Species
Disphyma australe subsp. australe
Etymology
Disphyma: Two-nodule
australe: southern, from the Latin australis
Common Name(s)
horokaka, native ice plant, New Zealand ice plant
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
Disphyma australe (Aiton) N.E.Br. subsp. australe
Family
Aizoaceae
Flora Category
Vascular - Native
Structural Class
Dicotyledonous Herbs other than Composites
Synonyms
Mesembryanthemum australe W.T.Aiton
Distribution
Endemic. New Zealand: Three Kings, North, South, Stewart and Chatham Islands
Habitat
Coastal (rarely inland). Mostly on cliff faces, rock stacks, and boulder/cobble beaches, more rarely in saltmarsh and estuaries. Often in petrel scrub on offshore islands, and extending into coastal forest around petrel burrows. Occasionally on limestone or sandstone cliffs in lowland forest (Western Waikato).
Features
Trailing, succulent herb. Stem terete, glabrous. Short shoots prostrate, rooting freely at nodes. Leaves 3-angled, linear-lanceolate to oblong, acute, often mucronate, tapering to connate base, 6-40 × 4-9 mm; margins entire, smooth, very rarely with a few papillae towards the distal end of the keel. Flowers 20-40 mm diameter. Sepal keel entire, smooth. Petals uniformly white to deep pink, in 3-5 rows, 10-30 mm long. Stamens 4-6 mm long; inner filaments hairy at base. Stigmas (5)-6-8-(10). Capsule valves 5-10, with parallel or ± divergent expanding keels; placental tubercle rounded or 0. Seeds brown, obovoid, rugose, c. 1 mm long.
Similar Taxa
Distinguished from the other New Zealand species by the leaf margin and sepal keel smooth (very rarely papillate near the apex), 3-angled, linear-lanceolate to oblong, acute and often mucronate leaves, and petals in 3-5 rows. The Kermadec endemic subsp. stricticaule differs by the short shoots mostly ascending, rarely rooting at nodes, papillate leaves and sepal keels, and 5 rarely 6 capsule valves.
Flowering
Present throughout the year
Flower Colours
Red / Pink,Violet / Purple
Fruiting
Present throughout the year
Propagation Technique
Easy from rooted pieces and fresh seed. Does well in free draining soil within a sunny site. Not fussy about soil fertility or moisture regime. Some cultivar selection might be necessary as there is a diverse range of foliage colours, and flower colour ranges from white to fully pink.
Threats
Not Threatened
Chromosome No.
2n = 36
Endemic Taxon
Yes
Endemic Genus
No
Endemic Family
No
Life Cycle and Dispersal
Fleshy capsules are dispersed by frugivory and possibly wind and water (Thorsen et al., 2009).
Attribution
Description modified from: Webb, C. J.; Sykes, W. R.; Garnock-Jones, P. J. 1988: Flora of New Zealand. Vol. IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. 4. Christchurch, New Zealand, Botany Division, D.S.I.R. Forms natural intergeneric hybrids with both Carpobrotus chilensis and C. edulis.
References and further reading
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309
This page last updated on 14 Aug 2014