The New Zealand Plant Conservation Network

Species

Polystichum oculatum

Etymology

Polystichum: Many rows (of sori); from the Greek polus and stikhos; parallel rows of spore cases

Current Conservation Status

2012 - Not Threatened

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 - Not Threatened
2004 - Not Threatened

Authority

Polystichum oculatum (Hook.) J.B.Armstr.

Family

Dryopteridaceae

Flora Category

Vascular - Native

NVS Species Code

POLOCU

Structural Class

Ferns

Synonyms

Aspidium oculatum Hook.

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.

Features

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.

Flowering

Not Applicable - Spore Producing

Flower Colours

No Flowers

Fruiting

Not Applicable - Spore Producing

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.

Threats

Not Threatened

Chromosome No.

2n = c.164

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 7 Jan 2014