Flora of the Canadian Arctic Archipelago
| Flora of the Canadian Arctic Archipelago | |
Cyperaceae, Sedge family.
Published in In Novosti Sist. Vyssh. Rast. 10: 104. 1973.
Type: Alaska: Kussiloff, 07.1898, leg. W.H. Evans 725 (?). Fragment of type in S.
Synonymy. Carex lugens Holm, Amer. J. Sci., ser. 4, 10: 269. 1900.
Carex ensifolia (Gorodkov) Holub subsp. lugens (Holm) Vorosch., in A.K. Skvortsov, Florist. Issl. v Razn. Raionakh SSSR, 154. 1985.
Carex yukonensis Britton, in Britton and Rydberg, Bull. New York Bot. Gard. 2: 159. 1901.
Carex consimilis Holm, Amer. J. Sci., ser. 4, 10: 269. 1990. Type: Canada: Yukon territory, Klondike, Indian Divide, leg. J. Macoun 53878. Holotype: CAN.
Vegetative morphology. Plants (8–)15–35(–40) cm high; perennial herbs; caespitose; in dense single compact tufts (forming rather large tussocks). Only fibrous roots present. Roots pallid-brown. Ground level or underground stems horizontal, or vertical (elongated stems sometimes tending to be vertical rather than horizontal); rhizomatous; elongate (not always present on herbarium specimens). Ground level or underground stems scales present. Aerial stems erect; not filiform (1–1.6 mm in diameter). Leaves present; mainly basal; alternate; marcescent. Petioles absent. Sheaths present; persisting; forming a conspicuous build-up at the base of the plant; brown, or reddish orange; sheath collars absent. Ligules present. Leaves grass-like. Blades 40–220 mm long, 1–2 mm wide, straight, linear, flat or revolute or folded, veins parallel, not septate nodulose (distinguishing this species from C. aquatilis). Blade abaxial surface scabrous (scaberulous on the midrib and margins). Blade margins scabrous (scaberulous at the tip); apices acuminate.
Reproductive morphology. Plants monoecious. Flowering stems two or more per plant. Flowering stems triangular in cross section. Flowering stems conspicuously taller than the leaves; with leaves. Leaf or reduced bract subtending the base of the inflorescence present; reduced, or scale-like; shorter than the apex of the inflorescence (usually); 7–32 mm long; persistent; sheathless. Inflorescences a spike of spikes (short pedicels present, easily overlooked); oblong, or ovate (pistillate spikes), or linear (staminate spike); 2–5 cm long; 10–20 mm wide. Pedicels scabrous. Cladoprophylls present. Inflorescence multispicate. Inflorescence 3–4 spikes. Individual spike(s) erect (lateral spikes pistillate, 2–30 mm long × 3–4 mm wide). Terminal spike completely staminate (the proximal spike densely flowered, base cuneate, less often attenuate). Floral scales shorter than the perigynium in fruit, or as long as the perigynium in fruit; black (purplish); with margins and sometimes midvein paler in colour than the adjacent area of the scale (margins hyaline, midvein narrow and green); not reflexed (spreading at maturity); ovate; 2–3.5 mm long; 1–2 mm wide; glabrous. Flowers unisexual. Staminate flowers conspicuous. Perianth represented by a perigynium. Stamens present (staminate flowers), or absent (pistillate flowers); 3. Anthers 2.5–3 mm long. Ovary superior; carpels 3; syncarpous. Perigynia sessile. Stipes 0.01–0.15 mm long. Styles 2; partially fused; thick and short. Stigmas per ovary 2. Placentation basal. Ovules per ovary 1. Fruit surrounded by a perigynium. Perigynia fused to the apex except for a small aperture through which the style protrudes; broadly ovate; 2.5–3 mm long; 1.4–1.8 mm wide; erect or ascending; black (at maturity, or pale purplish mottled with green towards the base, uniformly purple-brown at the rounded apex); membranous; surface dull; glabrous; papillose (strongly or minutely); appearing veinless; not keeled; apices merely conical or rounded. Fruit sessile; dry; an achene; indehiscent. Achenes lenticular; filling the perigynia. Seeds 1.
