Kobresia simpliciuscula (Wahlenb.) Mack.
Bull. Torrey Bot. Club, 50: 349. 1923.
Carex simpliciuscula Wahlenb.
Kobresia caricina Willd.
Kobresia simpliciuscula var. americana Duman.
Plants caespitose (tightly). Plants less than 15 cm high, or more than 15 cm high; 3–20(–25) cm high. Roots pallid-brown, or black. Ground level or underground stems not developed horizontally or vertically. Scales absent. Aerial stems erect; not filiform (0.5–1 mm in diameter); circular or oval in cross section; glabrous. Leaves mostly basal. Sheaths reddish (brown). Ligules present. Blades straight; linear; folded, or caniculate; glabrous. Blades adaxial surface glabrous.
Plants monoecious. Flowering stems about as high as the leaves, or conspicuously taller than the leaves. Leaf or reduced bract closely associated with the base of the inflorescence absent. Inflorescence spicate; linear (rarely), or ovate; 0.8–1.5 cm long; 3–10 mm wide; multispicate; 2–7 spikes (few flowered, secondary spikes contracted into a lax head-like inflorescence, in tall specimens the lowermost spike is somewhat remote); lateral spikes sessile (or almost so). Individual spike(s) erect, or ascending. Terminal spike staminate at the apex. Staminate flowers inconspicuous. Floral scales orange brown; with margins, and sometimes mid-vein paler in colour than the adjacent area of the scale, or with margins paler than body of scale (margins hyaline, midvein distinct almost to the tip); acute (apex obtuse to sub-acute); lanceolate; 2.3–2.6 mm long; 1.3–1.7 mm wide; glabrous. Perianth absent. Anthers (1–)1.3–1.6(–2) mm long. Styles long and thick (black and longer than the floral scales); 1. Stigmas per style 3. Fruit surrounded by a perigynium. Perigynia open on one side; lanceolate, or broadly ovate; 1.9–2.3 mm long; 0.8–1.2 mm wide; sessile; erect or ascending; brown; surface dull; glabrous; appearing nerveless; apices without a beak. Fruit 0.6–2 mm long; yellowish (brown towards the tip). Achenes not filling the upper part of the perigynia; lenticular.
Chromosome information. 2n = 70–75.
Distribution. Circumpolar. Arctic, or alpine. Range in the Canadian Arctic Archipelago wide-spread. Arctic Islands: Baffin, Devon, Ellesmere, Victoria, and Southampton.
Ecology and habitat. Substrate around the margins of ponds, marshes, river terraces, tundra, slopes (rocky), sea shore (on tidal flats); imperfectly drained, or on seepage slopes, or dry; calcareous; rock, gravel, till; with low organic content, or with high organic content, or peat (older, dry). Typically local and rare. Found in marshes with Carex rariflora and C. capillaris, on seepage slopes with Trichophorum caespitosum and Saxifraga aizoides, and on dry peaty tundra with Dryas.
Notes. Polunin (1940) observed that K. simpliciuscula prefers less dry and exposed places than does K. myosuroides, often growing in quite damp meadows among grasses. It grows most frequently to about 12 cm high but sometimes exceeds 25 cm or, in unfavourable situations may be reduced to 4 cm. It is markedly calciphilous, but probably not obligately so Polunin (1940). It is often badly smutted.
Illustrations. • Close-up of inflorescence. Inflorescence with conspicuous lateral spikes which distinguishes this species from Kobresia myosuroides. • Arctic Island distribution.
Cite this publication as: Aiken, S.G., Boles, R.L., and Dallwitz, M.J. 1999 onwards. ‘Cyperaceae of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval.’ Version: 6th November 2000. http://http://www.mun.ca/biology/delta/arcticf/. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
