Corunastylis nudiscapa belongs to a group of orchids commonly known as midge orchids. Species of Corunastylis are mostly pollinated by small vinegar flies (drosophilids) attracted to the flowers by fruit perfumes and hairy segments. Corunastylis nudiscapa has been recorded from only two locations in Tasmania - Oyster Cove and South Hobart. The species occurs in open forests and woodlands dominated by Eucalyptus tenuiramis (silver peppermint) or Eucalyptus obliqua (stringybark), with a heathy ground layer, with a total population of about 250 plants. There has been extensive survey of potential habitat without success, and the likelihood of discovery of new populations is considered low. Threats to the species include clearing of habitat and damage to individual plants during track and road maintenance, inappropriate weed control operations, and inappropriate fire regimes.
- Important: Is this species in your area? Do you need a permit? Ensure you’ve covered all the issues by checking the Planning Ahead page.
- Important: Different threatened species may have different requirements. For any activity you are considering, read the Activity Advice pages for background information and important advice about managing around the needs of multiple threatened species.
- ‘Habitat’ refers to both known habitat for the species (i.e. in or near habitat where the species has been recorded) and potential habitat (i.e. areas of habitat with appropriate characteristics for the species and within the species potential range which have not yet been adequately surveyed).
- If in doubt about whether a site represents potential habitat for this species, contact the Threatened Species Section for further advice.
- The known range of the bare midge-orchid include the two recorded localities at Oyster Cove and South Hobart (see distribution map, above). The potential range of the species covers all of south-east Tasmania. However, note that there has been extensive survey of other sites with suitable habitat without success, and the likelihood of discovery of new locations for the species outside the current known range is considered low.
- Habitat for the bare midge-orchid corresponds to the following vegetation types in the DPIPWE Bushcare Toolkit: Grassy/heathy woodland and forest, Heathy woodland and forest, and Shrubby forest (all also known as dry sclerophyll). See Eucalypt Bush in the Bushcare Toolkit for more information on managing these vegatation types.
- Habitat characteristics for the bare midge-orchid includes the following: open forests and woodlands dominated by Eucalyptus tenuiramis (silver peppermint) or Eucalyptus obliqua (stringybark), with a heathy ground layer of varying density; associated shrubs may include Pultenaea gunnii var. baeckioides (delicate golden bushpea), Pultenaea juniperina (prickly beauty), Aotus ericoides (golden pea), Acacia myrtifolia (redstem wattle), Epacris impressa (common heath), Tetratheca labillardierei (glandular pinkbells), Acacia terminalis (sunshine wattle) and Exocarpos cupressiformis (native cherry); on Permian mudstones on well-insolated slopes and crests with northwest to northeast aspects, at elevations between 120 to 250 m above sea level.
What to avoid
- Spread of woody seeds
- Inappropriate burning of habitat
- Damage to individual plants during track and road maintenance
- Off-target damage from herbicides during weed control
- Flower scapes are required to confirm the identity of this ground orchid which dies back to subterranean tubers after flowering. Surveys for Corunastylis nudiscapa should be undertaken during its peak flowering period February to mid April, while noting that fertilised plants can be identified due to the species’ distinctive leaf character in the inflorescence. Leaves have been observed as early as December. The species is difficult to detect due to its diminutive nature, especially where shrubs become denser and usually occurs in low numbers within loose groups at any one site.
- This species is found in open forests and woodlands on mudstone dominated by Eucalyptus tenuiramis (silver peppermint), and occasionally by Eucalyptus obliqua (stringybark) or Eucalyptus amygdalina (black peppermint), with a heathy ground layer of varying density.
Helping the species
- Learn to identify the bare midge-orchid so as to recognise the species if it occurs on your property. If in doubt, seek expert assistance with identification.
- If you live or work in the area where the species occurs (see distribution map, above), look out for and record any observations of the species. All records of this species can provide important information on distribution and abundance.
- If you are interested in knowing for certain whether the species occurs on your land, organise a formal survey. You may need to employ an ecological consultant to do this. Your local Bushcare or Field Naturalist club may be able to assist you with a survey.
- Always report any observations of the species to the Natural Values Atlas, or else provide the data direct to the Threatened Species Section. Records stored on the NVA are a permanent record and are accessible to other people interested in this species.
- Consider the needs of the whole habitat. Preserving a threatened species' habitat is the best way to manage both the species and the environment in which it lives.
- Habitat for the bare midge-orchid corresponds to the following vegetation types in the DPIPWE Bushcare Toolkit: Grassy/heathy woodland and forest, Heathy woodland and forest, and Shrubby forest (all also known as dry sclerophyll). See Eucalypt Bush in the Bushcare Toolkit for more information on managing these vegetation types.
- For long-term protection of populations on private land – consider protection of habitat through a vegetation management agreement or conservation covenant. See the DPIPWE Private Land Conservation Program for more details.
- To protect populations from the establishment and spread of weeds - prevent the spread of weeds in habitat for the bare midge-orchid, and always follow weed management guidelines.
- See the 'What is Needed' section in the bare midge-orchid Listing Statement for a full list of conservation management actions for this species.
Cutting or clearing trees or vegetation
- Localised clearing activities have the potential to inadvertently disturb individual plants and habitat at the extant sites.
- To avoid damage to individual plants and loss of habitat – seek specialist advice when conducting any activities which may involve removal of vegetation in areas where the species is known to occur.
- The importance of fire for bare midge-orchid is not fully understood, although the species does not appear to require fire to stimulate flowering.
- The Bushcare Toolkit provides information on fire management in 'Grassy/heathy woodland and forest', 'Heathy woodland and forest', and 'Shrubby forest' vegetation types.
- To avoid impacts on this species – seek specialist advice when conducting fuel reduction burns in areas where the species is known to occur.
- Localised construction activities for maintaining vehicle tracks for land management purposes (e.g. fire trails) have the potential to inadvertently disturb individual plants and habitat at the extant sites.
- A small amount of ground disturbance appears to be acceptable and perhaps even beneficial, with individual plants remaining near a number of tracks in recent years.
- To avoid damage to individual plants and loss of habitat – seek specialist advice when conducting track-maintenance activities in areas where the species is known to occur.
Changing water flow / quality
Use of chemicals
- To protect individual plants of the bare midge-orchid – avoid off-target herbicide damage to plants during the treatment of weeds within or adjacent to known populations.
- Known populations occur in close proximity to urban areas, and several individual plants occur almost immediately adjacent to open tracks regularly used for recreation, e.g. mountain biking.
- Individual plants can be damaged by trampling by bikes, walkers and dogs.
- To protect known individuals and populations – ensure that the design and maintenance of all recreational and vehicular tracks in the vicinity of known populations takes into account the protection of individual plants at risk from maintenance works and ongoing recreational activities.
Check also for listing statement or notesheet pdf above (below the species image).