The World Flora Online

Fls regular, hypogynous or nearly so, mostly perfect and 5-merous; sep commonly united to form a tube with valvate lobes, or sometimes much-reduced; pet distinct or often connate below to form a tube, valvate; stamens as many or more often twice as many as the pet, or numerous, the anthers small, the filaments distinct or connate below, commonly colored and exserted to form the most conspicuous part of the infl; pistil 1, simple; fr a legume; seed-coat commonly with a horseshoe-shaped groove on the flat surface near the margin; embryo large, generally straight; endosperm in most genera wanting or very scanty; herbs or more often woody plants with alternate, stipulate, usually bipinnately compound lvs and numerous small fls in heads, spikes, or dense racemes. 50–60/3000. Fls perfect, slightly to evidently perigynous; sep mostly 5, ± connate into a lobed, often bilabiate tube; cor typically papilionaceous and consisting of 5 pet, the uppermost one (the standard or banner) external to the others and usually the largest; rarely, as in Centrosema and Clitoria, the fl resupinate, with the banner lowermost; 2 lateral pet, called wings, similar inter se and distinct or sometimes lightly adherent in a small area to the keel; 2 lowermost pet innermost, similar inter se, mostly connate distally to form a keel enfolding the stamens and pistil; seldom (Amorpha) only the banner present, the other pet suppressed; stamens (5–)10, most often 9 of the filaments connate into an open sheath around the pistil, the 10th (uppermost) one partly or wholly separate from the other 9 (stamens then said to be diadelphous), or less often all the stamens connate by their filaments to form a closed (or adaxially split) sheath (stamens then said to be monadelphous), or (Aeschynomene) the stamens diadelphous and 5 + 5, the sheath cleft above and below, or the filaments sometimes all distinct; pistil 1, simple; fr a legume, typically dry and dehiscent on both sutures, but sometimes indehiscent and even jointed, rarely fleshy; embryo large, the short hypocotyl-radicle typically bent back against the thickened cotyledons; endosperm mostly wanting or very scanty; herbs or less often woody plants, with alternate, stipulate, pinnately or less often palmately compound (or trifoliolate), seldom unifoliolate or simple lvs that typically have a basal pulvinus; fls borne in racemes or spikes or heads or seldom in panicles, often large and showy. 440/12,000. Fls perfect or sometimes unisexual, slightly to evidently perigynous; sep mostly 5, distinct or nearly so, or the 2 upper ones ± connate, imbricate or rarely valvate, sometimes reduced; cor of (0–)5 distinct, imbricate, similar or more often ± dissimilar pet, but not papilionaceous, the uppermost pet generally internal to the 2 upper lateral ones and often smaller than them, stamens (1–)10(-numerous), distinct or with the filaments variously connate, but not usually forming a sheath around the pistil, and not long-exserted, all alike or variously unlike, sometimes some of them staminodial; pistil 1, simple; fr a legume, sometimes indehiscent; embryo large, straight, endosperm mostly wanting or very scanty; herbs or more often woody plants, with alternate, stipulate, pinnately or less often bipinnately compound lvs (seldom unifoliolate or simple) that typically have a pulvinus at the base of the lf and at the base of each lfl, and with small to often large and showy fls mostly in racemes or spikes. 150/2000. Fls perfect, slightly to evidently perigynous; sep mostly 5, ± connate into a lobed, often bilabiate tube; cor typically papilionaceous and consisting of 5 pet, the uppermost one (the standard or banner) external to the others and usually the largest; rarely, as in Centrosema and Clitoria, the fl resupinate, with the banner lowermost; 2 lateral pet, called wings, similar inter se and distinct or sometimes lightly adherent in a small area to the keel; 2 lowermost pet innermost, similar inter se, mostly connate distally to form a keel enfolding the stamens and pistil; seldom (Amorpha) only the banner present, the other pet suppressed; stamens (5–)10, most often 9 of the filaments connate into an open sheath around the pistil, the 10th (uppermost) one partly or wholly separate from the other 9 (stamens then said to be diadelphous), or less often all the stamens connate by their filaments to form a closed (or adaxially split) sheath (stamens then said to be monadelphous), or (Aeschynomene) the stamens diadelphous and 5 + 5, the sheath cleft above and below, or the filaments sometimes all distinct; pistil 1, simple; fr a legume, typically dry and dehiscent on both sutures, but sometimes indehiscent and even jointed, rarely fleshy; embryo large, the short hypocotyl-radicle typically bent back against the thickened cotyledons; endosperm mostly wanting or very scanty; herbs or less often woody plants, with alternate, stipulate, pinnately or less often palmately compound (or trifoliolate), seldom unifoliolate or simple lvs that typically have a basal pulvinus; fls borne in racemes or spikes or heads or seldom in panicles, often large and showy. 440/12,000. Fls perfect or sometimes unisexual, slightly to evidently perigynous; sep mostly 5, distinct or nearly so, or the 2 upper ones ± connate, imbricate or rarely valvate, sometimes reduced; cor of (0–)5 distinct, imbricate, similar or more often ± dissimilar pet, but not papilionaceous, the uppermost pet generally internal to the 2 upper lateral ones and often smaller than them, stamens (1–)10(-numerous), distinct or with the filaments variously connate, but not usually forming a sheath around the pistil, and not long-exserted, all alike or variously unlike, sometimes some of them staminodial; pistil 1, simple; fr a legume, sometimes indehiscent; embryo large, straight, endosperm mostly wanting or very scanty; herbs or more often woody plants, with alternate, stipulate, pinnately or less often bipinnately compound lvs (seldom unifoliolate or simple) that typically have a pulvinus at the base of the lf and at the base of each lfl, and with small to often large and showy fls mostly in racemes or spikes. 150/2000.

Trees, shrubs, or herbs, sometimes climbing or decumbent, very often bearing root-nodules that harbor nitrogen-fixing bacteria. Leaves alternate or rarely opposite, pinnate or bipinnate, less often palmately compound or 3-foliolate, seldom 1-foliolate or simple, or modified into narrow phyllodes; petiole present or absent; stipules and stipels present or absent, sometimes stipules developed into spines. Flowers bisexual, rarely unisexual, actinomorphic (Mimosoideae), ± zygomorphic (Caesalpinioideae) to very zygomorphic (Papilionoideae), mostly in racemes, corymbs, spikes, heads, or panicles. Sepals (3-)5(or 6), free or connate into a tube, sometimes bilabiate, rarely reduced or obsolete. Petals (0-)5(or 6), usually isomerous with sepals, seldom fewer or none, imbricate or valvate, distinct and often highly differentiated into papilionaceous corolla: upper petal (standard) outermost, 2 lateral petals (wings) ± parallel with each other, lower 2 innermost petals usually connate by their lower margins and forming a keel. Stamens mostly 10, sometimes fewer or more numerous, distinct or often connate by their filaments to form a closed or open sheath, monadelphous or diadelphous, anther 2-locular, opening lengthwise or by pores, uniform or dimorphic and then alternately basifixed and dorsifixed; pollen simple or compound. Gynoecium nearly always of a solitary carpel (rarely 2 or more distinct carpels); ovary superior, 1-locular or sometimes transversely, rarely longitudinally septate; ovules 1 to numerous, inserted on adaxial suture. Legumes dehiscent by one or both sutures, or indehiscent, sometimes winged, sometimes jointed and breaking up into 1-seeded segments. Seeds without or with very scanty endosperm, sometimes strophiolate.