| # The genera of Leguminosae-Caesalpinioideae and Swartzieae |

L. Watson and M.J. Dallwitz

### Librevillea Hoyle

Brachystegia klainei Harms

Type species: L. klainei (Pierre) Hoyle.

Habit and leaf form. Buttressed trees; unarmed.

Phyllotaxy spiral. The leaves compound; pinnate; imparipinnate to paripinnate (at least, with a rachis extension). The leaflets few per leaf; alternate (mostly), or opposite or sub-opposite and alternate; petiolulate; with markedly twisted petiolules; oblong-acuminate, symmetrical or nearly so (no more than slightly asymmetrical basally); pinnately nerved and reticulately veined, with a predominant ‘midrib’; without a continuous marginal nerve. Stipules present, persistent and conspicuous in mature leaves; subtruncate; intrapetiolar, connate. Stipels absent.

Inflorescence and floral morphology. The inflorescences axillary and terminal; branched; lax panicles. The flowers on slender pedicels, not distichous. Bracts very small. Bracteoles present; relatively large and enclosing the flower buds; persistent beyond anthesis; valvate.

The flowers 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. Hypanthium present; cupular. The perianth exclusively sepaline (but somewhat petaloid). Calyx present; small, 2; not covering the rest of the flower in bud. Corolla absent. Disk present and conspicuous. The androecium comprising 10 members (usually); with united members (basally connate); comprising only fertile stamens. Fertile stamens usually 10. Anthers attached well above the base of the connective; dehiscing longitudinally. Ovary shortly stipitate; free. Stigma very small on the filiform style. Ovules few (2(-3)).

Fruit, seed and seedling. Fruit a two-valved pod; valves twisting and enrolling during dehiscence; shortly stipitate, oblong, compressed, apiculate, becoming woody. The mature valves with conspicuous, prominent, raised venation; conspicuous venation 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. Adaxial: Adaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; conspicuously pitted; thick. 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; conspicuously pitted in optical section; scarcely staining with safranin; thin.

Species number and distribution. 1 species (L. klainei). Tropical Africa.

Tribe. Detarieae (Amherstieae of Cowan and Polhill 1981); Amherstieae clade of Bruneau et al. (2008).

Miscellaneous. Illustrations: • Librevillea klainei: Aubréville, Flore du Gabon (1968).

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: 4th August 2019. delta-intkey.com’.

Contents