmanicusSond. & F.Muell. orth. var.

Subsp. tasmanica in the Tasmanian Bushland Garden

Bertya tasmanica is a species of flowering plant in the family Euphorbiaceae and is endemic to south-eastern Australia. It is a monoecious, or sometimes dioecious shrub with strap-like to linear leaves, and more or less sessile flowers borne singly in leaf axils, male flowers with 15 to 55 stamens and female flowers with hairy ovaries, the fruit a narrowly elliptic to narrowly oval capsule.

Description

Bertya tasmanica is a monoecious or sometimes dioecious shrub that typically grows to a height of up to 2.5 m (8 ft 2 in) with densely hairy branchlets at first, later glabrous. The leaves are strap-like to linear, 8–32 mm (0.31–1.26 in) long and 1.2–1.6 mm (0.047–0.063 in) wide on a petiole 1.0–3.1 mm (0.039–0.122 in) long. The upper surface of the leaves is green to greyish-green, and the lower surface white and densely covered with star-shaped hairs. ^{[2] [3] [4]}

The flowers are usually arranged singly, more or less sessile, the male flowers with five yellowish, egg-shaped, elliptic or oblong sepal lobes 2.4–5.1 mm (0.094–0.201 in) long and 2.0–3.2 mm (0.079–0.126 in) wide, and 15 to 55 stamens. Female flowers have five light green, narrowly egg-shaped to narrowly triangular, light green sepal lobes with a reddish tinge,1.8–4.3 mm (0.071–0.169 in) long, 0.7–1.9 mm (0.028–0.075 in) wide, and there are usually no petals. The ovary is elliptic, about 13–2.2 mm (0.512–0.087 in) long and 1.1–1.7 mm (0.043–0.067 in) wide and densely hairy, the style 0.1–0.6 mm (0.0039–0.0236 in) long usually with three spreading maroon or pale yellow limbs 1.6–2.9 mm (0.063–0.114 in) long, each with two to four lobes 1.0–2.3 mm (0.039–0.091 in) long. Flowering time depends on subspecies, and the seeds are light brown 3.9–5.2 mm (0.15–0.20 in) long and 1.8–3.1 mm (0.071–0.122 in) wide. ^{[2] [3] [4]}

Taxonomy

This species was first formally described in 1857 by Otto Wilhelm Sonder and Ferdinand von Mueller who gave it the name Ricinocarpos tasmanicus in the journal Linnaea . ^{[5] [6]} In 1865, Johannes Müller Argoviensis transferred the species to Bertya as B. tasmanica in a later edition of the same journal. ^{[7] [8]}

The names of two subspecies of B. tasmanica are accepted by the Australian Plant Census:

• Bertya tasmanica(Sond. & F.Muell.) Müll.Arg. subsp. tasmanica ^[9] has leaves 8–21 mm (0.31–0.83 in) long, peduncles 0.8–1.4 mm (0.031–0.055 in) long, fruit 5.6–6.5 mm (0.22–0.26 in) long and flowers from September to November. ^[10]
• Bertya tasmanica subsp. vestitaHalford & R.J.F.Hend. ^[11] has leaves 8–32 mm (0.31–1.26 in) long, peduncles 0.7–1.0 mm (0.028–0.039 in) long, fruit 6.4–8 mm (0.25–0.31 in) long and flowers mostly from September to December. ^[12]

Distribution and habitat

Bertya tasmanica subsp. vestita, is widespread from near Kimba in South Australia, ^{[2] [13]} eastwards to Swan Hill in Victoria ^[14] near Coonabarabran and the Southern Tablelands of New South Wales where it mainly grows on sandplains or sand dunes in heath, shrubland, woodland or heath. ^{[2] [4]}

Subspecies tasmanica grows near watercourses in heath or woodland between Bicheno and Cranbrook on the east coast of Tasmania. ^[2]

Conservation status

Bertya tasmanica subsp. tasmanica is listed as "endangered" under the Australian Government Environment Protection and Biodiversity Conservation Act 1999 ^[15] and the Tasmanian Government Threatened Species Protection Act 1995 . ^[16]

References

1. "Bertya tasmanica". Australian Plant Census. Retrieved 19 May 2025.
2. Halford, David A.; Henderson, Rodney John Francis (2002). "Studies in Euphorbiaceae A.L.Juss. sens. lat. 3. A revision of Bertya Planch. (Ricinocarpeae Mull.Arg., Bertyinae Mull.Arg.)". Austrobaileya. 6 (2): 235–238. Retrieved 16 May 2025.
3. Halford, David A. Moon, Christina D.; Orchard, Anthony E. (eds.). "Bertya tasmanica". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 19 May 2025.
4. Murray, Louisa. "Bertya tasmanica". Royal Botanic Garden, Sydney. Retrieved 20 May 2025.
5. "Ricinocarpos tasmanicus". Australian Plant Name Index. Retrieved 19 May 2025.
6. Sonder, Otto W.; von Mueller, Ferdinand (1857). "Plantae Muellerianae - Euphorbiaceae". Linnaea: ein Journal für die Botanik in ihrem ganzen Umfange, oder Beiträge zur Pflanzenkunde. 28 (5): 562. Retrieved 19 May 2025.
7. "Bertya tasmanica". Australian Plant Name Index. Retrieved 19 May 2025.
8. Muller, Johannes Mueller (1865). "Euphorbiaceae: Vorläufige mittheilungen aus dem für DeCandolle's Prodromus bestimmten Manuscript über diese Familie". Linnaea: ein Journal für die Botanik in ihrem ganzen Umfange, oder Beiträge zur Pflanzenkunde. 34: 63. Retrieved 19 May 2025.
9. "Bertya tasmanica subsp. tasmanica". Australian Plant Census. Retrieved 19 May 2025.
10. Halford, David A. "Bertya tasmanica subsp. tasmanica". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 19 May 2025.
11. "Bertya tasmanica subsp. vestita". Australian Plant Census. Retrieved 19 May 2025.
12. Halford, David A. "Bertya tasmanica subsp. vestita". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 19 May 2025.
13. "Bertya tasmanica ssp. vestita". Seeds of South Australia. Retrieved 20 May 2025.
14. Ohlsen, Daniel; Stajsic, Val. "Bertya tasmanica supsp. vestita". Royal Botanic Gardens Victoria. Retrieved 20 May 2025.
15. "Bertya tasmanica subsp. tasmanica". Australian Government Department of Climate Change, Energy, the Environment and Water. Retrieved 20 May 2025.
16. "Bertya tasmanica subsp. tasmanica". Tasmanian Government Department of Natural Resources and Environment Tasmania. Retrieved 20 May 2025.