Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Eudicots
(Unranked): Rosids
Order: Rosales
Family: Rosaceae
Subfamily: Rosoideae
Tribe: Sanguisorbeae
Subtribe: Sanguisorbinae
Genus: Acaena
Species: Acaena microphylla 
Common names: Scarlet Piripiri, Rosy Spined New Zealand Burr

Acaena microphylla is a prostrate branching herb perennial which forms a 1m dense carpet of green to bronze-green leaves with a height of 3 cm. The leaves are up to 3cm in length.
In December to March when in bloom, the bright red coloured, burr-like flower-heads (2.3cm in diameter) form bright red patches which can last until April.
Found in the wild in grasslands, riverbeds and herb fields of the Volcanic Plateau in the Tongariro National Park up to 1,100m altitude.

The Royal Horticultural Society has given Acaena microphylla their prestigious Award of Garden Merit which is for plants of outstanding excellence. It can be purchased from specialised nurseries.

Photographed at Otari Wilton Bush Reserve.
Photo showing bronze-green leaves.and burr-like flower-heads. Photo taken March after long dry summer
Acaena microphylla Scarlet Bidibid -002.JPG 

A close of a burr-like flower-head. (March.)
Acaena microphylla Scarlet Bidibid -001.JPG 

The developed burr with hooks.Acaena microphylla Scarlet bidibid-002.JPG

Acaena microphylla Scarlet bidibid-005.JPG 

A developing flower head (November)Acaena microphylla scarlet bidibid-006.JPG

Acaena microphylla Scarlet bidibid-001.JPG 

Thanks to Wikipedia for text and information: