Flora of the Canadian Arctic Archipelago

DELTA
Home

S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, L.J. Gillespie, A.K. Brysting, H. Solstad, and J.G. Harris

Carex gynocrates Wormskjold, in Drejer

English: Northern bog sedge,

French: Carex des glaces, Carex à côtes,

Inuktitut: Iviit, ivisuka, ivitsuskaka.

Cyperaceae, Sedge family.

Published in Naturhist. Tidsskr. 3: 16. 1841.

Type: Described from Greenland: "Egalik Bay".

Synonymy. Carex dioica L. subsp. gynocrates (Wormskjold) Hultén, Circump. Pl. 1: 170. 1962.

Carex alascana Boeck., Bot. Jahrb. Syst. 7: 277. 1886.

Vegetative morphology. Plants (2–)4–15(–30) cm high; perennial herbs; not caespitose (stoloniferous). Only fibrous roots present. Roots pallid-brown. Ground level or underground stems horizontal; stoloniferous; compact (thread-like). Ground level or underground stems scales absent. Aerial stems erect (sterile stems often prostrate or with a curved base); filiform (0.5–0.8 mm in diameter). Leaves mainly basal; alternate; marcescent. Petioles absent. Sheaths present; persisting; not forming a conspicuous build-up at the base of the plant; greyish brown, or green; sheath collars absent. Ligules present; membranous. Leaves grass-like. Blades 40–80(–150) mm long, 0.3–0.7(–1.5) mm wide, straight, linear, flat or bristle-like or involute (loosely so; narrow leaves have a relatively distinct cross section), veins parallel. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blade margins scabrous (scaberulous); apices acuminate.

Reproductive morphology. Plants dioecious (very rarely), or monoecious (usually). Flowering stems circular or oval in cross section. Flowering stems about as high as the leaves (usually), or conspicuously taller than the leaves; without leaves. Leaf or reduced bract subtending the base of the inflorescence absent. Inflorescences spicate (either staminate and linear (12%), pistillate and cylindrical (74%), or staminate above and pistillate beneath (14%); pistillate spike with 4–15(-18) flowers, transversely broadly oblong to ovoid-oblong or oblong); 0.5–1.4 cm long; 1.5–7 mm wide (staminate spikes 1.5–2 mm; pistillate spikes (3-)4–7(-8) mm). Cladoprophylls absent. Inflorescence unispicate. Individual spike(s) erect (when pistillate, more or less densely 4–15(-18) flowered, 5–14 m long × 4–8 mm wide). Terminal spike completely staminate, or staminate at the apex (8–16 mm long). Floral scales shorter than the perigynium in fruit; orange-brown (uniformly so, or); with margins and sometimes midvein paler in colour than the adjacent area of the scale (translucent); ovate; 2–2.5 mm long; 1.3–1.7 mm wide; glabrous. Flowers unisexual. Staminate flowers conspicuous (when present as a completely staminate spike). Perianth represented by a perigynium. Stamens present (staminate flowers), or absent (pistillate flowers); 3. Anthers 2.3–2.7 mm long. Ovary superior; carpels 3; syncarpous. Perigynia sessile. Styles 2; partially fused; slender, extending beyond the beak. Stigmas per ovary 2. Placentation basal. Ovules per ovary 1. Fruit surrounded by a perigynium. Perigynia with a slit running down the beak on the abaxial side through which the style protrudes; broadly ovate; 2.5–2.9(–3.4) mm long; 1.2–1.7 mm wide; spreading at maturity (divergent or slightly deflexed); golden brown; membranous; surface glossy; glabrous; strongly veined, or faintly veined (with 17–20 striate); not keeled (marginal ribs seldom prominent); apices beaked with a short beak (0.5 mm long, margins glabrous or sparsely scabrid); apex oblique, becoming slightly bidentate. Fruit sessile; dry; an achene; indehiscent. Achenes lenticular; filling the perigynia. Seeds 1; 1.5–1.7 mm long (1–1.2 mm wide).

Chromosome information. 2n = 48, 50, and 70.

2n = 48 and 50.

2n = 48. Löve (1954); Löve and Solbrig (1965, central Canada); Löve (1981d, central Canada); Jørgensen et al. (1958, Greenland); Löve and Ritchie (1966, northern Canada); Yurtsev and Zhukova (1978a);

2n = 50. Zhukova and Tikhonova (1971, Chukotka); Zhukova and Petrovsky (1975, western Chukotka, 1977);

2n = 70. Zhukova and Petrovsky (1980, western Chukotka).

Ecology and habitat. Substrates: wet meadows (in springy places with Sphagnum); imperfectly drained moist areas; with high organic content, peat; calcareous.

North American distribution. Alaska, Yukon, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago limited. Rare. Low Arctic. Arctic islands: Baffin (Kimmirut, Isortoq River).

Northern hemisphere distribution. Amphi-Beringian (broadly), or North American. Taimyr – Severnaya Zemlya, Kharaulakh, West Chukotka, South Chukotka, East Chukotka, West Alaska, North Alaska – Yukon, Central Canada, Labrador – Hudson Bay, West Greenland.

General notes. Polunin (1940) noted that this sedge varies greatly in appearance according to the stage of development of the fruits, which seem to be produced in relatively small numbers.

Porsild (1957) mapped one record from Kimmirut. Since then a collection from Isortoq River (69° 56'N, 76° 50'W) is a significant extension of the known range. This suggests the species should be looked for at other locations on Baffin Island.

Cochrane (2002) noted that opinions differ about the taxonomic rank of this taxon, which is from North America and Siberia. He suggests that since it is only weakly distinguished from the the Eurasian C. dioica subsp. dioica, perhaps it is better segregated as Carex dioica subsp. gynocrates as treated by Hultén (1962). The Eurasian taxon has chromosome counts of 2n = 52 and 60, and tends to be less strongly dioecious, with paler pistillate scales and ventrally more convex perigynia.

Carex ×langeana, the hybrid between C. gynocrates and C maritima, might be looked for where the two species co-occur. (Cochrane 2002, p 301) notes that C. ×langeana [=C. dutillyi O'Neill and Duncan] "strongly resembles C. maritima; the leaves are slightly scabrous-roughened toward the apex; the heads are smaller, ellipsoid to ovoid-oblong and only 3–5 mm thick; the perigynia are appressed-ascending and more or less flat; and the achenes are not well developed. Carex ×langeana is reported as forming close turf on dry, peaty limestone barrens in Newfoundland (M.L. Fernald 1933, 1950) and as occasional upon humid rocks and coastal fens along Hudson Bay (J. Deshaye and J. Cayouette 1988). The hybrid should be expected where the parents coexist and has been reported from some of those areas (J. Cayouette and P.M. Catling 1992)" .

Illustrations. • Herbarium specimen. Loosely tufted unispicate sedge with ground-level horizontal stems and filiform aerial flowering stems lacking leaves. Nunavut, Baffin Island, Kimmirut. 27 August, 1936. N. Polunin 2341. CAN 19068. • Close-up of staminate inflorescence. Linear staminate spike at anthesis. CAN 19160. • Close-up of pistillate inflorescence. Immature pistillate spike with perigynia, having two stigmas per style. CAN 19158. • Close-up of pistillate inflorescence. Mature pistillate spike with perigynia spreading at right angles to the main stem. CAN 19157. • Arctic Island Distribution.


This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.

Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.

Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa.

.

Contents