Acaena

Life-forms

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Rosids
Cladus: Eurosids I
Ordo: Rosales

Familia: Rosaceae
Subfamilia: Rosoideae
Tribus: Agrimonieae
Subtribus: Sanguisorbinae
Genus: Acaena
Species: A. agnipila – A. alpina – A. anserinifolia – A. antarctica – A. argentea – A. boliviana – A. buchananii – A. caesiiglauca – A. caespitosa – A. confertissima – A. cylindristachya – A. dumicola – A. echinata – A. elongata – A. emittens – A. eupatoria – A. exigua – A. fissistipula – A. fuscescens – A. glabra – A. hirsutula – A. inermis – A. integerrima – A. juvenca – A. latebrosa – A. leptacantha – A. longiscapa – A. lucida – A. macrocephala – A. macrostemon – A. magellanica – A. masafuerana – A. microphylla – A. minor – A. montana – A. myriophylla – A. novae-zelandiae – A. ovalifolia – A. ovina – A. pallida – A. patagonica – A. pinnatifida – A. platyacantha – A. poeppigiana – A. profundeincisa – A. pumila – A. rorida – A. saccaticupula – A. sarmentosa – A. sericea – A. splendens – A. stangii – A. stricta – A. subincisa – A. tenera – A. tesca – A. torilicarpa – A. trifida
Nothospecies: A. × anserovina
Name

Acaena Mutis ex L., Mant. Pl. 2: 145 (1771).

Type species: Acaena elongata L., Mant. Pl. Altera 200 (1771).

Synonyms

Heterotypic
Ancistrum J.R.Forst. & G.Forst., Char. Gen. Pl. 2: 29 (1775).
Lasiocarpus Banks & Sol. ex Hook.f., Fl. Antarct.: 264 (1846).
Sphaerula W.Anderson ex Hook.f., Fl. Antarct.: 268 (1846).

Distribution
Native distribution areas:

Continental: Europe
Regional: Northern Europe
Great Britain, Ireland (introduced).
Continental: Africa
Regional: Southern Africa
Cape Provinces.
Continental: Asia-Tropical
Regional: Papuasia
New Guinea.
Continental: Australasia
Regional: Australia
New South Wales, Queensland, South Australia, Tasmania, Victoria, Western Australia.
Regional: New Zealand
Antipodean Islands, Chatham Islands, New Zealand North, New Zealand South.
Continental: Pacific
Regional: North-Central Pacific
Hawaii (extinct).
Continental: Northern America
Regional: Northwestern U.S.A.
Oregon (introduced).
Regional: Southwestern U.S.A.
California.
Regional: Mexico
Mexico Central, Mexico Northeast, Mexico Gulf, Mexico Southwest, Mexico Southeast.
Continental: Southern America
Regional: Central America
Guatemala.
Regional: Western South America
Bolivia, Colombia, Ecuador, Peru.
Regional: Brazil
Brazil Southeast, Brazil South.
Regional: Southern South America
Argentina Northeast, Argentina South, Argentina Northwest, Chile Central, Chile North, Chile South, Juan Fernández Islands, Uruguay.
Continental: Antarctic
Regional: Subantarctic Islands
Amsterdam-St.Paul Islands, Crozet Islands, Falkland Islands, Heard-McDonald Islands, Kerguelen, Macquarie Islands, South Georgia, Tristan da Cunha.

References: Brummitt, R.K. 2001. TDWG – World Geographical Scheme for Recording Plant Distributions, 2nd Edition
References
Primary references

Linnaeus, C. 1771. Mantissa Plantarum Altera. Generum Editionis VI et Specierum Editionis II. Holmiae [Stockholm]. pp. [6] + 143­–587, Appendix. BHL Reference page.

Additional references

Macmillan, B.H. 1991. Acaena rorida and Acaena tesca (Rosaceae) - two new species from New Zealand. New Zealand Journal of Botany 29(2): 131–138. DOI: 10.1080/0028825X.1991.10416716 Reference page.

Links

Hassler, M. 2020. Acaena. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2020. Species 2000 & ITIS Catalogue of Life. Published online. Accessed: 2020 May 29. Reference page.
Govaerts, R. et al. 2020. Acaena in Kew Science Plants of the World online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2020 May 29. Reference page.
International Plant Names Index. 2020. Acaena. Published online. Accessed: 29 May 2020.

