Acaena glabra
Common names
bidibid, piripiri
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Simplified description
An evergreen shiny bright green herb, which grows in clumps up to a 1/2 metre across and about 15cm in height. The pinnate leaves are delicate and blunt-toothed, and may have a reddish, contrasting coloured margin. The globe shaped flower balls are white in bloom and grow into a cluster lacking noticeable spikes, which when ripening become orangish/red, then brown off.
Flower colours
Green, Red/Pink, White
Detailed description
Woody rootstock not more than 10 mm diameter, spreading or upright or both, trailing perennial herb, forming a tight clump up to 50 cm in diameter. Stems 1-3 mm diameter, hairy, 5-15 cm long, and/or 5-15 cm high, rooting at nodes; Stipules entire, trifid, quadrifid or occasionally pentafid; Leaves odd-pinnate, between 20-70 mm long with 9-13 leaflets; Leaflets ovate with narrowing base, 4-6 × 6-9 mm channelled, deeply serrated blunt-toothed margin, 7-9 teeth per leaflet often red not hair-tipped, lower leaflets smaller, upper surface bright green and shiny, lower surface dull light green; Inflorescence scape 30-90 mm, glabrous; Capitulum of more than 100 florets, each floret has 4 sepals, 2 stamen, white (occasionally red) anthers, 1 white style, 1 achene; Fruit roughly wedge-shaped, each having 2 barbless spines enclosed in hypanthium wings, occasionally protruding up to 2 mm.
Similar taxa
Acaena anserinifolia, a widespread stoloniferous rather than rootstock species that may be similar at a vegetative stage, only when no seed heads are present as they are markedly different. Leaflets are hair tipped and underside very hairy, covered in silvery hairs which give this species a more grey-green appearance rather than bright green as seen in A. glabra.
Acaena novae-zelandiae, a widespread stoloniferous species rather than rootstock that may be similar at a vegetative stage, only when no seed heads are present as they are markedly different. Leaflets are shiny and bright green and mostly glabrous have up to 15 teeth per leaflet compared to up to 9 in A. glabra.
Distribution
Endemic. Eastern South Island, Marlborough to North Otago.
Habitat
Montane to alpine (600-1750 m.a.s.l.), shingle and scree margins.
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
Detailed taxonomy
Genus
Family
Taxonomic notes
In Webb et. al. (1988) it is recorded that a single specimen collected in the Ida Valley had red anthers rather than the standard white.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
December-January
Fruiting
January- March
Life cycle and dispersal
Spiny hypanthia are dispersed by wind (Thorsen et al., 2009)
Other information
Etymology
acaena: From the Greek ‘akanthos’ thorn, referring to the spiny calyx that many species have
glabra: Hairless
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.
ACAGLA
Chromosome number
2n = 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
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Otago: 2025 | Regionally At Risk – Regionally Naturally Uncommon | Qualifiers: DPR, DPS, DPT, NR, NS, Sp
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Conservation Status of Indigenous Vascular Plants in Otago, 2025” Jarvie S et al. (2025) report.
Referencing and citations
References and further reading
Lloyd K. 2001. A Key and notes for Acaena (Rosaceae) in New Zealand. Botanical Society of Otago Newsletter 25. Pgs.10-14.
Mark AF. 2012. Above the Treeline: A Nature Guide to Alpine New Zealand. Craig Potton Publishing, Nelson. pg. 112.
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.
Webb CJ, Sykes WR, Garnock-Jones PJ. 1988. Flora of New Zealand, Volume IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. Botany Division, Department of Scientific and Industrial Research, Christchurch, NZ. Pg. 1060.
Attribution
Fact sheet prepared for NZPCN by MD Ward (August 29th 2025). Description adapted from Mark (2012), Lloyd (2001), Webb et. al. (1988).
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.