The genera of Leguminosae-Caesalpinioideae & Swartzieae
Type species: L. africana (Baill.) Aubrév.
Habit and leaf form. Trees, or shrubs; unarmed.
The leaves compound; pinnate; paripinnate. The leaflets few per leaf (2–4 jugate); opposite or sub-opposite; petiolulate; markedly asymmetrical to symmetrical or nearly so; pinnately veined, with a predominant midrib; with a strong, continuous marginal nerve, or without a continuous marginal nerve. Stipules membranous. Stipels absent.
Inflorescence and floral morphology. The inflorescences axillary (often on old wood); unbranched, or branched; with flowers crowded in short simple racemes, or panicles. The flowers not distichous. Bracts small, caducous, absent at anthesis. Bracteoles present; small, not enclosing the flower buds; absent at anthesis; not valvate; free.
The flowers hermaphrodite; not pentamerous throughout; departing from pentamery in the calyx; coloured. Hypanthium present; conical to cylindrical. The perianth comprising distinct calyx and corolla. Calyx 4 (the broad lobes reflexing); covering the rest of the flower in bud; not Swartzieae type; polysepalous; more or less regular; members imbricate. Corolla present; regular, or slightly irregular; 5; without greatly reduced members; polypetalous. Petals sessile; imbricate; white and yellow, or red. Disk absent. The androecium comprising 10 members; tending to declinate; with united members (basally only), or members all free of one another; members all more or less equal in length; comprising only fertile stamens. Fertile stamens 10. Anthers attached well above the base of the connective; dehiscing longitudinally. Ovary stipitate; eccentric, with the stipe adnate. Stigma not dilated (on the long, filiform style). Ovules numerous.
Fruit, seed and seedling. Fruit a two-valved pod. The mature valves without prominent venation. Seeds not arillate. Cotyledons of Type 4; with a vascular system in one plane.
Transverse section of lamina. Leaves with conspicuous phloem transfer cells in the minor veins. Druses common in the mesophyll, or absent from the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders absent. Laminae dorsiventral. Mesophyll exhibiting fibres or sclereids which are unaligned with the vascular bundles. Minor veins mainly with abundant accompanying fibres.
Leaf lamina epidermes. Epidermal crystals not seen either adaxially or abaxially. Simple unbranched hairs not seen. No compound or branched eglandular hairs seen. Capitate glands not seen. Expanded and embedded hair-feet absent. Adaxial: Adaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; not conspicuously pitted; of medium thickness. Stomata adaxially very rare. Abaxial: Abaxial stomata predominantly paracytic. Abaxial epidermis not papillate. Abaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; not conspicuously pitted in optical section; staining normally with safranin; thin.
Species number and distribution. 1–3 species (depending on inerpretation: L. africana, L. bequaertii and L. romii). Tropical Africa.
Tribe. Detarieae; Amherstieae clade of Bruneau et al. (2008).
Miscellaneous. Illustrations: • L. africana (as Schotia humboldtioides): Engler, Pflanzenwelt Afrikas (1910). • L. africana: Aubréville, Flore du Gabon (1968). • L. bequaertii (as Schotia): Leonard, in Fl. du Congo Belge (1952). • L. bequaertii, flower and fruit (Cowan & Polhill, 1981). • L. bequaertii, e.m. scanned pollen (Graham & Barker, 1981).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classification. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1993 onwards. The genera of Leguminosae-Caesalpinioideae and Swartzieae: descriptions, illustrations, identification, and information retrieval. In English and French. Version: 22nd March 2017. delta-intkey.com/caes’.