Species

Ranunculus amphitrichus

Etymology

Ranunculus: From the Latin 'rana' frog, meaning little frog and probably refers to the plants typical marshy habit where frogs abound

Common Name(s)

waoriki

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

Authority

Ranunculus amphitrichus Colenso

Family

Ranunculaceae

Flora Category

Vascular - Native

NVS Species Code

RANAMP

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

Synonyms

Ranunculus rivularis Banks et Solander ex DC. nom. illeg.

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.

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 purpose sby mainstream garden centres.

Threats

Not Threatened

Chromosome No.

2n = 96

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

 

  

Attribution

Fact Sheet prepared by P.J. de Lange 10 February 2007. Description from fresh plants and herbaium specimens.

This page last updated on 3 Nov 2014