Prior names
Thelymitra aristata (Adelaide Hills)
Common names
Scented Sun-orchid
Great Sun-orchid
Etymology
Thelymitra from Greek 'thelys' meaning a bishop and 'mitra' meaning a headwear, hat, hence a bishop's mitre, referring to the sometimes plumed or decorated wings of the column, which is usually produced behind and over the anther in a hood-like projection. Grandiflora referring to the species large-flower, the largest of any sun-orchid flowers in South Australia.
Distribution and status
Endemic to South Australia and found in the Flinders Ranges, Mount Lofty Ranges and Kangaroo Island, growing on ridges in dry rocky heathland and in well drained soils in woodland. Native. Rare in South Australia.
Herbarium regions: Flinders Ranges, Eyre Peninsula, Northern Lofty, Southern Lofty, Kangaroo Island, Green Adelaide
NRM regions: Adelaide and Mount Lofty Ranges, Eyre Peninsula, Kangaroo Island, Northern and Yorke, South Australian Arid Lands
AVH map: SA distribution map (external link)
Plant description
Terrestrial orchid growing to 100 cm tall in flower, with large, broad-lanceolate leaf to 30 cm long. Inflorescence a large glaucous spike with pale to deep blue, lilac or pinkish-mauve flowers to 40 mm across. Flowering between September and November. Fruits are brown papery ellipsoid capsule. Seeds are very small brown ellipsoid seed with an ovoid translucent brown mesh-like covering.
Seed collection and propagation
Collect seeds between November and December. 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. 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, refrigerator or in liquid nitrogen. Seed germination in Thelymitra species is difficult in the absence of symbiotic mycorrhizal fungi.
Fire response
Obligate re-spouter and re-seeder.
Longevity: ?? years
Time to flowering: ?? years
Recovery work
In 2020-2021 this species was assessed post-fire in 1 year old fire scars. A total of 296,200 seeds have been collected & banked for a population outside the 2020 fire scar. Further populations will be assessed and seeds collected on Kangaroo Island in 2021–2022. Germination screening testing the response to fire cues will be undertaken in 2021. This project was supported by the World Wildlife Fund program.
Location | No. of seeds (weight grams) | Number of plants | Date collected | Collection number Collection location | Date stored | % Viability | Storage temperature |
---|---|---|---|---|---|---|---|
BGA | 100,000 (0.078 g) | 1 | 17-Nov-2011 | K. Brewer Southern Lofty | 1-Nov-2016 | 85% | -80°C |
BGA MSB | 500,000 500,000 | 5 | 3-Dec-2007 | RJB76042 Southern Lofty | 1-Nov-2016 | N/C | -80°C |
BGA | 269,000 (0.21 g) | 29-Nov-2016 | Alligator Gorge Flinders Ranges | 1-Nov-2017 | N/C | -18°C, -80°C | |
BGA | 84,000 (0.066 g) | 3 | 14-Nov-2019 | TST1436 Southern Lofty | 24-Jun-2020 | N/C | -18°C |
BGA | 423,000 (0.33 g) | 4 | 14-Nov-2019 | Goondooloo, Deep Creek CP Southern Lofty | 24-Jun-2020 | N/C | -18°C, -80°C |
BGA | 296,200 (0.230 g) | 10 | 24-Nov-2020 | DJD3945 Southern Lofty | 28-Jun-2021 | N/C | -18°C, -80°C |
BGA | 3,711,600 (2.894 g) | 12 | 9-Dec-2021 | TST1483 Southern Lofty | 10-Aug-2022 | N/C | -18°C, -80°C |
BGA | 444,785 (0.347 g) | 6 | 30-Nov-2021 | BKB20 Kangaroo Island | 10-Aug-2022 | N/C | -18°C, -80°C |