The New Zealand Plant Conservation Network

Species

Polystichum neozelandicum subsp. neozelandicum

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 neozelandicum Fée subsp. neozelandicum

Family

Dryopteridaceae

Flora Category

Vascular - Native

Structural Class

Ferns

Synonyms

Polystichum neozelandicum Fée, Polystichum richardii (Hook.) J.Sm.

Distribution

Endemic. New Zealand: Three Kings, North and 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.

Features

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 third 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 in the former (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.

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 neozelandicum (either subspecies) is also an excellent pot plant.

Threats

Not Threatened

Chromosome No.

2n = c.328

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 7 Jan 2014