Seeds of South Australia
Tetrarrhena acuminata (Gramineae)
Pointed Rice-grass
List of species for Tetrarrhena
Display more images
Click on an image to enlarge it
Seed collecting:
November to March
Herbarium region:
South Eastern
NRM region:
South East
IBRA regions
Mount Gambier (SVP02)Southern Volcanic Plain
 Endangered   (IUCN: EN B2ab(i,ii,iii))   (Probable Decline)   [habitat loss a threat]
Bridgewater (NCP01)Naracoorte Coastal Plain
 Endangered   (IUCN: EN B2ab(i,ii,iii))   (Probable Decline)   [habitat loss a threat]
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 Tetrarrhena]
Name derivation:
Tetrarrhena from the Greek 'tetra' meaning four and 'arrhen' meaning male, referring to the 4 anthers which is unusual in the Poaceae. Acuminata from the Latin 'acumen' meaning sharp point and '-ata' meaning possessing, referring to the upper sterile lemma which are drawn out to a long, narrow point.
Distribution:
Found only in the lower South-east in South Australia, growing in open aspect in wet heath. Also found in New South Wales, Victoria and Tasmania.
Status:
Native. Very rare in South Australia. Rare in New South Wales. Common in the other states.
Plant description:
Rhizomatous perennial grass with decumbent or weakly ascending stems to 1 m long. Leaves distichous, glabrous or minutely scabrous with flat blade to 70 mm long and 5 mm wide, ligule membranous, irregularly toothed, 0.8–2 mm long. Inflorescence spike-like raceme to 5 cm long. Glumes to 3 mm long, the lower slightly shorter than upper, both smooth and glabrous. Lower sterile lemma shorter than upper, acute or obtuse, upper sterile lemma acute to acuminate and sometimes shortly mucronate with 5–7-nerved, fertile lemma slightly shorter than upper sterile lemma, often minutely mucronate, scabrous along keel. Flowering between September and February.
Fruit type:
Short pale brown spike.
Embryo type:
Lateral.
Seed collecting:
Use hands to gently strip seeds off the mature seed spike that are turning straw colour. Mature seeds will come off easily. Alternatively, you can break off the whole seed spike.
Seed cleaning:
Place the seeds/spike in a tray and leave to dry for two weeks. No further cleaning is required if only seed collected. If seed spikes collected, use hand to strip off the mature seeds. 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.