The Genera of Leguminosae-Caesalpinioideae and Swartzieae
= Bauhinia. Previously placed in Sophorieae or Cadieae.
Habit and leaf form. Trees; without tendrils; unarmed. Leaves simple (unifoliolate, petiolate, cordate-acuminate, entire). Venation palmate, parallel or fan-like (5–7-nerved). Stipules absent or early caducous or very inconspicuous (small, ovate, deciduous); neither leafy nor spinescent; not connate.
Inflorescence and floral morphology. Flowers hermaphrodite; pentamerous, or not pentamerous throughout; departing from pentamery in the corolla; coloured; in simple racemes, or in panicles. Inflorescences axillary (racemes), or terminal (panicles); of racemose units. Bracts persistent beyond anthesis (very small). Bracteoles absent; absent at anthesis. Hypanthium present. Calyx gamosepalous; not covering the rest of the flower in bud (open before anthesis); markedly zygomorphic (truncate or irregularly 5-dentate); 5 partite (obtuse); not imbricate; not Swartzieae type. Corolla present (the petals about twice as long as calyx); slightly zygomorphic (the petals nearly equal, the posterior broader); polypetalous; without any greatly reduced petals. Petals yellow; 5 (to 6 partite); imbricate; imbricate-ascending. Clawed petals present (all the petals long-clawed). Androecium of ten parts; members all free of one another; members all more or less equal in length (longer than the petals); without staminodia. Fertile stamens 10. Anthers attached well above base of connective (sagittate). Dehiscence longitudinal. Ovary stipitate; free. Stigma not peltate (minute). Ovules few.
Fruit, seed and seedling. Fruit a two-valved pod (flat, tardily dehiscent); not becoming woody (thin); with veins other than the longitudinal ones predominating; not winged; without markedly twisting or enrolling valves. Seeds endospermic; arillate (the hilum crescentic); with an inflexed radicle (embryo somewhat curved). Cotyledons flat; epigeal.
Wood anatomy. Wood storied; without normal intercellular canals; without traumatic canals.
Cytology, geography, etc. Basic chromosome number, x = 13. 2n = 26. 1 species. Australia. Widely cultivated.
The interactive key provides access to the character list, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, and summaries of attributes within groups of taxa.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1993 onwards. The genera of Leguminosae-Caesalpinioideae and Swartzieae: descriptions, identification, and information retrieval. In English and French; French translation by E. Chenin. Version: 22nd March 2009. http://delta-intkey.com’.