The genera of Leguminosae-Caesalpinioideae & Swartzieae
Cynometra leptantha Harms
Type species: L. leptanthum (Harms) J. Léonard.
Habit and leaf form. Trees; unarmed.
Phyllotaxy spiral. The leaves compound; pinnate; paripinnate (bijugate). The leaflets few per leaf; opposite or sub-opposite; petiolulate; with markedly twisted petiolules; symmetrical or nearly so (with slight asymmetry); pinnately veined, with a predominant midrib; without a continuous marginal nerve. Stipules absent or early caducous or very inconspicuous in mature leaves (very caducous); membranous; connate (intrapetiolar). Stipels present (minute).
Inflorescence and floral morphology. The inflorescences basally with numerous imbricate bud scales, axillary and terminal; unbranched; short simple racemes. The flowers not distichous. Bracts small, scarious, caducous, absent at anthesis. Bracteoles present; small, not enclosing the flower buds; membranous, not petaloid, absent at anthesis; not valvate; sub-opposite, free.
The flowers small; hermaphrodite; not pentamerous throughout; departing from pentamery in the calyx. Floral tube length relative to total hypanthium + calyx length about 0.25. Hypanthium present; very short. The perianth comprising distinct calyx and corolla. Calyx 4; covering the rest of the flower in bud; not Swartzieae type; polysepalous; more or less regular; members imbricate. Corolla present; regular (the petals equal); 5; without greatly reduced members; polypetalous. Petals imbricate; imbricate-ascending. Disk absent. The androecium comprising 10 members; members all free of one another; comprising only fertile stamens. Fertile stamens 10. Anthers attached well above the base of the connective; dehiscing longitudinally. Ovary stipitate; somewhat eccentric, with the stipe adnate. Ovules few (2).
Fruit, seed and seedling. Fruit asymmetric, flattened, stipitate and apiculate. The mature valves with conspicuous, prominent, raised venation; conspicuous venation reticulate, not predominantly longitudinal. Seeds with a straight or slightly oblique radicle.
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). 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 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; conspicuously pitted; medium-thin. Stomata adaxially very rare. Abaxial: Abaxial stomata predominantly paracytic. Abaxial epidermis papillate interveinally; with papillae over-arching the stomata, or with the papillae not over-arching the stomata. Abaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; conspicuously pitted in optical section; staining normally with safranin; medium-thin.
Wood anatomy. Wood storied.
Species number and distribution. 1 species (L. leptanthum). Tropical Africa.
Miscellaneous. Illustrations: • L. leptanthum: Leonard, in Fl. du Congo Belge (1952). • L. leptanthum leaflet: abaxial epidermis.
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’.