Flora of the Canadian Arctic Archipelago
English: Arctic lupin,
Fabaceae (Leguminosae), Pea family.
Published in Proc. Amer. Acad. Arts 8: 526. 1873.
Type: Canada: Northwest Territory, Bear Lake, Richardson, selected by W.W. Eggleston. Lectotype: GH.
Synonymy. Lupinus nootkatensis Donn var. kjellmannii Ostenf., Vidensk-Selsk. Skr., Math.-Naturv. Kl. 8. 1910. Type: King Point, Yukon, Ostenfeld, 1908. Isotype: CAN.
Lupinus yukonensis Greene, BPH: Leafl. Bot. Observ. 2: 233. 1912. Type: Klondike River, Yukon, Macoun, 9 July 1902. Isotype CAN.
Lupinus toklatensis A. Nels., Amer. J. Bot. 32: 288. 1945. Type: Alaska, Toklat area (63°31'N, 150°02' W), Mile 56, Mt. McKinley Park, Alaska, A. and R. Nelson 3568, RM, US.
Lupinus gakonensis C.P. Smith, Sp. Lup. 649. 1949. Type: Gakona, Alaska, Anderson 8532, ISC.
Lupinus multicaulis C.P. Smith, Sp. Lup. 649. 1949. Type: Glenn Highway, Alaska, Anderson in 1944, ISC.
Lupinus donnellyensis C.P. Smith, Sp. Lup. 654. 1949. Type: Donnelly Dome, Richardson Highway, mile 253, Alaska, Anderson 2281, ISC.
Lupinus multifolius C.P. Smith, Sp. Lup. 660. 1949. Type: Kluane Lake, Yukon, Anderson 9449, ISC.
Synonymy from Dunn and Gillett (1966).
Vegetative morphology. Plants 10–40(–50) cm high; perennial herbs; not caespitose. Taproot present. Ground level or underground stems vertical. Caudex present (stout). Aerial stems erect. Aerial stem trichomes appressed. Leaves mainly basal and distributed along the stems; alternate; dying annually and non-persistent (leaf blades), or marcescent (petioles). Stipules present; persisting for 2 or more years; 3–10 mm long; 1–2 mm wide (at widest point); not sheathing (but adnate to the base of the petiole); brown; hairy; strigose; apex acuminate. Petioles (50–)100–170 mm long; hairy; strigose. Petiole hairs shorter than the diameter of the petiole, or longer than the diameter of the petiole; appressed; straight. Leaf blades compound. Blades (20–)30–70 mm long, 40–130 mm wide, spreading, veins pinnate. Blade adaxial surface fresh green, hairy, hairs strigose, hairs simple, hairs sparse, hairs white, or translucent. Blade abaxial surface hairy, hairs strigose, hairs moderately dense, hairs a mixture of white and yellow, hairs straight or curved, hairs appressed (mostly). Blade margins flat. Blade apices acute. Leaflet arrangement palmate, or digitate (dark green). Leaflets 3–7(–9); 10–60 mm long; (5–)6–10(–11) mm wide; oblanceolate.
Reproductive morphology. Flowering stems without leaves. Flowering stems hairy. Flowering stems long-silky, or strigose. Flowering stem hairs branched; longer than the diameter of the flowering stem; white or translucent. Inflorescences racemose; diffuse; 3–15 cm long; 35–45 mm wide; elongating as the fruit matures. Floral scales hairy all over (strigose stipules at the base of each pedicel). Flowers per inflorescence (5–)10–30; medium-sized, or large; bilaterally symmetrical (zygomorphic) (usually arising between two stipules on the rachis). Sepals conventional; 5 (in two sections); fused; 5–6.5 mm wide; black (with white hairs); scarious. Calyx tubular (at base); 5-lobed; hairy. Calyx hairs long-silky, or strigose; white or translucent. Calyx teeth equal or nearly so; 3.5–5.5 mm long (longer than the fused portion of the calyx). Petals conventional; both free and fused; 5; white (rarely), or purple, or blue (usually); with contrasting markings (contrasting pink colour on the banner petals); unlobed, or slightly lobed or undulating (banner petal); 10–15 mm long. Corolla papilionaceous; keel blunt. Stamens 10. Anther filaments 9 fused into a tube, plus 1 free. Nectaries present. Ovary superior; carpels 1; monomerous. Stigmas per ovary 1. Ovules per ovary 13–15. Fruit stalked; with calyx persisting; dry; a legume; ellipsoid; green at maturity (a dark olive green, or blackish); 20–30 mm long; 6–9 mm wide; hairy (with black hairs); not distinctly flattened; dehiscent. Legume valves twisted (strongly in dehisced fruit). Styles persisting but not modified. Seeds (3–)5–10; 4–6 mm long; black (with white flecks seen at 10×); surfaces smooth.
Chromosome information. 2n = 48, or 96.
2n (6x) = 48. Holmen (1962, Alaska); Hedberg (1967, Alaska, 2n = about 48); Johnson and Packer (1968, northwestern Alaska); Dawe and Murray, in Löve (1979, Alaska);
2n (12x) = 96. Porsild et al. (1967, northwestern America); Packer and McPherson (1974, northern Alaska, 2n = about 96).
Ploidy levels recorded 6x and 12x.
Ecology and habitat. Substrates: wet meadows, tundra, slopes, ridges; imperfectly drained moist areas, moderately well-drained areas; sand, moss. The habitat of this plant varies from mossy sedge flats to low ridges in the Arctic islands to grassy alpine slopes further south.
North American distribution. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut. Range in the Canadian Arctic Archipelago limited. Uncommon. Low Arctic. Arctic islands: Victoria.
Northern hemisphere distribution. North American (American Beringian). West Alaska, North Alaska Yukon, Central Canada, Labrador Hudson Bay.
General notes. There have been no nomenclatural disputes about the name of this species. Subsp. arcticus is the only one extending into the Arctic islands. There are two other subspecies occurring in southern British Columbia and south into Washington. In the Arctic islands, the Arctic lupin is usually found on well-drained hummocks in the tundra, but it has occasionally been collected in sedge meadows. Further south, near the Arctic Circle, it is found in forest clearings. Lupinus arcticus is closely related to L. perennis L.
Majak et al. (1994), studying alkaloid distribution in two species of Lupinus, did not have data for the arctic subspecies, but found that L. arcticus subsp. subalpinus had sparteine, beta-isiosparteine, and multiflorine as the major alkaloids.
Illustrations. • Habitat, with author J.M. Gillett. Author J.M. Gillett sitting among lupins. N.W.T., Tuktoyaktuk. 21 July, 1981. J.M. Gillett 18726. CAN. • Plant habit. Plants growing on dry hillside with Castilleja. Note the palmate leaves. N.W.T., Tuktoyaktuk. 21 July, 1981. J.M. Gillett 18726. CAN. • Close-up of inflorescence. Close-up of inflorescence showing petals with contrasting markings and stigmas projecting through the tip of the keel petals. N.W.T., Tuktoyaktuk. 21 July, 1981. J.M. Gillett 18726. CAN. • Inflorescence with developing fruit. Inflorescence with developing hairy legumes. N.W.T., Tuktoyaktuk. 21 July, 1981. J.M. Gillett 18726. CAN. • Close-up of fruits. Legumes that have split open lengthwise into two valves that have subsequently twisted. N.W.T, Sans Sault Rapids. CAN 4017. • 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..