The Genera of Leguminosae-Caesalpinioideae and Swartzieae
| The Genera of Leguminosae-Caesalpinioideae and Swartzieae | |
Habit and leaf form. Trees; without tendrils; unarmed. Phyllotaxy spiral. Leaves compound; pinnate; paripinnate. Leaflets few per leaf; markedly asymmetrical at the base (rather), or symmetrical or nearly so at their bases; opposite or sub-opposite; with a strong, continuous marginal nerve; petiolulate; with markedly twisted petiolules. Stipules connate (basally, into an intrapetiolar scale; upper parts free and caducous). Stipels present (rare), or absent.
Inflorescence and floral morphology. Flowers large; hermaphrodite; not pentamerous throughout; departing from pentamery in the calyx and in the corolla, or in the calyx, in the corolla, and in the androecium; white or green, or coloured; in panicles (of racemes); not distichous. Inflorescences terminal; of racemose units. Bracts absent at anthesis. Bracteoles present; small, not enclosing the flower buds; absent at anthesis, or persistent beyond anthesis (rare); not valvate; free. Hypanthium present. Length of floral tube relative to total hypanthium plus calyx length, about 0.25 (rare), or 0.5, or 0.75 (rare). Calyx polysepalous; covering the rest of the flower in bud; more or less regular, or markedly zygomorphic; 4 partite; imbricate. Corolla present; very zygomorphic (with one large orbicular or reniform petal); including greatly reduced petals, or without any greatly reduced petals. Petals white, or white and red; 1, or 1–5 (rare). Clawed petals present (the large one). Disk absent. Androecium of fewer than ten parts, or of ten parts; with united members, or members all free of one another; members markedly unequal; with staminodia, or without staminodia. Fertile stamens 3–8. Anthers attached well above base of connective. Dehiscence longitudinal. Ovary stipitate; excentric with adnate stipe. Ovules numerous.
Fruit, seed and seedling. Fruit a two-valved pod; becoming distinctly woody; without prominent raised veins; not winged; without markedly twisting or enrolling valves. Seeds non-endospermic; arillate; with a straight or slightly oblique radicle; amyloid-positive. Cotyledons of Type 4; with a vascular system ramified throughout; epigeal.
Transverse section of lamina. Leaves with conspicuous phloem transfer cells in the minor veins. Druses common in the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders absent. Laminae dorsiventral. Mesophyll 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, or not seen. 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; medium-thin to thin. 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; scarcely staining with safranin, or staining normally with safranin; medium-thin.
Wood anatomy. Wood without septate fibres; storied, or not storied; without normal intercellular canals; without traumatic canals. Intervascular pits medium to large.
Pollen ultrastructure. Tectum reticulate; strongly irregularly coarse-reticulate. Length of colpi greater than one half pole to pole distance, or less than one half pole to pole distance. Foot layer of pollen wall smooth.
Cytology, geography, etc. Basic chromosome number, x = 12. 2n = 24. 13 species. Tropical Africa, Asia. Widely cultivated.
Tribe. Detarieae.
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: 19th October 2005. http://delta-intkey.com’.