''Acaena microphylla'', the bidibid or piripiri, and outside New Zealand, New Zealand-bur, is a small

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

, prostrate

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the rose family

Rosaceae Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. Among the most species-rich genera are ''Alchemilla'' (270), ''Sorbus ...

, native to both the North and South Islands of

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. There are two varieties: *''Acaena microphylla'' var. ''pauciglochidiata''

Bitter Bitter may refer to: Common uses * Resentment, negative emotion or attitude, similar to being jaded, cynical or otherwise negatively affected by experience * Bitter (taste), one of the five basic tastes Books * '' Bitter (novel)'', a 2022 nove ...

*''Acaena microphylla'' Hook.f var. ''microphylla'' There are no synonyms.

Description

Hooker describes it as "a very small and

glabrous Glabrousness (from the Latin '' glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part of ...

species; the leaflets not 1/4 in. long. ''Capitula'' very large for the size of the plant, upwards of an inch across, including the spines, which are not

barbate Barbate is a municipality of Spain part of the Province of Cádiz, in the autonomous community of Andalusia. It is coastal town located off the Atlantic Ocean, close to the Strait of Gibraltar. Displaying a total area of 142.17 km2, it ha ...

, and distinguish it as a species."

Taxonomy and naming

''Acaena microphylla'' was first formally described in 1852 by

Joseph Dalton Hooker Sir Joseph Dalton Hooker (30 June 1817 – 10 December 1911) was a British botanist and explorer in the 19th century. He was a founder of geographical botany and Charles Darwin's closest friend. For twenty years he served as director of t ...

. The

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

name ''Acaena'' is derived from the

ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

word ''akaina'', meaning "thorn" or "spine", referring to the spiny calyx of many species of ''Acaena''. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''microphylla'' derives from the Greek words, (small) and (leaf), to give an adjective meaning "small-leaved".

Distribution

It is found on both the

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...

and

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...

of New Zealand.

Conservation status

In 2013, the variety ''Acaena microphylla'' var. ''pauciglochidiata'' was classified as "At Risk - Naturally Uncommon" under the

New Zealand Threat Classification System The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand. The system was developed because the IUCN Red List, a similar conservation status system, had some ...

. By 2018, due to an actual decline, the status changed to "At Risk - Declining". (The

area of occupancy Area is the quantity that expresses the extent of a region on the plane or on a curved surface. The area of a plane region or ''plane area'' refers to the area of a shape or planar lamina, while '' surface area'' refers to the area of an open s ...

had decreased to 100 km² or less, and the predicted decline was 10 to 50%). However, the variety ''Acaena microphylla'' var. ''microphylla'' was classified as "Not Threatened" in 2004, 2009 and 2012, and again in 2018.

References

External links

''Acaena microphylla'' occurrence data
from

Australasian Virtual Herbarium The ''Australasian Virtual Herbarium'' (AVH) is an online resource that allows access to plant specimen data held by various Australian and New Zealand herbaria. It is part of the Atlas of Living Australia (ALA), and was formed by the amalgamat ...

* {{Taxonbar, from=Q9572126 microphylla Flora of New Zealand Taxa named by Joseph Dalton Hooker Plants described in 1852