Seeds of South Australia
Cyperus iria (Cyperaceae)
Rice Flat-sedge
List of species for Cyperus
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Seed collecting:
March to August
Herbarium regions:
North Western, Lake Eyre, Gairdner-Torrens
NRM region:
South Australian Arid Lands
IBRA regions
Arcoona Plateau (GAW04)Gawler
 Rare   (IUCN: RA d(ii))   [southern limit]
Kingoonya (GAW05) 
 Rare   (IUCN: RA d(ii))   [southern limit]
Roxby (GAW07) 
 Near Threatened
Commonwealth Hill (GAW08) 
 Near Threatened
Kintore (GVD04)Great Victoria Desert
 Near Threatened
Tallaringa (GVD05) 
 Rare   (IUCN: RA d(i,ii))   [edge of range]
Dieri (SSD03)Simpson Strzelecki Dunefields
 Near Threatened
Strzelecki Desert (SSD05) 
 Least Concern
Breakaways (STP01)Stony Plains
 Least Concern
Oodnadatta (STP02) 
 Least Concern
Murnpeowie (STP03) 
 Near Threatened
Macumba (STP05) 
 Least Concern
Witjira (STP06) 
 Least Concern
Baltana (STP07) 
 Least Concern
Sturt Stony Desert (CHC02)Channel Country
 Least Concern
Coongie (CHC06) 
 Least Concern
Lake Pure (CHC07) 
 Least Concern
Everard Block (CER03)Central Ranges
 Near Threatened
Pedirka (FIN04)Finke
 Near Threatened
IBRA regions
4 of 8 subregionsGawlerNear Threatened
, Rare
2 of 4 subregionsGreat Victoria DesertNear Threatened
, Rare
2 of 4 subregionsSimpson Strzelecki DunefieldsLeast Concern
, Near Threatened
6 of 7 subregionsStony PlainsLeast Concern
, Near Threatened
3 of 4 subregionsChannel CountryLeast Concern
Everard Block (CER03)Central RangesNear Threatened
Pedirka (FIN04)FinkeNear Threatened
RSCA map:
Regional Species Conservation Assessments per IBRA subregion. Please click the thumbnail map.
AVH map:
Australian distribution map (external link)
SA Census:
Census of South Australian plants (external link)     [genus Cyperus]
Name derivation:
Cyperus from the Latin 'cyperos' and derived from the Greek 'kypeiros', an ancient Greek name used by Homer and Theophrastus for several plants of this genus.
Found in  northern South Australia growing in ephemerally wet, open, often disturbed, situations. Also found in Western Australia, Northern Territory, Queensland, New South Wales and other parts of the world.
Native. Common in South Australia. Common in the other States.
Plant description:
Annual sedge to 50 cm high. Stems slender to setaceous; triquetrous, solitary or tufted. Leaves narrow, flaccid, shorter or longer than the stems; bracts 2-5, spreading, the lower longer than the inflorescence. Flower-spike an umbel; very variable, simple or compound or loose, or in small specimens reduced to a small cluster; spikelets in well-developed inflorescences distinctly spicately arranged; bright-brown or golden to greenish, linear, 6-30-flowered, 4-20 mm long, 1.5-2.5 mm wide; rhachilla not winged; glumes somewhat distant, very broad and obtuse, obovate in profile, with a 3-5-nerved back and practically nerveless sides; 1.25-1.75 mm long; style 3-branched. Flowering between January and June.
Fruit type:
Flat, brown fruit-head in loose clusters.
Seed type:
Dark brown to black  ovoid triangular seed to 1.3 mm long and 0.8 mm wide, with fine reticulate surface and covered with a thin shiny transparent layer.
Embryo type:
Seed collecting:
Collect fruits by picking off the mature heads, those turning brown and come-off easily.
Seed cleaning:
Place the heads in a tray and leave to dry for one to two weeks. Then rub the heads with a rubber bung to dislodge the seeds. Use a sieve to separate any unwanted material. Be careful, as the seeds are very small. Seeds are brown, ovoid and hard. 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:
From one collection, the seed viability was high, at 100%.
Seeds stored:
LocationNo. of seeds
(weight grams)
of plants
Collection number
Collection location
% ViabilityStorage
BGA100000 (21.45 g)5014-Mar-2007RJB70921
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.