Ranunculus amphitrichus
Common name
waoriki
Synonyms
Ranunculus rivularis Banks et Solander ex DC. nom. illeg.
Family
Ranunculaceae
Flora category
Vascular – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledons 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.
RANAMP
Chromosome number
2n = 96
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.
Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Not Threatened | Qualifiers: SO
Previous conservation statuses
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
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.
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).
OBL: Obligate Wetland
Almost always is a hydrophyte, rarely in uplands (non-wetlands).
Features
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.
Flowering
(September-)October-January(-May)
Flower colours
Yellow
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.
Etymology
ranunculus: From the Latin ‘rana’ frog, meaning little frog and probably refers to the plants typical marshy habit where frogs abound
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)