Magnificent Helicarionid Land Snail (Gudeoconcha sophiae magnifica)
This land snail subspecies is endemic to Lord Howe Island, NSW, where it occurs on the summits and upper slopes of the southern mountains. It is associated with leaf litter in mountain habitat, including cloud rainforest on Mt Gower.
Conservation status
Commonwealth, EPBC Act 1999: Critically endangered.
New South Wales, Biodiversity Conservation Act 2016: Critically endangered.
Seasonal planning
No species-specific activity or breeding months were found in the published sources used. Use the following as a works-planning prompt, not as seasonal biology.
Seasonal knowledge: Not documented in the sources used.
The month values are a general planning prompt only and do not represent known activity or breeding months for Gudeoconcha sophiae magnifica.
- Plan checks before disturbance: General planning window only. Check the work area before disturbance whenever works are scheduled.
Identification: Appearance
It has a thin bronze shell with a depressed spire and fine ripple-like markings. The shell is about 35 mm in diameter and 20 mm high.
It has a thin bronze shell with a depressed spire and fine ripple-like markings. The shell is about 35 mm in diameter and 20 mm high.
Identification: Confirming identity
Confirm the identity of any suspected record with a specialist and a photograph or voucher, as required by the relevant permit.
Distribution: Known range
The snail is known from the peaks of Mt Gower and Mt Lidgbird on Lord Howe Island. Its occupied area is thought to be less than 28 hectares, and it has also been recorded on the upper slopes and summit of Mt Gower.
The snail is known from the peaks of Mt Gower and Mt Lidgbird on Lord Howe Island. Its occupied area is thought to be less than 28 hectares, and it has also been recorded on the upper slopes and summit of Mt Gower.
Distribution: National mapping
The Commonwealth species distribution model (SNES) maps where the species or its habitat is known, likely or may occur. Use it with local records and site inspection.
Habitat: Habitat
It occurs in leaf litter on the summits and upper slopes of the island’s southern mountains, including cloud rainforest on Mt Gower. Southern-mountain land snails are ground-dwellers and can be found among ground cover.
It occurs in leaf litter on the summits and upper slopes of the island’s southern mountains, including cloud rainforest on Mt Gower. Southern-mountain land snails are ground-dwellers and can be found among ground cover.
Foraging habitat: Diet
Not documented in the published sources used for this profile.
Not documented in the published sources used for this profile.
Breeding habitat: Breeding
Not documented in the published sources used for this profile.
Not documented in the published sources used for this profile.
Sheltering habitat: Shelter
It is a ground-dwelling snail that can be found under leaves, palm fronds, rocks and logs.
It is a ground-dwelling snail that can be found under leaves, palm fronds, rocks and logs.
Threats: Threats
The snail is susceptible to human disturbance, weeds and bushfires. Feral pigs and goats disrupted its fragile habitat before their eradication.
The snail is susceptible to human disturbance, weeds and bushfires. Feral pigs and goats disrupted its fragile habitat before their eradication.
Threats: Works risk
Works that disturb habitat in its restricted mountain range could affect the snail, which is susceptible to human disturbance. Weeds and bushfires are also identified as risks to its fragile habitat.
Survey methodology: 1. Species-specific methods
Use methods consistent with the Commonwealth survey guidelines and engage a specialist with the right permits.
Targeted systematic surveys have been undertaken on Mt Gower and on the upper to mid-slopes of Mt Gower and Mt Lidgbird. Patient searching under leaves, palm fronds, rocks and logs is described for ground-dwelling land snails.
Survey methodology: 2. Commonwealth guidance
For EPBC Act referrals, survey effort and methods should be consistent with the on-ground surveys and data for referred actions under the EPBC Act, read with the Significant impact guidelines 1.1.
Survey methodology: 3. Limits
A non-detection is not proof of absence. Match survey timing to the species and season, and record effort.
Vegetation associations: Rainforest or vine thicket
Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.
It occurs in leaf litter on the summits and upper slopes of the island’s southern mountains, including cloud rainforest on Mt Gower.
Automatically indexed from existing profile text. Not a verified preference, mapped occurrence or habitat requirement. Check the original source and regional qualifiers before use.
Evidence: Unreviewed profile-derived candidate
Confidence: Not independently verified
Region: Scope as described in the quoted profile text; not independently verified. Profile states: NSW.
Habitat use: general
Ecosystem associations
Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.
No species-specific ecosystem association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.
Soil and substrate associations
Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.
No species-specific soil association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.
Water and wetland associations
Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.
No species-specific water association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.
Fauna records and mapped habitat: Not yet analysed
Record locations can be overlaid with mapping, but record frequency alone does not measure habitat preference. No species is excluded from desktop assessments by this analysis.
No quality-controlled record-to-map analysis has been completed for this species. The existing generalised distribution dots and indicative range polygons have not been treated as precise occurrence coordinates.
A defensible run needs dated, independently attributable records, coordinate uncertainty, duplicate and captive-record checks, layer versions and regional scope. Preference and absence require additional survey-effort and detection evidence.
Habitat limitations and contrary evidence: No supported exclusion recorded
Not recorded is not the same as cannot occur. Low suitability, resident habitat, breeding habitat and occasional movement are different conclusions.
This library has not established a vegetation, ecosystem or soil-type exclusion for this species. This does not mean all habitat is suitable; the evidence needed to justify an exclusion has not been assembled.
Habitat limitations and contrary evidence: Before using a negative association
- Confirm the taxon, geographic region, life stage and habitat function covered by the evidence.
- Check survey methods, season, repeated effort and detectability before interpreting non-detection.
- Investigate credible contradictory records and microhabitats absent from broad mapping.
- Do not convert a missing map class, low record count or failed data request into species absence.
Before disturbance: 1. Desktop and approvals
Confirm whether the project could affect the species before works begin.
Check national mapping, state records and recent surveys for the site. An action likely to have a significant impact on this nationally listed species needs EPBC Act referral, and state permits apply where it is state listed.
Before disturbance: 2. Plan to avoid
Design the footprint, timing and access to avoid known or likely habitat, and brief crews on what to look for and who to call.
During disturbance: 1. Controls
Keep works inside the approved footprint and conditions.
Fence or mark habitat to be retained and keep machinery, stockpiles and spoil out of it.
During disturbance: 2. Stop and report
If the species is found unexpectedly, stop work at that spot and contact the project ecologist and the relevant agency.
After disturbance: 1. Records
Record outcomes.
Record sightings, habitat lost or retained and any injury or death, and report them under the approval conditions.
Rehabilitation: 1. Restore
Restore disturbed habitat where possible.
Reinstate disturbed ground with local species, return logs, rocks and litter, and control weeds and erosion until the site is stable.
Sources
- EPBC Act species profile (SPRAT): Gudeoconcha sophiae magnifica, Department of Climate Change, Energy, the Environment and Water: https://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=82864
- Species of National Environmental Significance, public grids (August 2026 extract), Department of Climate Change, Energy, the Environment and Water: https://fed.dcceew.gov.au/datasets/9d313bb078b9421ebebc835b3a69c470/about
- Biodiversity Conservation Act 2016 (NSW), threatened species schedules, NSW Government: https://legislation.nsw.gov.au/view/whole/html/inforce/current/act-2016-063
- Gudeoconcha - Wikipedia, en.wikipedia.org: https://en.wikipedia.org/wiki/Gudeoconcha
- Magnificent discoveries on Lord Howe Island - Australian Museum, australian.museum: https://australian.museum/blog/amri-news/magnificent-discoveries-on-lord-howe-island/
- Invertebrates | Lord Howe Island Rodent Eradication Project, lhirodenteradicationproject.org: https://lhirodenteradicationproject.org/plants-animals/invertebrates/
- Magnificent helicarionid land snail, australiangeographic.com.au: https://www.australiangeographic.com.au/nature-wildlife/2014/02/magnificent-helicarionid-land-snail/
- Everything you ever wanted to know about snails (on Lord Howe Island), australiangeographic.com.au: https://www.australiangeographic.com.au/news/2020/09/everything-you-ever-wanted-to-know-about-snails-on-lord-howe-island/
- [PDF] Saving our Species project 2019-20 annual report card Magnificent ..., nswdpe.intersearch.com.au: https://nswdpe.intersearch.com.au/nswdpejspui/bitstream/1/22066/1/magnificent-helicarionid-land-snail-gudeoconcha-sophiae-magnifica-2019-20.PDF
- On-ground surveys and data for referred actions under the EPBC Act, Department of Climate Change, Energy, the Environment and Water: https://www.dcceew.gov.au/environment/epbc/advice/surveys-and-data
- Atlas of Living Australia: scatterplot case study and survey-effort limitations, Habitat evidence reference: https://support.ala.org.au/support/solutions/articles/6000208426-scatterplot-case-study