Flora of the Canadian Arctic Archipelago
English: Pea family.
Fabaceae (Leguminosae), Pea family.
Vegetative morphology. Plants 1–50 cm high; perennial herbs (ours); caespitose (sometimes loosely), or not caespitose; glandular viscid, or not glandular viscid. Taproot present. Ground level or underground stems horizontal, or absent; rhizomatous; elongate; 0.4–0.8 mm wide (if applicable). Ground level or underground stems scales absent (stipules present). Caudex present, or absent. Aerial stems branching from a tap at or near ground level into two or more branches; erect (usually), or ascending, or decumbent. Aerial stem trichomes appressed, or spreading. Leaves mainly basal, or distributed along the stems; alternate, or opposite (appear opposite in compact plants); dying annually and non-persistent, or marcescent. Stipules present; persisting for 2 or more years; (2–)3–30 mm long; 0.2–8 mm wide; sheathing, or not sheathing; brown, or green, or white, or colourless, or black from hairs; hairy; pubescent, or pilose, or villous, or long-silky, or strigose; apex acuminate, or acute, or rounded, or obtuse. Petioles 5–170 mm long; glabrous, or hairy; pilose, or villous, or tomentose, or long-silky, or strigose. Petiole hairs shorter than the diameter of the petiole, or longer than the diameter of the petiole; appressed, or spreading, or erect, or reflexed; straight, or curved; smooth. Leaf blades compound. Blades (7–)15–120 mm long, 3–60 mm wide (usually, to 130 mm wide palmate Lupinus leaf blades), spreading, veins pinnate or with inconspicuous veins. Blade adaxial surface dull or shiny, with sessile glands or without sessile glands, glabrous or glabrescent or hairy, hairs pubescent or pilose or villous or short-silky or long-silky or strigose, hairs simple, hairs sparse or moderately dense or dense, hairs white, or translucent. Blade abaxial surface glabrous or glabrescent or hairy, hairs pubescent or pilose or villous or short-silky or long-silky or strigose, hairs sparse or moderately dense or very dense, hairs white or a mixture of white and yellow, hairs straight or curved or wavy, hairs appressed or spreading. Blade margins flat or slightly revolute. Blade apices acuminate, or acute, or obtuse, or rounded. Leaflet arrangement palmate, or pinnate, or digitate (in Lupinus). Leaflets (3–)7–33; (1.5–)5–60 mm long; 0.5–11 mm wide; linear, or oblong, or elliptic, or ovate, or lanceolate, or oblanceolate; veins conspicuous, or veins inconspicuous.
Reproductive morphology. Flowering stems about as high as the leaves, or conspicuously taller than the leaves; without leaves. Flowering stems hairy. Flowering stems pilose, or villous, or tomentose, or long-silky, or strigose. Flowering stem hairs simple, or branched; shorter than the diameter of the flowering stem, or longer than the diameter of the flowering stem; white or translucent, or black. Flowers solitary, or in inflorescences (usually). Inflorescences spicate, or racemose (appearing spicate by reduction or suppression of pedicels, rarely with a single flower), or head-like; terminal; dense, or diffuse; oblong, or globose or sub-globose; 0.5–15 cm long; 10–45 mm wide; elongating as the fruit matures, or not elongating as the fruit matures. Pedicels present, or absent. Bisexual spike(s) with empty bracts at the base (stipule-like). Floral scales hairy all over, or hairy mainly at apex. Flowers per inflorescence 1–30; medium-sized, or large; bilaterally symmetrical (zygomorphic). Sepals conventional; 5; fused; 3–10 mm wide; green, or yellow, or brown, or purple, or black, or pink; herbaceous, or scarious. Calyx tubular (usually), or funnel-form; 5-lobed (usually); hairy. Calyx hairs pilose, or villous, or long-silky, or strigose; glandular, or non-glandular; white or translucent, or brown. Calyx teeth equal or nearly so, or sub-equal or unequal; without or with few glandular verrucae, or with abundant glandular verrucae; 0.8–5.5 mm long. Petals conventional; both free and fused; 5; green, or white, or yellow, or orange, or pink, or purple, or blue; with contrasting markings (colour gradation and insect guidelines), or without contrasting markings; unlobed (four petals), or slightly lobed or undulating (banner petal); 6–30 mm long. Corolla papilionaceous (the largest and uppermost petal, called the banner, is bilobed, the two lateral ones that are similar, are called wings, and below and partly enclosed by them is the keel, formed by two petals united along the lateral margin petals); keel blunt, or with a pointed tip. Wing auricles free from each other, blunt, shorter than the claw, or united, linear, nearly equal to the claw. Stamens 10. Anther filaments 9 fused into a tube, plus 1 free. Anthers yellow; 0.3–0.6 mm long. Nectaries present. Ovary superior; carpels 1; monomerous. Stipes 0–8 mm long. Stigmas per ovary 1. Ovules per ovary 2–30. Fruit sessile, or stalked; with calyx persisting; dry; a legume, or a loment; spherical (almost), or ellipsoid, or ovoid, or elongate-cylindrical, or obovate, or oblong; yellowish, or black, or brown, or red, or green at maturity; 5–40 mm long; 2–10 mm wide; glabrous, or hairy, or glabrescent; distinctly flattened, or not distinctly flattened; dehiscent, or indehiscent; splitting to the base into separate segments, or opening at the apex and partially or fully down one side. Legume unilocular, or nearly 2-locular by intrusion of placenta; valves twisted, or straight. Loment margins wingless, or winged with auricles. Styles persisting but not modified (sometimes persisting, thread-like at the tip of the legume). Seeds 1–25; 1–6 mm long; black, or brown, or yellowish; surfaces smooth.
General notes. Key to genera from Porsild (1964).
1. Leaves palmate...Lupinus
1. Leaves pinnate... 2
2. Legumes flat, indehiscent, composed of several articulate sections... Hedysarum
2. Legumes subcylindrical, dehiscent... 3
3. Keel of corolla blunt, without appendage at tip....Astragalus
3. Keel of corolla tipped with an erect point...Oxytropis
Illustrations. • Anthers. Arrangement of anthers in all arctic members of the Fabaceae. • Infrutescences of Astragalus and Oxytropis. Difference in structure of infrutescence of Astragalus (alpinus) and Oxytropis (campestris subsp. sordida). Finland, Kuusamo, Kiutakongas. 27 August, 1983. Photograph by R. Elven. Legume fruits characteristic of members of the genera Astragalus and Oxytropis. • Distinctive stipules. Contrasting stipules at the base of compound leaves. Left, Oxytropis maydelliana; centre, Astralagus eucomus; right, Astragalus alpina. 2005. Photograph by Kathy Thornhill.
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..