Austroblechnum norfolkianum

Common Name(s)

None Known

Current Conservation Status

2012 - At Risk - Naturally Uncommon

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - At Risk - Naturally Uncommon
2004 - Sparse


2012 - TO
2009 - TO


Austroblechnum norfolkianum (Heward) Gasper et V.A.O.Dittrich



Flora Category

Vascular - Native

NVS Species 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.

Structural Class



Lomaria norfolkiana Heward, Blechnum lanceolatum var. norfolkianum (Heward) Laing, Blechnum norfolkianum (Heward) Maiden nom. superf., nom. illeg., Lomaria acuminata Baker nom. illeg. non Desv. (1811), nec C.Presl. (1825), Spicanta acuminata (Baker) Kuntze, nom. illeg., Blechnum acuminatum (Baker) Maiden nom. illeg. non Fée (1852), nec Sturm (1853); Lomaria attenuata sensu Hook.f.; Blechnum norfolkianum (Heward) C.Chr.


Indigenous. Common on Raoul Island (Kermadec Island group) and the Three Kings Islands, otherwise uncommon and sparingly distributed on mainly offshore islands from the Cavallis south to Mayor Island. Known on the Chatham Islands from South East (Rangatira) Island. Also on Norfolk Island where it is now seriously at risk of extinction


Strictly Coastal. This species is most frequently seen on the outer Hauraki Gulf offshore islands, and on the more remote Three Kings and Kermadecs. It favours shaded sites, usually in or near petrel colonies, or near penguin trails and nests.


Tufted fern. Rhizomes stout, erect. Covered in old stipe ends. Stipes of sterile fronds 50-150 mm long, scaly at base. Sterile laminae narrowly elliptic, pinnate, 350-900 x 90-180 mm, dark green to bright green, never red-tinged. somewhat fleshy, upper surfaces shining, glabrous. Sterile pinnae in 35-60 pairs, longest at the middle, 50-90 x 8-18 mm, falcate and tapering to acute apices, gradually reducing to short flanges at base, margins finely toothed, bases adnate. Fertile fronds only slightly shorter than sterile.

Similar Taxa

Most often confused with Austroblechnum lanceolatum, from which it is most reliably distinguished by its dark green to bright green, somewhat fleshy fronds, which are never red or pink-tinged, by the distinctly sickle-shaped (falcate) pinnules and much shorter fertile fronds (these are usually half the length of the sterile fronds). In New Zealand A. norfolkianum is an offshore island species, usually found in or near petrel burrows in deeply shaded forest or in rocky sites within overhands and damp recesses


Not applicable - spore producing

Flower Colours

No Flowers


Not applicable - spore producing

Propagation Technique

Easy from fresh spores. Does best in a sheltered spot planted within free draining, fertile, moist soil. Responds well to frequent mulching with partially rotted leaf litter.


Not threatened in New Zealand, although close to extinction on Norfolk Island. In New Zealand it has a primarily northern offshore island distribution, and is by and large uncommon except on the Kermadec and Three Kings Islands.

Chromosome No.

2n = c.66

Endemic Taxon


Endemic Genus


Endemic Family



Perrie et al. (2014) advocated for a broadened circumscription of Blechnaceae whereby a number of genera traditionally recognized as distinct from Blechnum were merged within it. However, this view has not met with universal acceptance (see Gasper et al. 2016) and does not seem to be followed worldwide (PPG 2016). From a New Zealand perspective the decision to merge Doodia in Blechnum, and rejection of Diploblechnum has not been universally accepted either e.g., Wilcox & Warden (2017), and as such it is considered appropriate to follow world opinion and accept the taxonomy of Gasper et al. (2016) and recommendations of the PPG (2016). See also the comments by Pyner (2017).

Fact Sheet Citation

Please cite as:  de Lange, P.J. (Year at time of Access): Austroblechnum norfolkianum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. http://www.nzpcn.org.nz/flora_details.aspx?ID=225 (Date website was queried)


Fact Sheet by P.J. de Lange 6 June 2005. Description from Brownsey & Smith-Dodsworth (2000).

References and further reading

Brownsey, P.J.; Smith-Dodsworth, J.C. 2000: New Zealand ferns and allied plants. David Bateman Ltd, Auckland

Gasper, A.L.; de Oliveira Dittrich, V.A.; Smith A.R.; Salino, A. 2016:  A classification for Blechnaceae (Polypodiales: Polypodiopsida): New genera, resurrected names, and combinations. Phytotaxa 275: 191–227.

Perrie, L.R.; Wilson, R.K.; Shepherd, L.D.; Ohlsen, D.J.; Batty, E.L.; Brownsey, P.J.; Bayly, M.J. 2014: Molecular phylogenetics and generic taxonomy of Blechnaceae ferns. Taxon 63(4): 745-758.

PPG 1: The Pteridophyte Phylogeny Group 2016: A community-derived classification for extant lycophytes and ferns. Journal of Systematics and Evolution 54: 563-603.

Pyner, T. 2017: A new classification of Blechnum. British Pteridological Society. https://ebps.org.uk/new-classification-blechnum/

Wilcox, M.; Warden, J. 2017: Botany of Hillsborough coast bush reserves, Manukau Harbour, Auckland. Auckland Botanical Society Journal 72: 32-46.



This page last updated on 5 Sep 2017