Tillaea hamiltonii Kirk nom. nud.
Vascular – Native
Dicotyledonous Herbs other than Composites
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.
2n = 72
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2018 | Threatened – Nationally Vulnerable
Previous conservation statuses
2012 | Data Deficient | Qualifiers: Sp
2009 | At Risk – Declining | Qualifiers: DP, Sp
2004 | Serious Decline
Endemic to New Zealand. In the North Island only known from the N.W. Ruahine corner. In the South Island localised but widespread, with its main centre of distribution Otago, western Southland, Fiordland and Stewart Island.
A species of open, compact turf communities such as those developed along lake and tarn margins, flushes and seepages. Occasionally found in suitably open sites within forest.
Creeping perennial herb rooting at nodes forming diffuse to dense turf-like patches. Stems fleshy, distinctly angled, square in cross-section, dark striped. Leaves opposite, 2 x 2 mm, broadly ovate to obovate-oblong, bright green or mottled with red, fleshy, sparsely covered with indistinct circular oil glands, glabrescent (leaf margins often faintly ciliolate), shortly petiolate to sessile, bases decurrent with stem. Flowers soliatry, off-white to greenish-white. Calyx-lobes minute, ovate-triangular, corolla lobes 4, obovate-oblong, pubescent. Stamens and styles 4. Fruit of 4 brown setulose nutlets. These broadly elliptic or obovate, (1-)1.1-1.4(-1.5) mm.
Without fruits this diminutive creeping herb could be easily confused with a diverse range of other unrelated turf-forming herbs, e.g., Nertera spp., Crassula spp., Galium spp. However, the distinctive 4-fruited setulose nutlets immediately distinguish it from these and other potential look alikes.
Flowers may be found throughout the year
Fruits may be found throughout the year
Easily grown from the division of whole plants.
A naturally uncommon species of open damp turf, seepages, and the marginal turf communities of lakes and tarns. Sometimes in open scrub or damp grassland. Indications are that in parts of its range it is declining possibly as a consequence of taller, faster growing weeds spreading into the habitats it requires.
hamiltonii: Named after W. S. Hamilton (of Southland)
Where To Buy
Not commercially available but plants are held by several Botanic Gardens and specialist growers. It is very easily grown but is not particularly attractive.
Fact Sheet prepared for NZPCN by P.J. de Lange 1 August 2003. Description based on Allan (1961).
References and further reading
Allan, H.H. 1961: Flora of New Zealand. Vol. I. Wellington, Government Printer
Please cite as: de Lange, P.J. (Year at time of access): Tetrachondra hamiltonii Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/tetrachondra-hamiltonii/ (Date website was queried)