The New Zealand Plant Conservation Network

Species

Carex kermadecensis

Etymology

Carex: Latin name for a species of sedge, now applied to the whole group.
kermadecensis: From the Kermadec Islands

Common Name(s)

Kermadec Sedge

Current Conservation Status

2012 - At Risk - Naturally Uncommon

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 - At Risk - Naturally Uncommon
2004 - Range Restricted

Qualifiers

2012 - CD, IE
2009 - IE

Authority

Carex kermadecensis Petrie

Family

Cyperaceae

Flora Category

Vascular - Native

NVS Species Code

CARKER

Structural Class

Sedges

Synonyms

Carex forsteri Wahl. subsp. insularis W.R.B.Oliver

Distribution

Endemic. Kermadec Islands group where it is known only from Raoul and Macauley Islands.

Habitat

Coastal forest where it is usually found amongst boulders, rubble and near sea bird nesting sites. Sometimes found in open exposed places but generally prefers shaded situations.

Features

Rather robust tufted, light yellow-green to green tussock forming sedge usually of shaded forested slopes. Culms up to 450 mm tall, 2 mm diameter, triquetrous, finely and faintly scabrid just below inflorescence; basal sheaths light brown. Leaves much > culms, 7-10 mm wide, double-folded, margins scabrid. Inflorescence of 5-10 usually compound spikes. Spikes 20-55 x 5-7 mm, approximate or with the lower 2-4 more distant, erect on stiff peduncles; the terminal spike wholly or mostly male, or completely female; remaining spikes female with occasional male flowers at the base; lower subtending bracts leaf-like, much > inflorescence. Glumes (excluding awn) < utricles, ovate-oblong, emarginated or acute, margins fimbriate towards apex, light brown or with minute dark brown flecks, chartaceous to membranous, awns up to 3 mm long, pale green to straw-coloured, scabrid,. Utricles 3-4 x 1.5 mm, trigonous, ellipsoid or more or less ovoid, nerves distinct, membranous, grey-brown with red-brown flecks, beck 1-2 mm long, deeply and acutely bifid, orifice and margins of beak and of upper part of utricles usually scabrid. Stigmas 3. Nut 2 mm long, dark brown, trigonous, oblong-obovoid.

Similar Taxa

As the only carex on the Kermadecs field identification is not usually a problem. However, herbarium material could be confused with C. elingamita Hamlin of the Three Kings Islands group. From that species C. kermadecensis differs consistently by the lowermost spikes predominantly female rather than largely male toward the top, by the utricles 3-4 rather than 4-4.5 mm long and by the nut coloured dark brown rather than red brown. That they are closely allied is inferred from nrDNA ITS sequences which position both species as sister taxa.

Flowering

October - January

Fruiting

October - May

Propagation Technique

Easily grown in a warm sheltered site, prefers semi-shade. Very cold sensitive.

Threats

A naturally uncommon , range restricted species. However, it has not been seen on Macauley Island since 1989.

Chromosome No.

2n = c.60

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).

This page last updated on 30 May 2014