Leptinella nana
Common names
pygmy button daisy
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Herbs - Dicotyledonous composites
Flower colours
Green, Yellow
Detailed description
Diminutive, much-branched, monoecious, perennial herb forming small, diffuse patches. Rhizomes at soil surface, slender, 0.5 mm diam., green, sparsely pilose hairy. Leaves 1-several at apex, mostly distant. Leaves 1-pinnatifid, 4-20 x 0.2-0.4 mm; blade 0.3-15 mm, obovate to narrow-obovate, membranous, green usually without brown pigmentation, glabrous or sparsely pilose hairy, pinnae 6-10 pairs,distal ones close-set or overlapping, proximal ones distant; teeth 0-3 on distal margins of proximal pinnae. Peduncles shorter than leaves, 0.3-10 mm, glabrous to pilose. Capitula 1-2 mm diam, yellow, surface convex, involucre hemispherical; phyllaries 20 in 2 subequal rows, oblong or obovate, red-green, villous, with wide, brown-tipped, scarious margins. Pistillate florets 20-30, staminate 5-7 both in 2 rows, c.1 mm long, straight, yellow-green; corolla equal in length and width. Achenes 1 x 0.5 mm, ovoid, green-brown.
Similar taxa
Easily distinguished from all other indigenous, small-leaved, diminutive Leptinella species by the branches which radiate from a central cluster, rhizome leaves crowded at the apex, short shoots absent or reduced, leaf bases, phyllaries and florets which lack dark veins; and by the slender rhizomes up to 0.5 mm diam, membranous leaves, and yellow-green capitula up to 2 mm diam.
Distribution
Endemic. North and South Islands. In the North Island it is only known from the south western coastline at one site near Titahi Bay. In the South Island it is known from two sites, one at the Rai Valley, Marlborough and the other near Mount Pleasant, in the Port Hills, near Christchurch, Canterbury.
Habitat
Habitat varies from forest to coastal and montane cliff-top grassland, but common features are the need for disturbance patches, shelter, and supply of moisture. The species appears to have adopted a strategy of constant colonisation of small patches of bare ground and so occupies a highly dynamic and changing micro-habitat.
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 Endangered | Qualifiers: Sp, CD, DPT, EF
Threats
Likely factors in any local extirpation of L. nana include loss of temporary open sites for colonisation, increased competition from other plants, opening up of protective vegetation allowing sites to dry out or become weedy, increased erosion or deposition of debris, excessive trampling by people and animals, loss of seed dispersal vectors like terrestrial birds and other animals, seed loss to unsuitable habitat, and indiscriminate herbicide use. Slugs are a threat to cultivated L. nana.
Detailed taxonomy
Family
Asteraceae
Synonyms
Cotula nana D.G.Lloyd
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
Early Spring to end of October and early autumn to early winter
Fruiting
Through out the year
Life cycle and dispersal
Papery cypselae are dispersed by wind and possibly attachment (Thorsen et al., 2009).
Propagation technique
Easy from rooted pieces and often self sows and establishes in gardens. As it is very small it is easily lost by being over-topped by taller plants. Does best in permanently open ground. An ideal plant, once established for high impact areas, though it seems to prefer a damp soil to do best.
Other information
Plant of the Month
This plant has been featured as a Plant of the Month – see Trilepidea: NZPCN newsletter for January 2016 for the full story.
Etymology
leptinella: From the Greek word leptos (meaning slender, thin or delicate), referring to the ovary
nana: Small
Chromosome number
2n = 52
Previous conservation statuses
2017 | Threatened – Nationally Critical | Qualifiers: CD, DP, EF, Sp
2012 | Threatened – Nationally Critical | Qualifiers: CD, EF, Sp
2009 | Threatened – Nationally Endangered | Qualifiers: CD, EF, Sp
2004 | Threatened – Nationally Endangered
Referencing and citations
References and further reading
Lloyd, D.G. 1972: A revision of the New Zealand, Subantarctic, and South American species of Cotula, section Leptinella. New Zealand Journal of Botany 10: 277-372.
Moss, T.C. 1985. Observations on Cotula nana Lloyd. Wellington Botanical Society Bulletin, 42: 64-67
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.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (31 August 2006). Description from Lloyd (1972) - as Cotula nana.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Leptinella nana Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/leptinella-nana/ (Date website was queried)