Kingdom:  Plantae
Subkingdom: Tracheobionta
Superdivision:  Spermatophyta
Division:  Magnoliophyta
Class:  Magnoliopsida
Order: Ranunculales
Family: Ranunculaceae
Genus:  Ranunculus
Species: R. reflexus
Binominal name: Ranunculus reflexus
Common names: Hairy buttercup, Maru, Maruru, Kopukapuka, Pirikau

Ranunculus reflexus is an endemic perennial rosette forming buttercup that grows up to 40 cm tall along track sides and open shade in lowland and subalpine bush. It grows throughout New Zealand.
The hairy leaflets are on 10 cm stalks and can be deeply lobed.  During spring and summer 10 mm diameter, 5 petalled, yellow flowers appear.  Later the seeds form in the centre of each flower and ripen from mid-spring to mid-autumn. The plant is self-seeding.

The early Maori use this plant used for a toothache, inflamed eyes and abrasions. 

Photographed at Te Kainga Marire Gardens, New Plymouth.
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The lobed leaflets.
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Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/