The Genera of Leguminosae-Caesalpinioideae and Swartzieae
| The Genera of Leguminosae-Caesalpinioideae and Swartzieae | |
Habit and leaf form. Trees, or shrubs (rare); without tendrils; unarmed. Phyllotaxy spiral. Leaves compound; pinnate; paripinnate. Leaflets few per leaf; markedly asymmetrical at the base, or symmetrical or nearly so at their bases; opposite or sub-opposite; without a continuous marginal nerve; petiolulate; with petiolules not noticeably twisted. Stipules absent or early caducous or very inconspicuous, or present, persistent and conspicuous; leafy, or neither leafy nor spinescent. Stipels absent.
Inflorescence and floral morphology. Flowers medium-sized; hermaphrodite; pentamerous, or not pentamerous throughout; departing from pentamery in the corolla, or in the androecium, or in the corolla and in the androecium; white or green; in simple corymbs, or in panicles; not distichous. Inflorescences terminal (on the branchlets). Bracts absent at anthesis (caducous, leathery). Bracteoles present (spathulate); relatively large and enclosing the flower buds; absent at anthesis; valvate. Hypanthium present. Length of floral tube relative to total hypanthium plus calyx length, about 0.5. Calyx polysepalous; 5 partite; imbricate; not Swartzieae type. Corolla present; very zygomorphic (upper petals larger, hooded and folded in bud, 2–4 lower ones small and linear or absent); polypetalous; including greatly reduced petals, or without any greatly reduced petals. Petals white; 1–5. Clawed petals present. Disk absent. Androecium of ten parts; with united members (9 basally united, 1 free); members markedly unequal; without staminodia. Fertile stamens 10. Anthers attached well above base of connective. Ovary stipitate; excentric with adnate stipe. Stigma not peltate (the style filiform). Ovules numerous.
Fruit, seed and seedling. Fruit a two-valved pod; becoming distinctly woody; curved; with prominent, raised veins; with veins other than the longitudinal ones predominating; not winged; valves twisting and enrolling during dehiscence. Seeds with a straight or slightly oblique radicle; amyloid-positive. Cotyledons epigeal.
Transverse section of lamina. Leaves with 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), or 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; 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 present, or absent; all medium to thick-walled; hair feet (at least some of them) complex with vertical walls. Basally bent hairs present. Adaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; not conspicuously pitted; thin. Stomata adaxially very rare. Abaxial stomata predominantly paracytic. Abaxial epidermis papillate interveinally, or not papillate; with papillae over-arching the stomata. Abaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; not conspicuously pitted in optical section; staining normally with safranin; medium-thin to thin.
Wood anatomy. Wood without septate fibres; not storied; without normal intercellular canals; with traumatic canals. Intervascular pits medium to large.
Pollen ultrastructure. Tectum punctate, or striate; smooth punctate, or puncticulate; pole to pole striate. Length of colpi greater than one half pole to pole distance.
Cytology, geography, etc. Basic chromosome number, x = 12. 2n = 24. 15 species. Africa. Tropical Africa. Not widely cultivated.
Tribe. Detarieae (Amherstieae of Cowan and Polhill 1981).
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’.