Has been incorrectly referred to Alternanthera sessilis (L.) Roem. & Schult. by past New Zealand authors
Vascular – Native
Herbs - Dicotyledons 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 = 28
Current conservation status
The threat classification 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) – more information about this can be found on the NZTCS website 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. Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – a suggested threat classification status has not been assessed by the NZTCS panel.
2017 | Not Threatened | Qualifiers: DP, SO
Previous conservation statuses
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Indigenous. Common in Australia (where the species was described from). There is some uncertainity as to its exact status in New Zealand, and while most of the populations seen appear to be indigenous, it seems likely that at least some locations may represent independent naturalisations from Australia (see Heenan & de Lange, N.Z.J.Bot. 42: 739-745 (2004))
Coastal to lowland fertile wetlands, lake margins, river banks and around waterfalls, and in damp ground within forest, also a weed of drains, pig yards, and damp ground within urban areas
Wetland plant indicator status rating
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Perennial herb. Stems prostrate to erect, somewhat lianoid, rooting at nodes, green flushed pink, glabrous to sparsely hairy, nodes tomentose. Leaves (20-)30-80 x 6-12 mm, narrowly elliptic or lanceolate, or linear to linear oblong, light green, yellow green or glaucous flushed pink, with midrib and lateral veins pink, glabrate, apex acute, margins distinctly denticulate. Spikes globular to shortly oblong 5-8 mm diam., clustered with 15-20 flowers. Flowers subtended by 1 bract and 2 bracteoles, these 1.5-2 x 0.6-0.8 mm, lanceolate, cream, glabrous, shortly acuminate to acute. Perianthe segments 2.3-2.4 x 0.6-0.8 mm, lanceolate, cream, glabrous, shortly acuminate to acute, anthers 0.15 mm long, yellow, style 0.1-0.2 mm, stigma capitate. Fruit 1.7-1.8 x 1.9-2.1 mm, cream flushed pink, obovoid, indehiscent. Seeds 0.9-1 x 0.8-0.9 mm, cream to yellow, with a light brown centre, compressed.
Closely related to A. nahui Heenan et de Lange. From which it differs by its more gracile growth habit and by the much broader, distinctly denticulate leaves. Hybrids between A. denticulata and A. nahui have been recorded.
January - December
January - December
Urticles are dispersed by attaching to fur, feathers and clothing (Thorsen et al., 2009).
Easily grown from rooted pieces, cuttings and seed but inclined to become very weedy.
alternanthera: From the Latin alternus ‘alternate’ and the Greek anthera ‘anther’, meaning alternating anther, probably in reference to the anthers being alternately fertile and barren.
denticulata: Finely toothed
Where To Buy
Not commercially available. Rather weedy and unattractive but the leaves are eaten as a vegetable by some ethnic groups.
Description from Heenan and de Lange (2004).
References and further reading
Heenan, P.B.; de Lange, P.J. 2004: Alternanthera denticulata (Amaranthaceae) in New Zealand: a new addition to the indigenous or naturalised flora? New Zealand Journal of Botany 42: 739-745.
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 2009 Vol. 11 No. 4 pp. 285-309
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Alternanthera denticulata Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/alternanthera-denticulata/ (Date website was queried)