The genera of Leguminosae-Caesalpinioideae & Swartzieae
Type species: S. letestui (Pellegr.) J. Léonard.
Habit and leaf form. Trees; unarmed.
The leaves compound; pinnate; paripinnate. The leaflets many per leaf; alternate; petiolulate; without noticeably twisted petiolules; elliptic-acuminate, pellucid-punctate, each with a marginal gland near the base; closely pinnately veined, with a predominant midrib (this gland-tipped); with a strong, continuous marginal nerve. Stipules absent or early caducous or very inconspicuous in mature leaves (caducous); membranous. Stipels absent.
Inflorescence and floral morphology. The inflorescences axillary (shorter than the leaves); unbranched; simple racemes. The flowers distichous. Bracts small, 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 and in the corolla. Hypanthium present (short). Calyx 4; covering the rest of the flower in bud; not Swartzieae type; polysepalous; more or less regular; members imbricate to not imbricate (subvalvate). Corolla present; very irregular; 1; with the one elliptic, glabrous, caducous petal, without greatly reduced members; monopetalous. Petals clawed. Disk absent. The androecium comprising 10 members; with united members (9 of the 10 being joined basally); members markedly unequal; comprising only fertile stamens. Fertile stamens 10 (all with similar anthers). Anthers attached well above the base of the connective; dehiscing longitudinally. Ovary stipitate; eccentric, with the stipe adnate. Ovules numerous.
Fruit, seed and seedling. Fruit 1–2 seeded, a two-valved pod (with elongate valves); much compressed, oblong-lanceolate acuminate, straight; without markedly twisting or enrolling valves; the valves thin, leathery, not becoming woody. The mature valves with conspicuous, prominent, raised venation; conspicuous venation not predominantly longitudinal. Seeds not arillate; with a straight or slightly oblique radicle. Cotyledons epigeal.
Transverse section of lamina. Mesophyll secretory cavities (gland-dots) common; epithelium-lined.
Wood anatomy. Wood without septate fibres; not storied; with normal intercellular canals; without traumatic canals.
Species number and distribution. 1 species (S. letestui). Tropical Africa.
Tribe. Detarieae; Detarieae sensu stricto clade of Bruneau et al. (2008).
Miscellaneous. Illustrations: • S. letestui: Aubréville, Flore du Gabon (1968). • S. letestui, 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’.