The Genera of Leguminosae-Caesalpinioideae and Swartzieae
The Genera of Leguminosae-Caesalpinioideae and Swartzieae |
|
Including Senna Mill., Chamaecrista Moench., Cathartocarpus Pers., Cowellocassia Britt., Desmodiocassia B. & R., Ditremexia Raf., Bactyrilobium Willd., Adipera Raf., Chamaefistula G. Don, Chamaesenna Raf., Cowellocassia Britt., Desmodiocassia B. & R., Ditremexia Raf., Earleocassia Britt., Echinocassia B. & R., Emelista Raf., Gaumerocassia Britt., Herpetica Raf., Isandrina Raf., Leonocassia B. & R., Palmerocassia Britt., Panisia Raf., Peiranisia Raf., Phragmocassia B. & R., Pseudocassia B. & R., Psilorhegma (Benth.) B. & R., Pterocassia B. & R., Sciacassia Britt., Sericeocassia Britt., Tharpia B. & R., Vogelocassia Britt., Xerocassia B. & R.
Habit and leaf form. Trees, or shrubs, or herbs; without tendrils; unarmed. Phyllotaxy distichous, or spiral. Leaves compound, or reduced to phyllodes, and/or the leaflets tiny and early-caducous; pinnate (often with petiolar glands); paripinnate. Leaflets many per leaf, or few per leaf; opposite or sub-opposite; petiolulate; with petiolules not noticeably twisted. Stipules absent or early caducous or very inconspicuous, or present, persistent and conspicuous; leafy, or neither leafy nor spinescent; not connate. Stipels absent.
Inflorescence and floral morphology. Flowers hermaphrodite; pentamerous, or not pentamerous throughout; departing from pentamery in the androecium; coloured; in simple racemes, or in panicles; not distichous. Inflorescences axillary, or terminal; of racemose units, or of solitary flowers (rare). Bracts absent at anthesis, or persistent beyond anthesis. Bracteoles present (in Cassia sensu stricto at or near base of pedicel, in Chamaecrista at or above middle of pedicel), or absent (Senna); absent at anthesis, or persistent beyond anthesis. Hypanthium absent. Length of floral tube relative to total hypanthium plus calyx length, about 0.25. Calyx gamosepalous, or polysepalous; covering the rest of the flower in bud; more or less regular, or markedly zygomorphic; 5 partite; imbricate. Corolla present; slightly zygomorphic, or very zygomorphic; polypetalous; without any greatly reduced petals. Petals white (rare), or yellow, or red (rare); 5 (petals spreading); imbricate; imbricate-ascending. Clawed petals present. Disk absent. Androecium of fewer than ten parts, or of ten parts; members all free of one another; members all more or less equal in length (rarely), or members markedly unequal (th long filaments of 3 abaxial stamens sigmoidally curved in Cassia sensu stricto only); with staminodia, or without staminodia. Fertile stamens 5–10. Anthers attached at base of connective. Dehiscence via pores or short slits. Ovary sessile or subsessile, or stipitate; free. Ovules numerous.
Fruit, seed and seedling. Fruit a follicle (in Senna p.p. only), or a two-valved pod (Senna p.p., Chamaecrista), or indehiscent (always so in Cassia sensu stricto); becoming distinctly woody, or not becoming woody; straight, or curved; with prominent, raised veins, or without prominent raised veins; with the prominent veins predominantly longitudinal, or with veins other than the longitudinal ones predominating; conspicuously winged (rare), or not winged; valves twisting and enrolling during dehiscence (Chamaecrista only), or without markedly twisting or enrolling valves (Senna p.p., Cassia sensu stricto). Seeds endospermic (compressed dorsiventrally in Cassia sensu stricto, laterally in Senna and Chamaecrista); not arillate (funicle filiform (Cassia sensu stricto, Senna), or dilated (Chamaecrista)); with a straight or slightly oblique radicle; amyloid-negative; with galactomannan. Cotyledons of Type 1, or Type 2, or Type 3; with a vascular system in one plane; epigeal.
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; 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 interveinal epidermal cell walls straight in optical section; conspicuously pitted; of medium thickness. Stomata adaxially very rare. 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; thin.
Wood anatomy. Wood with septate fibres, or without septate fibres; not storied; without normal intercellular canals; without traumatic canals. Intervascular pits medium to large.
Pollen ultrastructure. Tectum punctate, or reticulate; smooth punctate, or puncticulate, or rugulose punctate; rugulose reticulate. Length of colpi greater than one half pole to pole distance, or less than one half pole to pole distance (rare).
Cytology, geography, etc. Basic chromosome number, x = 14. 2n = 14 and 26 (in Chamaecrista), or 22, or 24, or 26, or 28. About 520 species. Tropical and warm temperate excluding Europe. Widely cultivated.
Tribe. Cassieae.
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’.