The Genera of Leguminosae-Caesalpinioideae and Swartzieae
| The Genera of Leguminosae-Caesalpinioideae and Swartzieae | |
Habit and leaf form. Trees, or shrubs; without tendrils; unarmed. Crowded on the new growth. Phyllotaxy spiral. Leaves compound (large); bipinnate (with numerous pinnae, and ending in a pair of them); with rachides adaxially ridged. Leaflets many per leaf. Never having bipinnate leaves with short, spine-tipped rachides and flattened pinnae. Stipules absent or early caducous or very inconspicuous (minute); neither leafy nor spinescent. Stipels absent.
Inflorescence and floral morphology. Flowers hermaphrodite; pentamerous; coloured; in simple racemes (slender, many flowered); not distichous. Inflorescences axillary and terminal; of racemose units. Bracteoles absent at anthesis. Hypanthium present. Length of floral tube relative to total hypanthium plus calyx length, about 0.25. Calyx polysepalous; covering the rest of the flower in bud; 5 partite; not imbricate. Corolla present; actinomorphic to slightly zygomorphic; polypetalous; without any greatly reduced petals. Petals yellow; 5. Androecium of ten parts; members all free of one another; without staminodia. Fertile stamens 10. Dehiscence introrse. Ovary white-tomentose.
Fruit, seed and seedling. Fruit a two-valved pod; conspicuously winged (with two wings). Seeds 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. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders absent. Laminae dorsiventral. Mesophyll without unaligned fibres or sclereids. Minor veins lacking accompanying fibrous tissue.
Leaf lamina epidermes. Epidermal crystals not seen either adaxially or abaxially. Simple unbranched hairs common. 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 interveinal epidermal cell walls straight in optical section; of medium thickness. Stomata adaxially very rare. Abaxial stomata predominantly paracytic. Abaxial epidermis not papillate. Abaxial interveinal epidermal cell walls straight, or gently undulating; scarcely staining with safranin; thin.
Wood anatomy. Wood not storied.
Cytology, geography, etc. 3 species. North America. Mexico. Not widely cultivated.
Tribe. Caesalpinieae.
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: 19th October 2005. http://delta-intkey.com’.