Seeds of South Australia
Cyperus castaneus (Cyperaceae)
Chestnut Flat-sedge
List of species for Cyperus
Click on an image to enlarge it
Herbarium region:
North Western
NRM region:
Alinytjara Wilurara
IBRA region
Tallaringa (GVD05)Great Victoria Desert
 Vulnerable   (IUCN: VU D2)   [ephemeral; highly localised; lack of records/data]
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. Castaneus is the Latin name for chestnut; referring tom the chestnut-colour of the glumes.
Distribution:
Few records from the far northern part of South Australia,  growing in ephemerally wet  areas such as claypans and wet depression on open sandy soils. Also found in Western Australia, Northern Territory, Queensland and New South Wales (and tropical Asia and Bangladesh, Myanmar, Sri Lanka, India and Nepal).
Status:
Native. Rare in South Australia. Uncommon in New South Wales. Common in the other states.
Plant description:
Small tuft grass-like annual sedge 70 cm high. Culms trigonous, smooth, to 10 cm high and 1 mm diameter. Leaves shorter than culms. Inflorescence simple, with 1–4 branches to 3 cm long arranged in clusters to 15 mm diameter. Spikelets flattened, to 20 mm long and 2 mm wide. Glumes emarginate, with sides 1-nerved near midrib, to 1.4 mm long and 0.8 mm wide, red-brown to very dark red-brown. Flowering between February and April as water subside.
Fruit type:
Red-brown fruit-head in spikey clusters at the terminal of stems.
Seed type:
Brown narrow ovoid seed to 0.7 mm long and 0.3 mm wide, covered with a thin shiny tuberculate transparent layer.
Embryo type:
Capitate.
Seed collecting:
Collect fruits by picking off the mature heads, those turning red-brown colour 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.