| # The genera of Leguminosae-Caesalpinioideae and Swartzieae |

L. Watson and M.J. Dallwitz

### Koompassia Maingay ex Benth.

Abauria Recc.

Type species: K. malaccensis Maing.

Habit and leaf form. Trees; unarmed.

Phyllotaxy distichous, or spiral. The leaves compound; pinnate; imparipinnate. The leaflets few per leaf; alternate; petiolulate; without noticeably twisted petiolules; symmetrical or nearly so; pinnately veined, with a predominant ‘midrib’. Stipules absent or early caducous or very inconspicuous in mature leaves; membranous. Stipels absent.

Inflorescence and floral morphology. The inflorescences axillary, or terminal; branched; of cymose units (cymules); panicles. The flowers not distichous. Bracts absent at anthesis. Bracteoles present; small, not enclosing the flower buds; absent at anthesis, or persistent beyond anthesis.

The flowers small; hermaphrodite; pentamerous; white or green. Hypanthium absent, the androecium hypogynous. The perianth comprising distinct calyx and corolla. Calyx 5; covering the rest of the flower in bud; not Swartzieae type; polysepalous; more or less regular (the sepals rather thick); members imbricate, or not imbricate (then valvate). Corolla present; regular to slightly irregular (the petals subequal); exceeding the calyx, 5; without greatly reduced members; polypetalous. Petals sessile; imbricate; imbricate-ascending; white. Disk absent. The androecium comprising 5 members; members all free of one another; members all more or less equal in length; comprising only fertile stamens. Fertile stamens 5. Anthers up to twice as long as filaments, attached at the base of the connective; dehiscing via pores or short slits, or longitudinally. Ovary sessile or subsessile; free. Stigma not dilated (the style subulate). Ovules solitary.

Fruit, seed and seedling. Fruit oblong, compressed, indehiscent; not drupaceous; broadly papery-winged all round. Seeds non-endospermic; with a straight or slightly oblique radicle; amyloid-negative. Cotyledons of Type 2; epigeal.

Transverse section of lamina. Leaves without conspicuous phloem transfer cells in the minor veins. Druses common in the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis present, or 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; scabrid, or smooth. No compound or branched eglandular hairs seen. Capitate glands not seen. Hooked hairs present, or not seen. Cassieae-type leaf pseudo-glands not seen. Expanded and embedded hair-feet absent. Basally bent hairs present. Adaxial: Adaxial interveinal epidermal cell walls straight in optical section; not conspicuously pitted; thick. Stomata adaxially very rare. Abaxial: Abaxial stomata predominantly paracytic. Abaxial epidermis papillate interveinally, or not papillate; with the papillae not over-arching the stomata. Abaxial interveinal epidermal cell walls straight, or gently undulating; not conspicuously pitted in optical section; scarcely staining with safranin; medium-thin.

Wood anatomy. Wood without septate fibres; storied; without normal intercellular canals; without traumatic canals. Intervascular pits medium to large.

Pollen ultrastructure. Tectum striate; interwoven striate. Length of colpi greater than one half pole to pole distance.

Species number and distribution. 3 species (K. excelsa, K. grandiflora and K. malaccensis). Malay peninsula to Borneo, New Guinea.

Tribe. Cassieae.

Miscellaneous. Illustrations: • Koompassia grandiflora: Ding Hou, Fl. Malesiana 12 (1995). • Koompassia malaccensis, 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: 4th August 2019. delta-intkey.com’.

Contents