Plants of
South Australia
Roepera ammophila
Zygophyllaceae
Sand Twinleaf
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Regional Species Conservation Assessments per IBRA subregion.
Least concern
Near threatened
Rare
Vulnerable
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Extinct
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Adelaide
Arkaroola
Ceduna
Coober Pedy
Hawker
Innamincka
Marla
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Oodnadatta
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Wudinna
Keith
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Botanical art

Kath Alcock paintings: 4

Prior names

Zygophyllum ammophilum

Zygophyllum billardierei, partly

Zygophyllum billardierei var. ammophilum, partly

Etymology

Roepera (formally Zygophyllum which is from the Greek 'zygon' meaning pair and 'phyllon' meaning leaf; referring to the pair of leaflets making up each leaf) is named after Johannes August Christian Roeper (1801 -1885), a German botanist and physician. Ammophila from the Latin 'ammo' meaning sand and 'philus' meaning loving; referring to its sandy habitat.

Distribution and status

Found in the eastern part of South Australia, growing on sand and sandy loams but also on heavier clay soils. Also found in New South Wales and Victoria. Native. Common in South Australia. Common in the other states.
Herbarium region: Murray
NRM region: South Australian Murray-Darling Basin
AVH map: SA distribution map (external link)

Plant description

Erect or ascending, much-branched annual herb 30 cm high. Leaves to 45 mm long with leaflets articulate at base, linear-oblong, to 25 mm long and 3 mm wide, fleshy, apex truncate or sometimes rounded or emarginate. Flowers white or yellow with 4 sepals, 4 petals and 4 stamens. This species is similar to Roepera simile which have 8 stamens and only 1 or 2 seeds per cell. Flowering between August and November. Fruits are 4-angled capsule to 7 mm long, drooping, truncate at apex with a short point with 3 or 4 seeds per cell. Seeds are dark brown, semi-flat ovoid to 3 mm long and 1.5 mm wide, with a reticulated or rugose surface. Seed embryo type is spatulate fully developed.

Seed collection and propagation

Collect seeds between October and January. Collect semi-dried and dried capsules by running your hands through the stems of the plant. Mature fruits will come off easily and will have a hard and dark seed inside each segment. Place the capsules in a tray and leave to dry for 1 to 2 weeks, depending on how green the fruit is. Then rub the dried capsules to dislodge the seeds. Use a sieve to remove the unwanted material. Store the seeds with a desiccant such as dried silica beads or dry rice, in an air tight container in a cool and dry place. Seed viability is usually high.

Seeds stored:
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LocationNo. of seeds
(weight grams)		Number
of plants		Date
collected		Collection number
Collection location		Date
stored		% ViabilityStorage
temperature
BGA 
MSB		6,400 (7.12 g)
6,400 (7.12 g)		30+8-Nov-2016DJD3568
Murray		1-Nov-2017100%-18°C
Location: BGA — the seeds are stored at the Adelaide Botanic Gardens, MSB — the seeds are stored at the Millennium Seed Bank, Kew, England.
Number of plants: This is the number of plants from which the seeds were collected.
Collection location: The Herbarium of South Australia's region name.
% Viability: Percentage of filled healthy seeds determined by a cut test or x-ray.
Germination table:
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We acknowledge the contributions of the South Australian Seed Conservation Centre, the Botanic Gardens of South Australia, and the Department for Environment and Water.