Acaena microphylla var. microphylla
Common names
bidibid, piripiri
Biostatus
Native – Endemic taxon
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
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Simplified description
An evergreen shiny green and or bronze herb, which forms a dense mat spreading up to ½ a metre across and about 2 cm in height. The plant is in general a small species of the genus. Found in the central North Island in unconsolidated substrates like river gravels. The pinnate leaves are sharply toothed and have tiny hairs on the tips. The globe shaped flower balls are white, on short stems then grow into a cluster of red non-barbed spikes, which when ripe brown off.
Flower colours
White
Detailed description
Rhizomatous, prostrate, trailing perennial herb, forming a mat up to 0.5 metres in diameter. Stems 1 mm diameter, up to 25 cm long, and/or 2 cm high, rooting at nodes; Stipules entire; Leaves odd-pinnate, between 5-30 mm long with 9-15 leaflets; Leaflets orbicular 1.5-4 × 1.5-4 mm, serrated blunt-toothed margin, 5-7 teeth minutely hair-tipped, lower leaflets gradually reduce in size, green or bronze shiny upper surface obvious veins, lower surface paler and sparsely hairy; Inflorescence scape 7-25 mm, bearing shaggy hairs; Capitulum about 5 mm diameter when flowering, composed of up to 20 florets, each floret has 4 sepals, 2 stamen, white anthers, 2 white styles, 2 achenes; Fruit roughly cone-shaped, each having 4 pink or crimson pointed barbless spines (occasionally no spines), up to 15 mm long, which mature dry, brown or golden brown when ripe.
Similar taxa
Acaena microphylla var. pauciglochidiata is very similar with a couple of differences, the capitula is stalkless compared to a scape of 7-25 mm in A. microphylla var. microphylla; also, the capitula has less florets 2-4, whereas A. microphylla var. microphylla has up to 20; the fruit spines are tipped with a few hairs compared to bald in A. microphylla var. microphylla.
Acaena anserinifolia a very close relative, at a glance is similar to both of the A. microphylla varieties, it does however have larger proportions in numerous aspects. The leaves can reach 75 mm in length, it has more florets than both species 50-60, a longer scape than both species 40-120 mm, and barbed spines.
Acaena rorida is similar to both of the A. microphylla varieties. Growing in only one area its range does not overlap with the nearest A. microphylla var. microphylla. Acaena microphylla has smaller, shiny green or bronze leaves; scapes are shorter 6-15 mm compared to up to 25 mm long in A. microphylla var. microphylla. The capitula has up to 10 florets, whereas A. microphylla var. microphylla has up to 20 florets.
Distribution
Endemic. Central North Island.
Habitat
Montane to low alpine (500-1300 m.a.s.l.), grassland, river terraces.
Detailed taxonomy
Genus
Family
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
November-January.
Fruiting
January-April.
Life cycle and dispersal
Spiny hypanthia are dispersed by attaching to fur, feathers and clothing and possibly also dispersed by wind and granivory (Thorsen et al., 2009)
Other information
Etymology
acaena: From the Greek ‘akanthos’ thorn, referring to the spiny calyx that many species have
microphylla: Small leaf
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.
ACAMVC
Chromosome number
2n = c.42
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
Referencing and citations
References and further reading
Allan HH. 1961. Flora of New Zealand. Volume 1. Indigenous Tracheophyta: Psilopsida, Lycopsida, Filicopsida, Gymnospermae, Dicotyledones. Government Printer, Wellington, NZ. pg. 357.
Hooker JD. 1853 The Botany of the Antarctic Voyage of H.M. Discovery Ships Erebus and Terror in the Years 1839–1843, under the command of Captain Sir James Clark Ross. II. Flora Novae-Zelandiae. Part I. Flowering plants. Lovell Reeve, London. Pg. 55.
Lee WG, Macmillan BH, Partridge TR, Lister R, Lloyd KM. 2001. Fruit features in relation to the ecology and distribution of Acaena (Rosaceae) species in New Zealand. New Zealand Journal of Ecology. 25(1): pp.17-27.
Macmillan BH. 1991. Acaena rorida and Acaena tesca (Rosaceae)—two new species from New Zealand. New Zealand Journal of Botany, 29(2): pp.131-138.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309. https://doi.org/10.1016/j.ppees.2009.06.001.
Attribution
Fact sheet prepared for NZPCN by MD Ward (August 28th 2025). Description adapted from Lloyd (2001), Allan (1961), Hooker (1853).
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.