Carex rariflora; The Mountain Bog-sedge can be recognized by the drooping female spikes below the non-drooping male spike. This species is quite common on Iceland, both in lowland regions but even more so in highland areas. It grows in marshy terrains.
There are some other sedge species which resemble the Mountain Bog-sedge, also mid-sized sedges with drooping female spikes. These are the Tall Bog-sedge (Carex paupercula) which can be identified by the leaves: the upper leaf exceeds the male spike, and the Common Bog-sedge (Carex limosa) which has longer (more flowers) female spikes with brown scale rather than black. Another rather similar species is the Hair Sedge (Carex capillaris. This species (C. capillaris) can be recognized by the rather long pointed beaks of the utricles where they are rather blunt and small in all other mentioned species.
Coming back to the Mountain Bog-sedge (C. rariflora): another trait by which this species can be recognised are the light midribs on the dark scales of the utricles.
The Mountain Bog-sedge (C. rariflora) is a member of the sedge family (Cyperaceae). The Icelandic name of this species is Hengistör.