The genera of Leguminosae-Caesalpinioideae & Swartzieae

L. Watson and M.J. Dallwitz

Lasiobema (Korth.) Miq.

~ Bauhinia sensu lato, Phanera.

Habit and leaf form. Climbers or scramblers; with tendrils; unarmed.

Phyllotaxy spiral. The leaves ostensibly simple, or two-lobed (entire, emarginate or bilobed); palmately veined. Stipules absent or early caducous or very inconspicuous in mature leaves; membranous.

Inflorescence and floral morphology. Bracts absent at anthesis. Bracteoles present; small, not enclosing the flower buds; absent at anthesis, or persistent beyond anthesis; not valvate.

The flowers hermaphrodite; not pentamerous throughout; departing from pentamery in the calyx, or in the calyx and in the androecium; coloured. Floral tube length relative to total hypanthium + calyx length about 0.8–1. Hypanthium present; turbinate. Calyx when splitting, 2–5; covering the rest of the flower in bud, or not covering the rest of the flower in bud; not Swartzieae type; gamosepalous; more or less regular, or markedly irregular (truncate, or divided only apically, or splitting irregularly); members not imbricate. Corolla present; very irregular; 5; without greatly reduced members; polypetalous. Petals clawed, or sessile (?); imbricate; imbricate-ascending; white, or yellow, or red. Disk present and conspicuous. The androecium comprising about 6 members (?); members all free of one another; members markedly unequal; including staminodia. The staminodia minute. Fertile stamens 3. 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 a two-valved pod (sometimes only tardily dehiscenct); straight, or curved; without markedly twisting or enrolling valves; becoming woody, or not becoming woody. The mature valves without prominent venation. Seeds endospermic, or non-endospermic; arillate (with a short funicular aril, the hilum crescentic); with a straight or slightly oblique radicle.

Transverse section of lamina. Leaves without 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 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 common; smooth. 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. Basally bent hairs absent. Adaxial: Adaxial interveinal epidermal cell walls straight in optical section; of medium thickness. Stomata adaxially very rare. Abaxial: Abaxial stomata predominantly paracytic. Abaxial epidermis not papillate. Abaxial interveinal epidermal cell walls straight, or gently undulating; staining normally with safranin; thin.

Pollen ultrastructure. Tectum reticulate; rugulose reticulate. Length of colpi greater than one half pole to pole distance.

Species number and distribution. About 12 species (? - including L.comosa, L. delavayi, L. dolichobotrys, L. harmsianum). Eastern Himalayas, Japan, Indochina, Java.

Tribe. Cercideae.

Miscellaneous. Illustrations: • L. scandens, 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.’.