Seeds of South Australia
Acanthocladium dockeri (Compositae)
Spiny daisy
List of species for Acanthocladium
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Seed collecting:
November to December
Herbarium regions:
Northern Lofty, Murray
NRM regions:
Northern and Yorke, South Australian Murray-Darling Basin
IBRA regions
Broughton (FLB02)Flinders Lofty Block
 Critically Endangered   (IUCN: CR D)   [Four clonal populations, remaining stable.]
St Vincent (EYB02)Eyre Yorke Block
 Critically Endangered   (IUCN: CR D)   [One clonal populations, currently stable.]
Murray Scroll Belt (RIV06)Riverina
 Regionally Extinct   [presumed extinct]
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 Acanthocladium]
Name derivation:
Acanthocladium from the Greek 'akantha' meaning thorn and 'kladion', from 'klados' meaning a branch, referring to the spine at the end of the branchlets. Dockeri named after the Reverend Joseph Docker (1793-1865), who supported and promoted the Burke and Wills expedition.
Found mainly road reserves in the mid-north region of South Australia, growing in grassland or low grassy shrubland. Originally collected from the Riverland but 'presumed extinct' there. Presumed to be extinct in New South Wales. Now considered endemic to South Australia.
Native. Very rare in South Australia.
Plant description:
Many branching perennial shrub to 50 cm high, covered in spines and white hairs that make the plant appear grey. Flower is a small yellow, rayless daisy at the tip, appearing in winter and spring. Most of the flowers are sterile and so the plant  reproduces mainly by suckering.
Fruit type:
Small pale yellow daisy-head.
Seed type:
Small cylindrical brown seeds to 3 mm long and 0.5 mm wide, covered in small transparent warts.
Embryo type:
Spatulate fully developed.
Seed collecting:
This species does not produce a lot of viable seeds. It is usually clonal but some populations do produce seeds. Collect heads that are brown.
Seed cleaning:
Place the heads in a tray for a week to dry. Then rub the heads gently with your hands to dislodge the seeds. Viable seeds will be round 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:
Very low seed viability, less than 5% with most plants producing no viable seed.
Seed germination:
Seeds are non-dormant, viable seed should germinate readily.
Seeds stored:
LocationNo. of seeds
(weight grams)
of plants
Collection number
Collection location
% ViabilityStorage
190 (0.08 g)
780 (0.32 g)
Flinders Ranges
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-08100%14 d14 d
filter paper over moist sand;
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)