| # The genera of Leguminosae-Caesalpinioideae and Swartzieae |

L. Watson and M.J. Dallwitz

### Loesenera Harms

Ibadja A. Chev.

Type species: L. kalantha Harms.

Habit and leaf form. Small trees, or shrubs; unarmed.

Phyllotaxy spiral. The leaves compound; pinnate; paripinnate. The leaflets few per leaf (in 1–5 pairs); leathery, obliquely oblong or lanceolate, acuminate (not emarginate), opposite or sub-opposite; petiolulate; with markedly twisted petiolules; markedly asymmetrical; without a continuous marginal nerve. Stipules absent or early caducous or very inconspicuous in mature leaves (striate, deciduous); membranous. Stipels absent.

Inflorescence and floral morphology. The inflorescences terminal; unbranched; simple racemes. The flowers not distichous. Bracts ovate, velvety outside, soon deciduous, absent at anthesis. Bracteoles present (at the base of the calyx); not petaloid, similar in size and shape to the bracts and also velvety ouside, relatively large and enclosing the flower buds; persistent beyond anthesis; not valvate; free.

The flowers small; hermaphrodite; not pentamerous throughout; departing from pentamery in the calyx, or in the calyx and in the corolla. Floral tube length relative to total hypanthium + calyx length about 0.5. Hypanthium present; funnel-shaped. 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 (the segments broadly oval or ovate, velvety outside); members imbricate. Corolla present; very irregular (usually comprising three large, obovate petals resembling one another, and two tiny abaxials); (4–)5; including greatly reduced members; polypetalous. Petals shortly clawed (the large ones); imbricate; white, or red (or pink). 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; eccentric, with the stipe adnate. Stigma minute, capitellate. Ovules few.

Fruit, seed and seedling. Fruit a two-valved pod; valves twisting and enrolling during dehiscence; broadly oblong, compressed and often velutinous, becoming woody. The mature valves without prominent venation. Seeds not arillate; with a straight or slightly oblique radicle.

Transverse section of lamina. Druses absent from the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders 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. 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 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. Abaxial interveinal epidermal cell walls markedly sinuous in high-focus optical section; not conspicuously pitted in optical section; staining normally with safranin; thin.

Wood anatomy. Wood not storied. Intervascular pits very small.

Pollen ultrastructure. Tectum punctate; smooth punctate, or puncticulate. Length of colpi greater than one half pole to pole distance.

Species number and distribution. 4 species (L. gabonensis, L. kalantha, L. talbotii, L. walkeri). Tropical West Africa.

Tribe. Detarieae; Amherstieae clade of Bruneau et al. (2008).

Miscellaneous. Illustrations: • Loesenera gabonensis and L. walkeri: 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’.

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