Seeds of South Australia
Acianthus pusillus (Orchidaceae)
Small Mosquito Orchid
List of species for Acianthus
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Seed collecting:
August to October
Herbarium regions:
Flinders Ranges, 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
Mount Gambier (SVP02)Southern Volcanic Plain
 Least Concern
Bridgewater (NCP01)Naracoorte Coastal Plain
 Least Concern
Glenelg Plain (NCP02) 
 Least Concern
Lucindale (NCP03) 
 Least Concern
Tintinara (NCP04) 
 Least Concern
Kangaroo Island (KAN01)Kanmantoo
 Least Concern
Fleurieu (KAN02) 
 Least Concern
Mount Lofty Ranges (FLB01)Flinders Lofty Block
 Least Concern
Broughton (FLB02) 
 Least Concern   (Probable Decline)   [Highly fragmented, declining.]
Southern Flinders (FLB04) 
 Least Concern   (Probable Decline)   [Declining. Climate related.]
Southern Yorke (EYB01)Eyre Yorke Block
 Least Concern   (Probable Decline)
St Vincent (EYB02) 
 Rare   (IUCN: RA a)   (Definite Decline)   [Small population. Definite decrease.]
Eyre Hills (EYB03) 
 Least Concern
Talia (EYB04) 
 Least Concern
Eyre Mallee (EYB05) 
 Rare   (IUCN: RA d(ii))   (Probable Decline)   [needs rainfall]
Murray Mallee (MDD02)Murray Darling Depression
 Rare   (IUCN: RA bd(ii))   (Probable Decline)   [lack of flowering; lack of rainfall]
Murray Lakes and Coorong (MDD03) 
 Least Concern
Lowan Mallee (MDD04) 
 Rare   (IUCN: RA bd(ii))   (Probable Decline)   [lack of flowering; lack of rainfall]
Wimmera (MDD05) 
 Rare   (IUCN: RA d(ii))   (Probable Decline)   [limited habitat]
Gawler Volcanics (GAW02)Gawler
 Vulnerable   (IUCN: VU D2)   (Probable Decline)   [occurs on sand]
IBRA regions
Mount Gambier (SVP02)Southern Volcanic PlainLeast Concern
4 of 4 subregionsNaracoorte Coastal PlainLeast Concern
2 of 2 subregionsKanmantooLeast Concern
3 of 6 subregionsFlinders Lofty BlockLeast Concern
5 of 5 subregionsEyre Yorke BlockLeast Concern
, Rare
4 of 6 subregionsMurray Darling DepressionLeast Concern
, Rare
Gawler Volcanics (GAW02)GawlerVulnerable
  (IUCN: VU D2)   (Probable Decline)   [occurs on sand]
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 Acianthus]
Name derivation:
Acianthus from the Greek 'akis' meaning a point or needle and 'anthos' meaning flower, referring to the pointed sepals. Pusillus from Latin meaning very small, may refer to the small size of the flowers..
Found in the southern part of South Australia, growing in damp, shady places in a variety of soils and habitats. Also found in Queensland, New South Wales, Victoria and Tasmania. 
Native. Common in South Australia. Uncommon in Queensland. Common in the other States.
Plant description:
Flowering plant to 12cm high. Leaf heart-shaped to 30 mm long and 25 mm wide, green above, reddish-purple (rarely greenish) beneath. Leaf margins entire or sometimes shallowly lobed. Flowers from 1-18, translucent green, or pinkish with reddish veins and spots; labellum green to reddish-purple. Dorsal sepal ends in a prominent slender point; lateral sepals are narrow, acuminate and sometimes crossed and gland tipped. The labellum, ovate-lanceolate, to 5mm long, has two basal glands and a short pointed apex. The column is curved forward, with a small concave end. Flowering between May and August.
Fruit type:
Brown papery ellipsoid capsule, reddish when immature.
Seed collecting:
Collect fat capsules as they start to dry and turn brown. Pods will split and release the seeds quickly and will require monitoring. To increase the chances of collecting mature pods, it is recommended that a small breathable bag (ie. Organza bags) be used to enclose the developing capsules.
Seed cleaning:
Place the capsules in a container that will hold fine seeds and leave to dry for a few weeks or until the capsule split. Then carefully hold the capsule and tap it gently to release the 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 or in liquid nitrogen.