Vernacular names
čeština: Acéna
dansk: Tornnød
Deutsch: Stachelnüsschen
English: New Zealand Burr, Bidibid
suomi: Akeenat
Māori: Piripiri

Acaena is a genus of about 60 species of mainly evergreen, creeping herbaceous perennial plants and subshrubs in the family Rosaceae, native mainly to the Southern Hemisphere, notably New Zealand, Australia and South America, but with a few species extending into the Northern Hemisphere, north to Hawaii (A. exigua) and California (A. pinnatifida).[2]

The leaves are alternate, 4–15 centimetres (1.6–5.9 in) long, and pinnate or nearly so, with 7–21 leaflets. The flowers are produced in a tight globose [inflorescence] 1–2 centimetres (0.39–0.79 in) in diameter, with no petals. The fruit is also a dense ball of many seeds; in many (but not all) species the seeds bear a barbed arrowhead point, the seedhead forming a burr which attaches itself to animal fur or feathers for dispersal.

Several Acaena species in New Zealand are known by the common name bidibid. The word is written variously bidi-bidi, biddy-biddy, biddi-biddi, biddi-bid and a number of other variations. These names are the English rendition of the original Māori name of piripiri.[3] The plant is also called the New Zealand burr. The species Acaena microphylla has gained the Royal Horticultural Society's Award of Garden Merit.[4]

Etymology

The generic name Acaena is derived from the Greek "akaina" (thorn), referring to the spiny hypanthium.[5]
Species

As of 2020, Plants of the World Online accepted the following species:[6]

Acaena agnipila Gand.
Acaena alpina Poepp. ex Walp.
Acaena anserinifolia (J.R.Forst. & G.Forst.) J.B.Armstr.
Acaena antarctica Hook.f.
Acaena argentea Ruiz & Pav.
Acaena boliviana Gand.
Acaena buchananii Hook.f.
Acaena caesiiglauca (Bitter) Bergmans – glaucous pirri-pirri-bur
Acaena caespitosa Gillies ex Hook. & Arn.
Acaena confertissima Bitter
Acaena cylindristachya Ruiz & Pav.
Acaena dumicola B.H.Macmill. (South Island of New Zealand)
Acaena echinata Nees – sheep's burr
Acaena elongata L.
Acaena emittens B.H.Macmill. (North Island of New Zealand)
Acaena eupatoria Cham. & Schltdl.
Acaena exigua A.Gray – liliwai (Hawaiʻi)
Acaena fissistipula Bitter
Acaena fuscescens Bitter
Acaena glabra Buchanan
Acaena hirsutula Bitter
Acaena inermis Hook.f.
Acaena integerrima Gillies ex Hook. & Arn.
Acaena juvenca B.H.Macmill. (New Zealand)
Acaena latebrosa W.T.Aiton
Acaena leptacantha Phil.
Acaena longiscapa Bitter
Acaena lucida (Aiton) Vahl
Acaena macrocephala Poepp.
Acaena magellanica (Lam.) Vahl – greater burnet
Acaena masafuerana Bitter
Acaena microphylla Hook.f. – New Zealand-bur
Acaena minor (Hook.f.) Allan
Acaena montana Hook.f.
Acaena myriophylla Lindl.
Acaena novae-zelandiae Kirk – red bidibid (New Zealand)
Acaena ovalifolia (Vahl) Ruiz & Pav.
Acaena ovina A.Cunn.
Acaena pallida (Kirk) Allan – sand bidibid
Acaena patagonica A.E.Martic.
Acaena pinnatifida Ruiz & Pav. – Argentinian biddy-biddy
Acaena platyacantha Speg.
Acaena poeppigiana Gay
Acaena profundeincisa (Bitter) B.H.Macmill.
Acaena pumila Vahl
Acaena rorida B.H.Macmill. (North Island)
Acaena saccaticupula Bitter
Acaena sarmentosa (Thouars) Carmich.
Acaena sericea J.Jacq.
Acaena splendens Hook. & Arn.
Acaena stangii Christoph.
Acaena stricta Griseb.
Acaena subincisa Wedd.
Acaena tenera Albov
Acaena tesca B.H.Macmill. (South Island)
Acaena torilicarpa Bitter
Acaena trifida Ruiz & Pav.

Invasive species

Some species have been introduced accidentally to other areas, attached to sheep's wool, and have become invasive species. Acaena novae-zelandiae, one of the bidibids from New Zealand, is the most commonly encountered species in the United Kingdom, where it is often abundant on coastal sand dunes, crowding out native vegetation and creating an often painful nuisance with the barbed burrs. In California, A. pallida, A. novae-zelandiae and A. anserinifolia are considered serious weeds.[7]
References

"genus Acaena". Germplasm Resources Information Network (GRIN) online database. Retrieved 30 March 2020.
RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 1405332964.
Orsman, H. W. (1999). The Dictionary of New Zealand English. Auckland: Oxford University Press.
RHS Plant Selector Acaena microphylla AGM / RHS Gardening
Bryony Macmillan. "Rosaceae 26. Acaena". E-Flora (Flora of North America). Retrieved 2015-12-03.
"Acaena". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 30 March 2020.
"Weeds Sorted by Pest Rating", CFDA.ca.gov