Ranunculus amphitrichus
Common names
waoriki
Biostatus
Native
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
Yellow
Detailed description
Perennial; rosettes tufted along creeping stems; nodes not usually bulbous. Basal leaves with slender erect or ascending petioles (20-)5-10(-150) mm long; lamina trifoliolate to palmatisect, glabrous, ± circular, 10-20 mm diameter; leaflets sessile, obtriangular, bluntly 3-fid up to ½ way, sometimes again bluntly toothed, ± equal. Leaves of flowering stems ternate with linear acute entire leaflets. Flowers 1-4(-7) per stem, 7-12 mm diameter; pedicels glabrous. Sepals spreading, glabrous. Petals (3-)4-5(-9), yellow, narrowly oblong, oblong to narrowly obovate, 2-4 mm long, shortly clawed; nectary single, 1.0-1.5 mm from petal base, with a short, tumid, semilunar scale. Receptacle with a basal collar of bristles. Achenes (6-)10-20(-30), hardly flattened, glabrous; body 1.5-2.0 mm long, obscurely wrinkled when ripe; beak straight or curved, 1.0-1.5 mm long.
Similar taxa
From R. glabrifolius Hook., R. amphitrichus is distinguished by the collar of hairs at the base of the receptacle, the completely glabrous leaves, fewer petals with different nectary scales, and usually more achenes.
Distribution
Indigenous. New Zealand (North, South, Chatham Islands). Also Australia.
Habitat
Coastal to montane. Often partially submerged in shallow water, wet grassland and lake, pond or tarn marginal turf communities. Sometimes in moist clearings within forest or tussock grassland.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened | Qualifiers: SO
Detailed taxonomy
Family
Synonyms
Ranunculus rivularis Banks et Solander ex DC. nom. illeg.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
(September-)October-January(-May)
Fruiting
October - June
Propagation technique
Easily grown from fresh seed and by the division of whole plants. An attractive plant suitable for growing on the margin of a fish pond or slow-flowing stream. It is often sold for such purposes by mainstream garden centres.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
OBL: Obligate Wetland
Almost always is a hydrophyte, rarely in uplands (non-wetlands).
Other information
Etymology
ranunculus: From the Latin ‘rana’ frog, meaning little frog and probably refers to the plants typical marshy habit where frogs abound
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.
RANAMP
Chromosome number
2n = 96
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened | Qualifiers: SO
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | Regionally Not Threatened
Referencing and citations
Attribution
Factsheet prepared by P.J. de Lange (10 February 2007). Description from fresh plants and herbarium specimens.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Ranunculus amphitrichus Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/ranunculus-amphitrichus/ (Date website was queried)