Seeds of South Australia
Acacia paradoxa (Leguminosae)
Kangaroo Thorn
List of species for Acacia
Display more images
Click on an image to enlarge it
Seed collecting:
October to January
Herbarium regions:
Flinders Ranges, Eastern, Eyre Peninsula, Northern Lofty, Murray, Yorke Peninsula, Southern Lofty, Kangaroo Island, South Eastern
NRM regions:
Adelaide and Mount Lofty Ranges, Eyre Peninsula, Kangaroo Island, Northern and Yorke, South Australian Arid Lands, South Australian Murray-Darling Basin, South East
IBRA regions
SUMMARY
Bridgewater (NCP01)Naracoorte Coastal Plain
 Least Concern   [question if introduced]
Lucindale (NCP03) 
 Least Concern   (Probable Increase)   [spreading]
Tintinara (NCP04) 
 Rare   (IUCN: RA d(i,ii))   [Mt Monster]
Kangaroo Island (KAN01)Kanmantoo
 Least Concern
Fleurieu (KAN02) 
 Least Concern
Mount Lofty Ranges (FLB01)Flinders Lofty Block
 Least Concern
Broughton (FLB02) 
 Least Concern
Olary Spur (FLB03) 
 Least Concern
Southern Flinders (FLB04) 
 Least Concern
Central Flinders (FLB06) 
 Rare   (IUCN: RA d(ii))   [northern edge of range]
Southern Yorke (EYB01)Eyre Yorke Block
 Least Concern   [Is it native or weedy]
St Vincent (EYB02) 
 Least Concern
Eyre Hills (EYB03) 
 Least Concern
Talia (EYB04) 
 Least Concern
Murray Mallee (MDD02)Murray Darling Depression
 Rare   (IUCN: RA d(ii))   (Probable Decline)   [edge of range; climatge change a threat]
Murray Lakes and Coorong (MDD03) 
 Least Concern   [edge of range]
Lowan Mallee (MDD04) 
 Least Concern   (Probable Increase)   [farmers say increasing]
Wimmera (MDD05) 
 Rare   (IUCN: RA d(i,ii))   [in Frances cemetary]
IBRA regions
DISPLAY ALL
3 of 4 subregionsNaracoorte Coastal PlainLeast Concern
, Rare
2 of 2 subregionsKanmantooLeast Concern
5 of 6 subregionsFlinders Lofty BlockLeast Concern
, Rare
4 of 5 subregionsEyre Yorke BlockLeast Concern
4 of 6 subregionsMurray Darling DepressionLeast Concern
, Rare
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 Acacia]
Name derivation:
Acacia from the Greek 'akakia' and derived from 'ake' or 'akis' meaning a sharp point or thorn and 'akazo' meaning to sharpen. Dioscorides, the Greek physician and botanist used the word in the 1st century AD for the Egyptian thorn tree, Acacia arabicaParadoxa from the Greek 'para' meaning near and 'doxa' meaning glory, splendour, may refer to this unattractive and thorny shrub being a showy plant when in full bloom. 
Distribution:
Found in the southern part of South Australia, growing on hard alkaline red duplex, hard acidic or neutral yellow duplex and shallow calcareous loamy soil in woodland, open forest and open scrub vegetation. Also found in Queensland, New South Wales and Victoria. Introduced in Western Australia and Tasmania.
Status:
Native. Common in South Australia. Uncommon in Queensland. Common in New South Wales and Victoria. Naturalised in Western Australia and Tasmania.
Plant description:
Straggly to dense shrub or tree to 4 m high with branches often arched down with ribbed branchlets. Leaves erect, asymmetric, usually lanceolate, sometimes narrowly oblong-elliptic to 30 mm long and 7 mm wide; glabrous to sparsely hairy, abaxial margin usually undulate, acute or obtuse, with a pungent mucro; midrib usually off-centre, stipules spiny. Flower-spike axillary, singular with globular, golden flower-heads. Flowering between August and October.
Fruit type:
Dark brown linear to narrowly oblong pod to 60 mm long and 5 mm wide, densely hairy.
Seed type:
Hard, dark brown to black oblong seed to 6 mm long and 3 mm wide.
Embryo type:
Investing.
Seed collecting:
Collect mature pods that are turning brown with hard, dark seeds inside.
Seed cleaning:
Place the pods in a tray and leave to dry for 1-2 weeks or until the pods begin to split. Then rub the dried pods 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 germination:
This species has physical dormancy that needs to be overcome for the seed to germinate (e.g. nicking or softening the seed coat).
Germination table:
DateResultT0T50Pre-treatment | Germination medium | Incubator: Photoperiod / Thermoperiod
March 201590%14d21d seed coat nicked
1% water agar
Incubated under spring/autumn conditions
March 201582%14d21d seed coat nicked
1% water agar
Incubated under winter conditions
March 201528%14dNA None
1% water agar
Incubated under spring/autumn conditions
March 201522%14dNA none
1% water 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)