The New Zealand Plant Conservation Network

Species

Asplenium obtusatum

Etymology

Asplenium: From the Greek a- 'without' and splene 'spleen', a northern hemisphere species, the black spleenwort (Asplenium adiantum-nigrum), was once believed to be a cure for diseases of the spleen.
obtusatum: Obtuse, or blunt

Common Name(s)

shore spleenwort

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

Asplenium obtusatum G.Forst.

Family

Aspleniaceae

Flora Category

Vascular - Native

NVS Species Code

ASPOBT

Structural Class

Ferns

Synonyms

Asplenium obtusatum var. obliquum (G.Forst.) Hook.f.; Asplenium apice-dentatum Homb. et Jacq.; Asplenium lucidum var. obliquum (G.Forst.) Moore; Asplenium obtusatum G.Forst. subsp. obtusatum

Distribution

Indigenous. New Zealand: North (Cook Strait only), South, Chatham, Stewart, Snares, Antipodes, Auckland and Campbell Islands. Also South America as well as on many islands of the southern Atlantic and Pacific Oceans.

Habitat

A coastal fern confined in the northern part of its range to only the most exposed situations. Further south it grows not only on exposed cliffs but also in coastal vegetation where it often forms an important association with Hebe elliptica and Blechnum durum. Frequently associated with sea bird colonies.

Features

Rhizome stout, often forming a hard woody mass above ground, bearing brown, shiny, ovate, acuminate scales up to 15 x 4 mm. Stipes 40-300 mm long, dark brown at base, green above, stout, covered in ovate scales with acute or acuminate apices. Laminae ovate, 60-400 ~ 50-200 mm, dull green, very thick and fleshy, pinnate. Raches green, stout, prominently grooved and scaly. Pinnae 5-15 pairs, 20-narrowly ovate to oblong, obtuse to acute, crenate-serrate to entire, cuneate at base, 100 ~ 10-25 mm, scaly on the underside. Sori up to 10 mm long, not reaching to lamina edge.

Similar Taxa

Recognized by the penchant for exposed sea cliffs; by the simply pinnate, thick and fleshy fronds which are < 30 mm wide; by the stipe and rachis which is scaly; by the usually < 8 pairs of pinnae; and by the pinnae bearing scales on the underside only. Asplenium decurrens differs from A. obtusatum by its allopatric distribution, narrowly triangular scales, mostly smaller fronds, larger spores and octoploid chromosome number (2n = 288 cf. 2n = 144 in A. obtusatum)

Flowering

Not applicable - spore producing

Flower Colours

No Flowers

Fruiting

Not applicable - spore producing

Propagation Technique

Easily grown but generally rather slow. A spectacular pot plant. Thrives with added poultry manure, thus simulating its common habitat of coastal seabird colonies (Ogle 1987).

Threats

Not Threatened

Chromosome No.

2n = 144

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

This page last updated on 2 Mar 2017