Dryas octopetala; the mountain avens is a common plant in heathers and gravely/sandy soils. It can be found almost everywhere on Iceland. It is model plant for paleobotany. Presently the species occurs in the subarctic regions and on the high mountains of central Europe and the Scottish/Welsh mountains etc.. From pollen research it is known to have been widespread through the lowlands of Europe during the glacial periods. The flowers are quite conspicuous but so are the maturing fruits with the spirally, hairy tufts of the maturing fruit (see photo of maturing fruits)
It is a member of the rose family (Rosaceae).