clings to the damp rocky cliff faces
- Size
- Length: 15-20 cm
- Lifespan
- Unknown
- Diet
- Photosynthetic. Obtains nutrients via rainwater and rock weathering in crevices.
- Habitat
- Rocky crevices and cliff faces in coastal and montane areas. Prefers shaded damp sites with minimal soil.
- Range
- Throughout North and South Islands. Most common on rocky outcrops and cliff faces in coastal and montane areas.
- Endemism
- Native
- Main Threats
- Habitat loss from quarrying and construction. Climate change affecting moisture levels. Rock face modification disrupts growth.
- Population
- Not Threatened status. Widespread throughout North and South Islands. Population stable in suitable rocky habitat.
- Conservation Status
- Not Threatened
- Human Risk
- harmless
- Handling Note
- native fern; leave undisturbed in habitat
- Te Ao Māori
- Ring fern has no recognised Māori name, being a small inconspicuous fern likely grouped with other rock-dwelling species by early Māori communities. Its restricted habitat on cliff faces meant it was probably less significant than larger edible ferns. Today the species serves as an indicator of geological stability. Its presence signals intact rock formations and suitable moisture levels. Conservation efforts focus on protecting remaining rocky outcrops from development and quarrying activities.
Photosynthesis drives it. Not consumption. The ring fern obtains energy from sunlight and nutrients from rainwater and rock weathering. This lithophytic adaptation allows it to thrive in nutrient-poor environments where other plants struggle. It reaches about 20 centimetres in height with narrow fronds that grow in tight rings around rock crevices.
The species inhabits shaded damp crevices in coastal and montane areas. It prefers minimal soil, anchoring itself with shallow roots in cracks and fissures. Unlike forest ferns that require deep leaf litter, this spleenwort thrives on bare rock where competition is low. Spores are produced on the underside of fertile fronds in linear sori along the veins. These spores are released into the air, drifting on wind currents until they land on suitable rocky substrate.
Classified as Not Threatened, ring fern remains widespread throughout New Zealand. Populations are stable in suitable rocky habitat. However the species is sensitive to habitat disturbance. When rock faces are modified for construction or quarrying, populations decline rapidly. Its presence signals intact geological features and suitable moisture levels. Conservation efforts focus on protecting remaining rocky outcrops from development and maintaining natural hydrological regimes.