Alternanthera denticulata


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

Common Name(s)

lesser joyweed

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


Alternanthera denticulata R.Br.



Flora Category

Vascular - Native

NVS Species 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.

Structural Class

Dicotyledonous Herbs other than Composites


Has been incorrectly referred to Alternanthera sessilis (L.) Roem. & Schult. by past New Zealand authors


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


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.

Similar Taxa

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

Flower Colours



January - December

Propagation Technique

Easily grown from rooted pieces, cuttings and seed but inclined to become very weedy.


Not Threatened

Chromosome No.

2n = 28

Endemic Taxon


Endemic Genus


Endemic Family


Life Cycle and Dispersal

Urticles are dispersed by attaching to fur, feathers and clothing (Thorsen et al., 2009).

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

This page last updated on 14 Aug 2014