Isolepis habra
Biostatus
Native
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened | Qualifiers: SO
Category
Vascular
Structural class
Sedges
Detailed description
Slender perennial, in close-packed tufts from a shortly creeping rhizome. Culms 50–300 mm long, less than 0.5 mm in diameter, soft and usually flaccid; basal bracts light reddish brown. Leaves 1–3–(4) per culm, bright green, soft, usually flaccid, shorter than the culms; sheaths often tinged with red-purple. Inflorescence of 1–3 ovate spikelets, occasionally proliferous, subtending bract up to 6 times the length of spikelet. Spikelets 2–4–5 × 2–3 mm, varying in colour from pale green, through green tinged with red-purple to almost entirely black. Glumes (1.0)–1.2–1.8 mm long, ovate-elliptical, acute, keel green, prominent, often slightly excurrent, sides wholly cream, or with red-purple markings to almost entirely dark red-purple, but then often with pale cream nerves. Stamens 1–2–(3), usually distributed as 2 in lower glumes, usually only 1 stamen in upper glumes. Style branches 3. Hypogynous bristles 0. Nut 1.0–1.4 × 0.6–0.8 mm, obovate-elliptical, trigonous with angles slightly thickened, cream to sometimes light brown, minutely stipitate and apiculate.
Similar taxa
Recognised by the usually flaccid growth habit, culms which are usually < 0.5 mm diameter and > 60 mm long, stamens mostly 2 per lovwer glumes and 1 per upper, and by ribbed nut < 1 mm long. Spikelet colour varies in the northern two-thirds of New Zealand these are uniformly light green or reddish black but in the southern South Island, Stewart Island/Rakiura and Chatham Islands especially they are mostly dark black with cream nervation.
Distribution
Indigenous. New Zealand: North Island, South Island, Stewart Island/Rakiura and Chatham Islands. Also Australia.
Habitat
In the northern part of its range strictly montane, usually in cloud forest on permanantly damp peaty ground. Extending to sea level in southern part of range , where it may grow in open coastal turf, peat bogs and in damp sites under coastal scrub and forest.
Detailed taxonomy
Genus
Family
Synonyms
Scirpus habrus Edgar; Isolepis limbata W.M.Curtis,
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
Throughout the year but peaking in October–December
Fruiting
Throughout the year
Life cycle and dispersal
Nuts are dispersed by water and possibly granivory and attachment (Thorsen et al., 2009).
Propagation technique
Easily grown from rooted pieces, by seed or from the division of established plants. An attractive plant for a shady, damp site or planted in shallow water around a pond. The Chatham Islands form whcih has darker black spikelets is especially attractive.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Other information
Where To Buy
Not commercially available.
Etymology
isolepis: From the Greek isos (equal) and lepis (scale)
habra: Soft, delicate
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.
ISOHAB
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened | Qualifiers: SO
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Otago: 2025 | Regionally Not Threatened
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Conservation Status of Indigenous Vascular Plants in Otago, 2025” Jarvie S et al. (2025) report.
Referencing and citations
References and further reading
Johnson AT, Smith HA. 1986. Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd, Buckenhill, UK.
Moore LB, Edgar E. 1970. Flora of New Zealand, Volume II. Indigenous Tracheophyta: Monocotyledones except Gramineae. Government Printer, Wellington, NZ. 354 p.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309.
Attribution
Description adapted from Moore and Edgar (1970)
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.