Solitary graminoid herb forming dense tussocks from an often richly branched caudex. Leaves crowded terminally on caudex branches. Culms slender, usually nodding, up to 15–20 cm.

Leaves twisted sideways in the rosettes when seen from above, 5–10 cm long and usually less than half as long as the culm during and after flowering, 3–4 mm broad at the base, involute, margins scabrous, pale to bright green and ending in a reddish or brown curled tip.

The flower in Carex is unisexual (either male or female), without perianth, and supported by a scale (the bract of the single flower). The male flower consists of 3 stamens. The female flower consists of a gynoecium of 2 or 3 fused carpels, with a single style and 2 or 3 stigmas, and with a single seed. The gynoecium is surrounded by a perigynium, a container with a narrow apical opening through which the style and stigmas emerge. The perigynia (and nuts) are either lenticular (when two carpels/stigmas) or trigonous (when three). The inflorescences are spikes, one or more per culm. If two or more spikes, all except for the uppermost are supported by more or less leaf-like bracts. Spikes may be unisexual or bisexual, and bisexual spikes may have the female flowers at base (basigynous) or at top (acrogynous). Flowers are wind pollinated and usually cross pollinated because the male flowers reach anthesis before the female flowers (protandry). Cross pollination predominates among sedges investigated in alpine Norway (Berggren & Haugset unpubl.), either due to the protandry or to genetic incompatibility. Seeds are spread inside their perigynia.

Inflorescence of (2)3–4 nodding spikes on 0.5–1 cm long peduncles, the upper 1–2 spikes bisexual with female flowers at the top (acrogynous), the other spikes female. Bracts with long sheaths and somewhat reduced blades, usually tinged with purplish brown; lowermost bract with sheath (10)11–15(18) mm and blade 6–11(13) mm, next lowermost bract with sheath (5.5)6–9(10) mm and blade 5–9 mm. Scales acute, dark brown with white hyaline margin. Perigynia flat, scabrous at margin, apically with a 0.1–0.2 mm long bifid beak, dark reddish brown. Stigmas 2(3).

Flat or lenticular nut within the perigynium.

Sexual reproduction by seeds; no vegetative reproduction. Assumed ripe fruits did not germinate (Alsos et al. 2013) but this may be due to the general difficulties in germinating sedge fruits in laboratories. However, present distribution, structure of populations, and size of individuals suggest that the species regularly reproduces by seeds.

Fruits (inside perigynia) have no special adaptation to dispersal but are generally easily dispersed by wind, water and birds, perigynia of C. misandra perhaps especially easily by wind as they are so thin and light.

Distinct from all other Carex species in Svalbard by a combination of forming dense cushions, having relatively large, nodding spikes and the absence of a purely male spike. The only other Carex species in Svalbard with nodding spikes is the also tussocky, but very small-grown C. capillaris ssp. fuscidula, found only at the warm springs in Bockfjorden (see that species for more differences).

Usually growing as scattered tussocks among heath vegetation of Dryas octopetala and Cassiope tetragona but sometimes dominating. Fine-grained or moderately coarse substrates, usually moderately well drained or slightly moist with circumneutral to basic soil reaction (pH, Elvebakk 1982). At sheltered sites with intermediate snow cover. Probably much grazed by reindeers.

Common in the middle arctic tundra zone, occurs more scattered in the northern arctic tundra zone and barely penetrating to the polar desert zone. Common in the weakly to clearly continental sections, scattered in the transitional section. Rather common on parts of Spitsbergen and Nordaustlandet but not found on other islands. The distribution is concentrated to the areas with circumneutral or basic substrates, especially in the Isfjorden, Kongsfjorden, Liefdefjorden, and Wijdefjorden districts, and the species is very rare in the acidic south, only found a few places by Van Mijenfjorden and Van Keulenfjorden (Nordenskiöld Land, Nathorst Land).

The general range is circumpolar, mainly in the arctic zones but reaching southwards in mountains, in Europe only as far as S Norway (an isolated part range), in E Asia and W North America much farther south.

Carex fuliginosa ssp. misandra is one of the most characteristic and widespread of arctic sedges, first described from Melville Island in the Canadian Arctic Archipelago. Its only close relative is confined to the European Alps (C.fuliginosa s. str.). Many authors have claimed that there is no difference between this Alpine plant and the arctic one (e.g., Ball & Mastrogiuseppe 2002). Aiken & Elven (observ.) compared arctic plants with plants from the Alps and found some minor differences supporting acceptance of two races. However, treating ssp. misandra as an independent species (C. misandra), as previously done by the majority of authors, seems inappropriate until the differences are studied also by molecular methods; there are only few and small differences been Alpine and Arctic plants.

Alsos, I.G., Müller, E. & Eidesen, P.B. 2013. Germinating seeds or bulbils in 87 of 113 tested Arctic species indicate potential for ex situ seed bank storage. – Polar Biology 36: 819–830. Doi 10.1007/s00300-013-1307-7.

Ball, P.W. & Mastrogiuseppe, J. 2002. Carex Linnaeus sect. Aulocystis Dumortier. – In: Flora of North America Editorial Committee (eds.), Flora of North America north of Mexico. 23. Magnoliophyta: Commelinidae (in part): Cyperaceae: 477–482.

Elvebakk, A. 1982. Geological preferences among Svalbard plants. – Inter-Nord: 11–31.