Ranunculus viridis
Biostatus
Native
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
Green, Yellow
Detailed description
Perennial herb forming rosettes 80-100 mm diameter, or compact patches up to 300 mm diameter. Rhizome stout, 4-8 mm diameter, apex covered in long persistent, fibrous petiolar remnants; roots numerous, fleshy 1.5 mm diameter. Petiole 15-30 mm long, base broadly sheathing, covered in fine cobwebbed hairs, deeply grooved on upper surface. Leaves 20-40 mm diameter, bright green above paler beneath, both surfaces very glossy, deltoid to orbicular or sub-reniform, thick and rigidly firm, lamina divided about 3/4 of the way into the 3-5-lobed segments, sparsely hairy, lobe apices surmounted by a penicillate hair tuft. Flowers 25-30 mm diameter, solitary intially on very short peduncles; these elongating at fruiting to c.30-50 mm length and broadening toward apex; ebracteate, green, usually purple-stained at base, clad in fine, cobwebbed hairs. Flowers with 5 sepals, these 15 mm long, greenish-yellow, finely hairy beneath, glabrescent above, broadly oblong-obovate, apices emarginate; petals 5 not or scarcely exceeding sepals, 10-12 x 6-8 mm, basal third green otherwise bright yellow, oblong to oblong-obovate, apex cucullate, base abruptly narrowed; nectary comprising 3 pits per petal with the central pit the largest; receptacle glabrescent, pale yellow-green. Fruiting head compact, 12 mm diameter, globose to ovoid. Achenes numerous, 1.9-2.6 mm long, semi glossy brown, obovate to broadly obovate, beak straight, tapering, 2-2.6 mm long.
Similar taxa
Part of a small group of alpine ranunculi, with which species it shares some broad similarities with R. pinguis and R. sericophyllus. Ranunculus pinguis and R. viridis both have somewhat similar sparingly pilose to glabrous leaves, broad leaf segments and rather short petals which taper toward the base. Ranunculus viridis resembles R. sericophyllus in having penicillate hair tufts on the leaf segments and apices; the presence of fine cobwebbed hairs on the petiole bases and scapes, deeply divided leaves, broad petals, and especially by the 3 nectary pits. In some respects it is intermediate between both these species, but as it is allopatric from both and forms a stable, true breeding population, its claim to species rank seems clear. In other respects it is close to R. recens from which it differs by the flexible, softly hairy, rather than rigidly brittle, sparsely, stiffly hairy leaves; by the presence of penicillate hair tufts on the leaf segment apices (absent in R. recens); scapes 20 cf 10 mm long; brown rather than red straight rather than hooked achenes. It is allopatric from R. recens which On Stewart Island is a coastal species found only on sandy beaches and dune systems.
Distribution
Endemic. Stewart Island, Tin Range
Habitat
Subalpine (c.700 m a.s.l.) in damp shaded sites, on ledges, hollows, crevices and clefts of rock outcrops in subalpine scrub.
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.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- 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 | Threatened – Nationally Critical | Qualifiers: OL
Threats
This species is an extremely narrow-range endemic, which so far is only known from a very small area on the upper slopes of Mt Allen, on the Tin Range.
Detailed taxonomy
Family
Ranunculaceae
Synonyms
None
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
December - March
Fruiting
December - May
Propagation technique
Unknown from cultivation. However, likely to be rather difficult to maintain.
Other information
Etymology
ranunculus: From the Latin ‘rana’ frog, meaning little frog and probably refers to the plants typical marshy habit where frogs abound
viridis: From the Latin viridis ‘green’
Previous conservation statuses
2017 | Threatened – Nationally Critical | Qualifiers: DP, OL
2012 | Threatened – Nationally Critical | Qualifiers: DP, OL
2009 | Threatened – Nationally Critical | Qualifiers: DP, OL, St
2004 | Range Restricted
Referencing and citations
References and further reading
de Lange, P.J.; Heenan, P.B.; Norton, D.A.; Rolfe, J.R.; Sawyer, J.W.D. 2010: Threatened Plants of New Zealand. Canterbury University Press, Christchurch.
Wilson, H.D.; Garnock-Jones, P. J. 1983: Taxonomic notes on Stewart Island Ranunculus including two new species. New Zealand Journal of Botany 21: 341-345.
Attribution
Fact Sheet prepared for the NZPCN by P.J. de Lange 14 April 2006. Description adapted from Wilson & Garnock-Jones (1983) - see also de Lange et al. (2010).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Ranunculus viridis Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/ranunculus-viridis/ (Date website was queried)