Seeds of South Australia
Acianthus caudatus (Orchidaceae)
Mayfly orchid
List of species for Acianthus
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Seed collecting:
July to September
Herbarium regions:
Eyre Peninsula, Northern Lofty, Murray, Yorke Peninsula, Southern Lofty, Kangaroo Island, South Eastern
NRM regions:
Adelaide and Mount Lofty Ranges, Kangaroo Island
IBRA regions
Mount Gambier (SVP02)Southern Volcanic Plain
 Endangered   (IUCN: EN B2ab(i,ii,iii))   (Probable Decline)   [loss of habitat]
Glenelg Plain (NCP02)Naracoorte Coastal Plain
 Rare   (IUCN: RA d(ii))   [no records, newly discovered here - CathyHouston]
Lucindale (NCP03) 
 Rare   (IUCN: RA d(ii))   [edge of range]
Tintinara (NCP04) 
 Rare   (IUCN: RA d(i,ii))   (Probable Decline)   [edge of range]
Kangaroo Island (KAN01)Kanmantoo
 Least Concern
Fleurieu (KAN02) 
 Least Concern
Mount Lofty Ranges (FLB01)Flinders Lofty Block
 Least Concern
Southern Flinders (FLB04) 
 Regionally Extinct   [Not recorded since 1906, now extinct from region.]
Southern Yorke (EYB01)Eyre Yorke Block
 Critically Endangered   (IUCN: CR D)   [Two small patches, less than 50 individuals. Newly discovered, data deficient.]
Eyre Hills (EYB03) 
 Critically Endangered   (IUCN: CR D)   [One large popn near Mikara. CR because clonal]
Murray Mallee (MDD02)Murray Darling Depression
 Rare   (IUCN: RA d(i,ii))   [near Finniss, edge of range, lack of suitable habitat]
Murray Lakes and Coorong (MDD03) 
 Rare   (IUCN: RA d(i,ii))   (Probable Decline)   [few records; seen less & less; in Potters Scrub; limited habitat]
Lowan Mallee (MDD04) 
 Rare   (IUCN: RA d(i,ii))   [no records, near Mundulla]
IBRA regions
Mount Gambier (SVP02)Southern Volcanic PlainEndangered
  (IUCN: EN B2ab(i,ii,iii))   (Probable Decline)   [loss of habitat]
3 of 4 subregionsNaracoorte Coastal PlainRare
2 of 2 subregionsKanmantooLeast Concern
2 of 6 subregionsFlinders Lofty BlockLeast Concern
, Regionally Extinct
2 of 5 subregionsEyre Yorke BlockCritically Endangered
3 of 6 subregionsMurray Darling DepressionRare
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. Caudatus from the Latin 'cauda' meaning tail, referring to the long 'tail-like' dorsal sepals.
Found mainly on Kangaroo Island and the southern Mount Lofty Ranges in South Australia, with scattered and isolated records from the S of  Eyre and Yorke Peninsulas, southern Flinders Ranges and the South-east; growing in clay or sandy soils, in shaded places in open woodland. Also found in Queensland, New South Wales, Victoria and Tasmania.
Native. Uncommon in South Australia. rare in Queensland. Common in the other States.
Plant description:
Flowering plant to 14 cm tall. Leaf heart-shaped to 33 mm long and 30 mm wide, green above, reddish-purple beneath; margins wavy and clasping the reddish stem just above the ground. Flowers from 1–6, dark purplish, often with musty odour. Dorsal sepal to 45 mm long, tapering to a fine point, lateral sepal shorter to 25 mm long, tapering to fine points curving upwards at tips. Flowering between September and October.
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 capsules 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.