Chromosome information. 2n = 60, 70–76, 80.
2n = 60. Zhukova (1965a, eastern Chukotka);
2n = 70–76. Johnson and Packer (1968, northwestern Alaska, as C. bigelowii);
2n = 80. Zhukova and Petrovsky (1972, 1976, western Chukotka); Yurtsev and Zhukova (1978, eastern Chukotka); Petrovsky and Zhukova (1978).
Ecology and habitat. Substrates: marshes, river terraces, tundra (shrubby or marshy); imperfectly drained moist areas; silt, till; peat (older deposits), with high organic content; calcareous (moderately to imperfectly drained). On riverbanks, along streams, and in marshy or shrubby tundra: a major consistuent of 'tussock tundra' in Alaska.
North American distribution. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, continental Nunavut (?). Range in the Canadian Arctic Archipelago limited. Rare. Low Arctic. Arctic islands: Banks (Sachs Harbour and Masik River, the latter is a new record since Porsild, 1957), Victoria (Prince Albert Sound and Holman).
Northern hemisphere distribution. Amphi-Beringian. Anabar–Olenyok, Kharaulakh, Yana–Kolyma, West Chukotka, Wrangel Island, South Chukotka, East Chukotka, West Alaska, North Alaska – Yukon, Central Canada.
General notes. Standley et al. (2002) recognised this taxon at the subspecies level in the Flora of North America treatment and keyed out the two subspecies as follows:
"Perigynia green, spotted purple-black on apical half, minutely papillose; stipe 0.15–0.45 mm long, proximal pistillate spike loosely flowered, base often attenuate, less often cuneate... C. bigelowii subsp. bigelowii.
Perigynia green, often white at maturity, uniformly purple-brown on apical half, stongly or minutely papillose; stipe 0–0.15 mm long, proximal pistillate spike densely flowered, base cuneate, less often attenuate...C. bigelowii subsp. lugens." (p. 400)
Standley et al. (2002) note that several floras recognise two species, C. lugens and C. consimilis, in the western Arctic and that these species have more affinities to eastern Asian taxa than to eastern C. bigelowii. "These treatments usually separate C. lugens by the caespitose habit, leaves less than 2 mm wide, and setaceous proximal bract. Careful study of the complex indicates that although there are caespitose and rhizomatous morphs, leaf width, bract width, perigynium size and shape all vary considerably within and between populations and the variation is not correlated with habit. It is not known whether variation in habit is due to genetic differences or merely to plant responses to differences in substrate and soil moisture. Long-rhizomatous plants tend to occur in dry tundra, and short-rhizomatous plants tend to occur in wet, peaty muskeg. For that reason, the group is recognised as a single taxon that needs further study.’
Elven (personal communication, 2005) noted that some initial AFLP data (Schönswetter, unpublished) support the fact that C. lugens should be included in C. bigelowii s.l., preferably as a subspecies, but that it also should include several Eurasian entities described as species and subspecies by Russians.
Schaefer and Messier (1995), in a study of scale-dependent correlations of arctic vegetation and snow cover in southeastern Victoria Island, found that C. bigelowii exhibited positive associations with various measures of snow cover. It is thought that snow cover may reduce the rate of desiccation, protect plants from abrasion, and insulate them from low temperatures.
Illustrations. • Close-up of herbarium specimen. Note coarse rhizome with persistent reddish sheaths. Uppermost culm leaf shorter than the multispicate inflorescence. N.W.T., Eskimo Lake Basin. 23 July, 1947. A.E. Porsild 16768. CAN 25144. • Close-up of young inflorescence. Note short leaf subtending the inflorescence. Floral scales and perigynia almost uniformly dark brown at the apex. Terminal spike and one lower spike staminate at the apex. Stigmas 2. N.W.T., Eskimo Lake Basin. 23 July, 1947. A.E. Porsild 16768. CAN 25144. • Close-up of inflorescence. Note short leaf subtending the inflorescence, floral scales and perigynia almost uniformly dark brown, terminal spike staminate. N.W.T., Eskimo Lake Basin. 23 July, 1947. A.E. Porsild 16768. CAN 25144. • 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.
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