Polystichum neozelandicum subsp. neozelandicum
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Ferns
Detailed description
Rhizomes short, erect. Stipes 100–420 mm long. Stipes and rachises moderately to densely scaly. Scales obviously scale-like to the naked-eye; usually acicular-lanceolate; usually widest in the basal ⅓ of length; those from the stipe-rachis junction usually 135–570 µm wide at mid length; mid to dark brown, often appearing black to the naked eye; apex tapering; margins almost always with projections which usually taper to cilia-like apices; underlain by smaller scales, including ‘arachnioid’ scales with fimbriate bases. Lamina 175–525 × 90–220 mm, bipinnate with the basal primary pinnae of some large fronds becoming tripinnate; usually forest green with primary and secondary costae blackish blue. Primary pinnae in 11–25 pairs, the longest 45–120 × 5–38 mm. Secondary pinnae stalked and free towards the base of primary pinnae, becoming sessile and adnate towards the apex of primary pinnae; with sharply pointed apices and usually additional marginal teeth and/or crenulations. Sori round. Indusia peltate, ± flat, ± round, with entire, although often undulate and/or scalloped, margins; persistent; central dark area always significant and obvious (15–60% surface area, and usually > c. 30%).
Similar taxa
According to Perrie (2003) the distributions of P. neozelandicum subsp. neozelandicum and subsp. zerophyllum do not overlap. Both subspecies are primarily distinguished by the size of the dark pigmented centre of the indusia, which in subsp. neozelandicum is usually larger (Perrie 2003) viz, 15–60% surface area, and usually > c. 30% in subsp. neozelandicum and 5-30% surface area in subsp. zerophyllum. However, on the Chatham Islands at least, both subspecies are sympatric (de Lange et al. 2011). Some botanists have reported that the distinctions between the two subspecies overlaps and that it may be better to regard P. neozelandicum as just the one species (C. Ecroyd pers. comm.). Polystichum oculatum is superficially similar. It is distinguished by its broad, often pentagonal scales, widely inserted and relatively broad pinnae, indusia with obvious dark centres, and relatively small spores. Polystichum wawranum is also somewhat similar. However it is distinguished by its hair-like scales, closely inserted and relatively long narrow pinnae, indusia mostly lacking obvious dark centres, and relatively small spores. Polystichum wawranum is often sympatric with both subspecies of P. neozelandicum.
Distribution
Endemic. New Zealand: Manawatāwhi / Three Kings Islands, North Island, Chatham Islands. Common from Te Paki south to Awakino and Bay of Plenty (exact southern limits not clear). On the Chatham Islands it is scarce.
Habitat
Coastal to lowland (extending rarely into lower montane habitats). Common fern of forested hillsides and banks, coastal cliff faces (under scrub), usually in well-lit conditions. It has also extended its range into urban situations where it sometimes a feature of roadside banks and cuttings.
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
Family
Synonyms
Polystichum neozelandicum Fée, Polystichum richardii (Hook.) J.Sm.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Propagation technique
Easily grown from fresh spores and transplants. However, often slow to establish. Does best in a shaded site planted within a deep, free draining humus-enriched fertile soil. Polystichum neozelandicum (either subspecies) is also an excellent pot plant.
Other information
Cultivation
Sometimes commercially available, and then often sold as Polystichum richardii.
Etymology
polystichum: Many rows (of sori); from the Greek polus and stikhos; parallel rows of spore cases
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.
POLNSN
Chromosome number
2n = c.328
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
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 “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | Regionally Not Threatened
Referencing and citations
References and further reading
de Lange PJ, Heenan PB, Rolfe JR. 2011. Checklist of vascular plants recorded from Chatham Islands. Department of Conservation, Wellington, NZ. 57 p. https://www.doc.govt.nz/globalassets/documents/conservation/native-plants/chatham-islands-vascular-plants-checklist.pdf
Perrie LR, Brownsey PJ, Lockhart PJ, Large MF. 2003. Evidence for an allopolyploid complex in New Zealand Polystichum (Dryopteridaceae). New Zealand Journal of Botany 41(2): 189–215. https://doi.org/10.1080/0028825X.2003.9512841.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (13 November 2012). Description adapted from Perrie et al. (2003).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Polystichum neozelandicum subsp. neozelandicum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/polystichum-neozelandicum-subsp-neozelandicum/ (Date website was queried)