The Genera of Leguminosae-Caesalpinioideae and Swartzieae
Habit and leaf form. Trees, or shrubs, or climbers or scramblers (rare); without tendrils (foliage not foetid); unarmed. Phyllotaxy spiral. Leaves compound, or simple (rare); pinnate; imparipinnate, or rare. Leaflets opposite or sub-opposite; petiolulate; with petiolules not noticeably twisted. Stipules absent or early caducous or very inconspicuous, or present, persistent and conspicuous (rare); neither leafy nor spinescent. Stipels present, or absent.
Inflorescence and floral morphology. Flowers hermaphrodite; not pentamerous throughout; departing from pentamery in the calyx, in the corolla, and in the androecium; in simple racemes, or in fascicled inflorescences (of racemes), or in panicles; not distichous. Inflorescences often at older nodes or flowering on leafless branchlets; of racemose units, or of solitary flowers (rare). Bracts absent at anthesis. Bracteoles small, not enclosing the flower buds; absent at anthesis, or persistent beyond anthesis. Hypanthium absent. Length of floral tube relative to total hypanthium plus calyx length, about 0.75–1. Calyx gamosepalous; covering the rest of the flower in bud; not imbricate; Swartzieae type (closed before flowering, splitting more or less irregularly into valvate lobes or teeth). Corolla present, or absent; very zygomorphic. Petals 1. Disk absent. Androecium of more than ten parts; with united members (rare), or members all free of one another; members markedly unequal; without staminodia. Fertile stamens 30 (or more). Anthers attached well above base of connective (dorsifixed, much shorter than the filaments). Dehiscence longitudinal. Ovary stipitate; free. Ovules numerous.
Fruit, seed and seedling. Fruit a two-valved pod, or indehiscent; becoming distinctly woody, or not becoming woody; straight. Seeds endospermic, or non-endospermic; arillate; with an inflexed radicle; amyloid-negative; with starch. Cotyledons not flat.
Transverse section of lamina. Leaves without conspicuous phloem transfer cells in the minor veins. Druses absent from the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders common (the veins transcurrent). Laminae isobilateral, with adaxial and abaxial palisades, or dorsiventral. Mesophyll exhibiting fibres or sclereids which are unaligned with the vascular bundles, or without unaligned fibres or sclereids. Minor veins mainly with abundant accompanying fibres.
Leaf lamina epidermes. Epidermal crystals not seen either adaxially or abaxially. Simple unbranched hairs common; scabrid, or smooth. No compound or branched eglandular hairs seen. Capitate glands not seen. Hooked hairs not seen. Cassieae-type leaf pseudo-glands not seen. Expanded and embedded hair-feet absent. Adaxial interveinal epidermal cell walls straight in optical section; conspicuously pitted, or not conspicuously pitted; medium-thick. Stomata adaxially very rare. Abaxial stomata predominantly paracytic. Abaxial epidermis not papillate. Abaxial interveinal epidermal cell walls straight, or gently undulating; conspicuously pitted in optical section, or not conspicuously pitted in optical section; staining normally with safranin.
Wood anatomy. Wood without septate fibres; storied; without normal intercellular canals; without traumatic canals. Intervascular pits medium to large.
Pollen ultrastructure. Tectum reticulate; rugulose reticulate. Length of colpi greater than one half pole to pole distance.
Cytology, geography, etc. Basic chromosome number, x = 8 (Africa), or 14. 135 species. Tropical America, Africa. Not widely cultivated.
Tribe. Swartzieae (Papilionoideae).
The interactive key provides access to the character list, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, and summaries of attributes within groups of taxa.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1993 onwards. The genera of Leguminosae-Caesalpinioideae and Swartzieae: descriptions, identification, and information retrieval. In English and French; French translation by E. Chenin. Version: 22nd March 2009. http://delta-intkey.com’.