Adiantum cunninghamii
Common names
common maidenhair, Cunningham’s maidenhair
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Ferns
Detailed description
Tufted, terrestrial fern. Rhizomes, short- to long-creeping. Stipes and rachises glabrous. Fronds adaxially dark green or glaucescent, abaxially paler, glaucous green, ovate to elliptic. Lamina 100–350 × 50–240 mm, 2–3-pinnate at base. Ultimate segments stalked to one side, oblong, tending to curve acroscopically at apices, upper margins irregularly toothed, lower margins smooth, glabrous. Indusia kidney-shaped, glabrous.
Similar taxa
Could be confused with Adiantum fulvum, and A. viridescens. From both it is immediately distinguished by the glabrous rather than hairy primary pinnae. However, in situations of uncertainty A. fulvum is easily distinguished by its glabrous rather than hairy ultimate segment undersides, and A. viridescens differs by the narrower often sickle-shaped, shiny, dark green, ultimate segments, and glabrous primary pinnae.
Distribution
Endemic. New Zealand: Kermadec Islands, Manawatāwhi / Three Kings Islands, North Island, South Island, Stewart Island/Rakiura, Chatham Islands.
Habitat
Common throughout in coastal and lowland forest, occasionally extending into upper montane forests. Usually found on banks, cliff faces and amongst boulders—especially on limestone, marble, basalt or andesite rocks.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened
Detailed taxonomy
Genus
Family
Synonyms
Adiantum formosum var. cunninghamii (Hook.) F.Muell.; Adiantum trapeziforme G.Forst.; Adiantum affine var. chathamicum Field; Adiantum affine var. pullum (Colenso) Domin; Adiantum affine sensu G.M. Thomson; Adiantum formosum sensu A.Rich.; Adiantum pullum Colenso
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Life cycle and dispersal
Minute spores are wind dispersed (Thorsen et al., 2009).
Propagation technique
Slow but once established easy. Best grown from spores which must be sown fresh. Spores may take several years to produce plants.
Other information
Etymology
adiantum: From the Greek a- ‘without, lacking’ and diantos ‘moistened’, the fronds of this fern are supposed to remain dry after submersion in water
cunninghamii: Named after Allan Cunningham (1791–1839) who was an English botanist and explorer, primarily known for his travels to Australia (New South Wales) and New Zealand to collect plants. Author of Florae Insularum Novae Zelandiae Precursor, 1837–40 (Introduction to the flora of New Zealand).
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
ADICUN
Chromosome number
2n = 116
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Auckland: 2025 | Regionally Not Threatened | Qualifiers: DPS, DPT
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Auckland conservation status information is sourced from the “Conservation status of vascular plant species in Tāmaki Makaurau / Auckland” Simpkins E et al. (2025) report.
Otago: 2025 | Regionally Not Threatened
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Conservation Status of Indigenous Vascular Plants in Otago, 2025” Jarvie S et al. (2025) report.
Referencing and citations
References and further reading
Brownsey PJ, Smith-Dodsworth JC. 2000. New Zealand Ferns and Allied Plants. David Bateman, Auckland, NZ. 168 p.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309. https://doi.org/10.1016/j.ppees.2009.06.001.
Attribution
Fact Sheet Prepared for NZPCN by: P.J. de Lange (June 2005). Description adapted from Brownsey & Smith-Dodsworth (2000).