Fabaceae Lindley
Pea family.
Plants herbs; perennial herbs (ours); with single unbranched stems, or cushion-like, or with leaves or spreading stems arising from a caudex; 1–50 cm high; not vegetatively proliferating by bulbils; without milky juice; glandular viscid, or not glandular viscid. Taproot present. Aerial stems erect (usually), or decumbent; not conspicuously jointed; not filiform; glabrous, or sparsely hairy, or densely hairy. Branches not glaucous; epidermis not flaky. Leaves mostly basal, or distributed along the stems; alternate, or opposite (appear opposite in compact plants); not distinctly distichous; compound; not heterophyllous; deciduous, or marcescent. Stipules present; leaf-like, or scale-like; sheathing, or not sheathing; brown, or green, or white, or colourless. Petioles present; 3–60 mm long. Blades 1–12 cm long; 3–60 mm wide; herbaceous; with pinnate veins, or with inconspicuous veins; glabrous, or hairy; with hairs on the adaxial surface only, or with hairs on the abaxial surface only, or with hairs equally dense on both surfaces. Blades adaxial surface dull, or shiny. Leaf margins entire; glabrous. Conspicuous hydathodes absent. Leaflet arrangement trifoliate, or pinnate, or digitate (in Lupinus); leaflets (3–)7–33; leaflets 1.5–60 mm long; leaflets linear, or oblong, or elliptic, or ovate, or lanceolate; veins conspicuous, or veins inconspicuous.
Forming flowers and fruit. Plants bisexual. Flowering stems 0.5–25 cm long; with leaves, or without leaves; glabrous, or hairy (usually). Flowering culm nodes not rooting at the lower nodes. Flag leaf sheaths not inflated. Leaf or reduced bract closely associated with the base of the inflorescence without calloused tip. Flowers solitary, or in inflorescences (usually). Inflorescence racemose (or appearing spicate by reduction or supression of pedicels, rarely with a single flower); terminal; 0.1–15 cm long; without bulbils. Bisexual spike(s) without empty bracts at the base. Inflorescence without involucral bracts. Flowers per inflorescence 1–30; small, less than 5 mm in diameter or length, or medium-sized, 5–15 mm in diameter or length, or large, more than 15 mm in diameter or length; bisexual; zygomorphic. Floral scales not reflexed; not falling early; glabrous (usually with ciliate margins), or hairy all over. Callus not differentiated. Perianth present. Calyx present; sepals 5; sepals fused; green, or yellow, or brown, or black; herbaceous, or scarious; hairy; non-accrescent; tubular (usually), or funnel-form; 5-lobed (usually). Calyx teeth equal or nearly so, or subequal or unequal; without or with few glandular verrucae, or with abundant glandular verrucae. Petals present; 5; both free and fused; green, or white, or yellow, or orange, or pink, or purple, or blue; with contrasting markings (colour gradation and insect guide lines); unlobed (four petals), or 2-lobed (banner petal); not tipped with an awn-like bristle; 6–30 mm long; not spurred; longer than the calyx. 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 marginpetals). Wing auricles free from each other, blunt, shorter than the claw, or united, linear, nearly equal to the claw. Stamens 10; filaments all equal in length; free of the corolla. Nectaries in bisexual flowers present. Carpels monomerous. Gynoecia superior. Stipes 0–8 mm long. Styles present. Styles base not enlarged, continuous with the achene. Stigmas per style 1. Placentation axile. Ovules 2–30. Fruit not surrounded by a perigynium; with calyx persisting; a legume, or a loment; spherical (almost), or ellipsoid, or ovoid, or elongate-cylindrical, or distinctly flat, or obovate, or oblong; 5–40 mm long; 2–10 mm wide; sessile, or stalked; dry; dehiscent, or indehiscent; yellowish, or black, or brown, or green at maturity; glabrous, or hairy, or glabrescent. Legume unilocular, or nearly 2-locular by intrusion of placenta; valves twisted, or straight. Loment margins wingless, or winged with auricles. Styles style may persist until dehiscence but is not modified (sometimes persisting, thread-like at the tip of the legume). Seeds 1–25; 1–6 mm long; black, or brown; smooth.
Chromosome information. 2n = 14, 16, 28, 32, 48, 96, 97.
Distribution. Circumpolar, or amphi-Beringian, or North American, or not circumpolar, amphi-Atlantic, amphi-Beringian, or North American. Northern hemisphere: Canada. Arctic Islands: Baffin, Parry Islands, Banks, Victoria, Southampton, Coats.
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 subcylindric, dehiscent... 3
3. Keel of corolla blunt, without appendage at tip... Astragalus
3. Keel of corolla tipped with an erect point... Oxytropis.
Represented in our area by Astragalus, 3 species, Hedysarum, 2 species, Lupinus arcticus L., and Oxytropis 8 species.
Miscellaneous. Species in world 12000, genera in world 650. Genera in study region: Astragalus, Hedysarum, Lupinus, Oxytropis.
Classification. Subclass Dicotyledonae. Dahlgren’s Superorder Fabiflorae, Order 1 1. Fabales. Cronquist’s Subclass Rosidae, Order Fabales. Takhtajan’s Subclass Rosidae, Superorder Rosanae, Order Fabales.
Cite this publication as: J.M. Gillett, L.L. Consaul, S.G. Aiken and M.J. Dallwitz (1999 onwards). ‘Fabaceae of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval.’ Version: 15th 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).