Seeds of South Australia
Cyperus gilesii (Cyperaceae)
Giles' Flat-sedge
List of species for Cyperus
Display more images
Click on an image to enlarge it
Seed collecting:
January to December
Herbarium regions:
North Western, Lake Eyre, Gairdner-Torrens, Flinders Ranges, Eastern
NRM regions:
Alinytjara Wilurara, South Australian Arid Lands
IBRA regions
Gawler Lakes (GAW03)Gawler
 Rare   (IUCN: RA d(ii))   [rocky hills]
Arcoona Plateau (GAW04) 
 Rare   (IUCN: RA d(ii))
Kingoonya (GAW05) 
 Rare   (IUCN: RA d(ii))
Bimbowrie (BHC05)Broken Hill Complex
 Endangered   (IUCN: EN D)   [<20 plants]
Breakaways (STP01)Stony Plains
 Near Threatened
Oodnadatta (STP02) 
 Near Threatened
Macumba (STP05) 
 Near Threatened
Witjira (STP06) 
 Near Threatened
Baltana (STP07) 
 Near Threatened
Sturt Stony Desert (CHC02)Channel Country
 Near Threatened
Coongie (CHC06) 
 Near Threatened   [undercollected ]
Lake Pure (CHC07) 
 Rare   (IUCN: RA d(I,ii))
Everard Block (CER03)Central Ranges
 Rare   (IUCN: RA d(i,ii))
IBRA regions
3 of 8 subregionsGawlerRare
Bimbowrie (BHC05)Broken Hill ComplexEndangered
  (IUCN: EN D)   [<20 plants]
5 of 7 subregionsStony PlainsNear Threatened
3 of 4 subregionsChannel CountryNear Threatened
, Rare
Everard Block (CER03)Central RangesRare
  (IUCN: RA d(i,ii))
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. Gilesii named after William Ernest Powell Giles (1835-1897), an Australian explorer who led five major expeditions in central Australia.
Found in the north and north-east part of South Australia growing in ephemerally wet situations such as inland stream banks. Also found in Western Australia, Northern territory, Queensland and New South Wales.
Native. Common in South Australia. Rare in Western Australia. Common in the other States.
Plant description:
Slender annual sedge to 30 cm high. Stems usually tufted, erect, slender; trigonous, smooth but prominently striate. Leaves shorter than the stems, 1-4.5 mm wide, margins sparsely scabrous; bracts 2-4, leaf-like, the lower longer or much longer than the inflorescence. Flower-spike a simple umbel or reduced to a head, the rays up to 5 in number; slender but rigid, to 6 cm long; spikelets approximate but not quite digitate, few to several on each ray; bright-brown, chestnut, or golden-brown, 15-30-flowered; lanceolate to linear, rather acute, very flat, c. 10-30 mm long, 2.5-4.5 mm wide; rhachilla wingless or nearly so; glumes rather dense but soon spreading and their margins inrolled; 4-5 mm long, prominently nerved with a finally recurved mucro to 1 mm long; style 3-branched. Flowering between September and April.
Fruit type:
Flat, golden brown fruit-head in dense clusters.
Seed type:
Brown long oblong seed to 5 mm long and 1 mm wide.
Embryo type:
Seed collecting:
Collect fruits by picking off the mature heads, those turning golden 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. 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 two collections, the seed viability was high, ranging from 90% to 95%.
Seeds stored:
LocationNo. of seeds
(weight grams)
of plants
Collection number
Collection location
% ViabilityStorage
BGA10900 (8.43 g)50+12-Aug-2010TST961
Lake Eyre
BGA2700 (0.93 g)2011-Aug-2010DJD1848
Lake Eyre
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:
DateResultT0T50Pre-treatment | Germination medium | Incubator: Photoperiod / Thermoperiod
Jun-1777%77 30% hydrogen peroxide for 10 min, water rinse, 500 mg/L gibberellic acid for 44 h;
1% agar;
Incubated under summer conditions
1% agar;
Incubated under summer conditions
Jun-1733%14NA 30% hydrogen peroxide for 10 min, water rinse, 500 mg/L gibberellic acid for 44 h;
1% agar;
Incubated under spring/autumn conditions
1% agar;
Incubated under spring/autumn conditions
1% agar;
Incubated under winter conditions
Jun-173%28NA 30% hydrogen peroxide for 10 min, water rinse, 500 mg/L gibberellic acid for 44 h;
1% agar;
Incubated under winter conditions
Result: Maximum percentage of germination observed.
T0: Number of days before first germinant observed.
T50: Number of days to achieve 50% germination.
Pre-treatment: The initial treatment that the seeds received prior to placement on germination media.
Germination medium: The substrate that seeds were placed on for the duration of the germination experiment.
Incubator conditions:
Photoperiod: The duration of light exposure that the seeds were subject to during a 24 hour period.
Thermoperiod: The constant or diurnal temperatures that seeds were subject to during a 24 hour period.
Winter conditions: 15°C 20 h (3am→11pm); 5°C 4 h (11pm→3am) / 10 h light (8am→6pm); 14 h dark (6pm→8am)
Spring/Autumn conditions: 22°C 12 h (8am→8pm); 10°C 12 h (8pm→8am) / 12 h light (8am→8pm); 12 h dark (8pm→8am)
Summer conditions: 30°C 14 h (6am→8pm); 15°C 10 h (8pm→6am) / 14 h light (6am→8pm); 10 h dark (8pm→6am)