Polystichum oculatum
Synonyms
Aspidium oculatum Hook.
Family
Dryopteridaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Ferns
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.
POLOCU
Chromosome number
2n = c.164
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened
Previous conservation statuses
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Habitat
Coastal and lowland forest and scrub margins, usually on hillsides and on colluvium and alluvium soils under scrub. It has also extended its range into urban situations where it sometimes a feature of roadside banks and cuttings.
Detailed description
Rhizomes short, erect. Stipes 90–300 mm long. Stipes andrachises moderately to only sparsely scaly. Scales large; often pentagonal, such that they are widest near mid length; those from the stipe-rachis junction 770–2280 µm (usually > c. 1000 µm) wide at mid length; pale brown to dark brown, sometimes bicolorous but never with a dark centre completely enclosed by a pale margin; apex often appearing quite blunt because of dehiscence of apical cell(s); almost always with marginal projections which often taper to cilia-like apices; underlain by smaller scales, including ‘arachnioid’ scales with fimbriate bases, but these only sparse, such that stipe and rachis never appear completely clothed in indumentum. Lamina 180–410 × 80–200 mm, bipinnate (with the lower primary pinnae of some large fronds being tripinnate); usually blue-green and almost concolorous with blackish blue primary and secondary costae. Primary pinnae in 11–22 pairs, the longest 43–105 × 16–43 mm. Secondary pinnae stalked and free towards the base of primary pinnae, becoming sessile and adnate towards the apex of primary pinnae; never entire, 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 (5–50% of surface area).
Similar taxa
Polystichum oculatum is recognised by its broad, often pentagonal scales, widely inserted and relatively broad pinnae, indusia with obvious dark centres, and relatively small spores. However it is superficially similar to P. neozelandicum subsp. zerophyllum, with which it often grows. Polystichum neozelandicum subsp. zerophyllum differ by its narrower scales and larger spores. The often stark contrast in colour between the primary costae (blackish blue) and the remaining lamina (forest green) in P. neozelandicum subsp. zerophyllum compared with the more uniform colouring (blackish blue to dark blue-green) in P. oculatum can be a useful initial field character. Hybrids may further complicate identification, although these can be recognised by their aborted spores.
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 oculatum is also an excellent pot plant.
Etymology
polystichum: Many rows (of sori); from the Greek polus and stikhos; parallel rows of spore cases
Where To Buy
Not Commercially Available.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (13 November 2012). Description adapted from Perrie et al. (2003).
References and further reading
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.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Polystichum oculatum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/polystichum-oculatum/ (Date website was queried)