Chenopodium detestans
Common name
New Zealand fish-guts plant
Synonyms
None
Family
Amaranthaceae
Flora category
Vascular – Native
Endemic taxon
Indeterminate
Endemic genus
No
Endemic family
No
Structural class
Dicotyledonous Herbs other than Composites
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.
CHEDET
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.
2012 | Threatened – Nationally Critical | Qualifiers: DP, EF, TO
Previous conservation statuses
2009 | Threatened – Nationally Critical | Qualifiers: TO, EF, DP
2004 | Data Deficient
Distribution
Indigenous to New Zealand, South Island only . Historically the species ranged from Canterbury to Otago. Recent (post 1980) collections have only been made from Lake Lyndon (first discovered by T. Kirk in 1877) and the upper Waitaki Valley. In those days this area was extensively farmed for sheep and cattle, and while this was the case C. detestans was common on the shores of Lake Lyndon, in sites frequented by these animals. The species has been found in New South Wales, Australia where it may have naturalised.
Habitat
Open or sparsely-vegetated ground such as clay and salt plans, dried out river and lake beds.
Features
Annual to short-lived perennial prostrate, grey-green to reddish-grey, fleshy herb forming patches up to 800 mm diameter, and arising from a stout central, deeply descending tap root. All parts strongly fetid, smelling of rotten fish. Branches 2-8, grey-green, with stems and emergent leaves often suffused with red, rather stiff, margins often distored by fungus pustules. Emergent foliage grey-farinose, maturing grey-green or reddish-grey, rather fleshy; leaves rhombic, or rhomboid-ovate, usually entire except for the basal stem leaves which often possess 1 pair of teeth, apex acute. Flowers grey-green in dense axillary to terminal spike-like clusters, stigma white. Perianth segments 4-5, 0.5-1.0 mm long, divided almost to base, obtuse, scarcely accrescent, incompletely investing fruits. Stamens 1-2 sulphur yellow, not fused at base. Seed, circular, 1-1.2 mm diameter, dark purple-brown to black brown, minutely punctate, margins rounded (obtuse), aligned horizontally in perianth.
Similar taxa
The introduced Chenopodium vulvaria (fish-guts plant) is a very similar, equally smelly plant, which can only be reliably distinguished from C. detestans by its 5 rather than 1-2 stamens, and sharp (acute) rather than rounded seed margins.
Flowering
September – March
Flower colours
Green, Grey
Fruiting
December - May
Life cycle
Seeds are dispersed by wind and water (Thorsen et al., 2009).
Propagation technique
As far as is known no one has successfully grown this species. There have been a few attempts to transplant wild plants and strike cuttings but these failed because the plants/cuttings were given to much water. Seed should germinate easily.
Threats
As far as is known C. detestans has declined mainly because of a loss of suitable open, sparsely-vegetated habitats. This seems to have been the result of the spread of introduced pasture grasses and weeds, and changes in land use, especially stocking levels. The only recent collections have come from well-stocked sheep farms in the upper Waitaki Valley, where it grows on clay and salt pans. Possibly because of its foul smell the species does not seem to be palatable to livestock, so livestock may help reduce competition from other taller, more palatable plants.
Etymology
chenopodium: From the Greek chen ‘goose’ and pous ‘foot’, referring to the shape of the leaves
Where To Buy
Not Commercially Available.
Attribution
Description based on live plants and herbarium specimens
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