The families of flowering plants
Habit and leaf form. Trees and shrubs; with coloured juice. Mesophytic, or xerophytic. Leaves alternate; petiolate; non-sheathing; gland-dotted, or not gland-dotted; aromatic, or without marked odour; simple. Lamina dissected; palmatifid; palmately veined; cross-venulate. Leaves stipulate. Lamina margins serrate. Leaves without a persistent basal meristem.
Leaf anatomy. Mucilaginous epidermis often present.
Minor leaf veins without phloem transfer cells (Cochlosperma).
Stem anatomy. Secretory cavities present (in the cortex and pith); with mucilage. Cortical bundles absent. Medullary bundles absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. The secondary phloem stratified into hard (fibrous) and soft (parenchymatous) zones. Included phloem absent. Xylem with fibre tracheids. Vessels without vestured pits (but with vestured fibre pits). Wood partially storied (VPI), or not storied; parenchyma predominantly apotracheal.
Reproductive type, pollination. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences; in panicles and in racemes. Inflorescences paniculate or racemose. Flowers large; regular to somewhat irregular. Free hypanthium absent.
Perianth with distinct calyx and corolla; 8, or 10; 2 whorled; isomerous. Calyx 4, or 5; 1 whorled; polysepalous; not persistent (deciduous); imbricate. Corolla 4, or 5; 1 whorled; polypetalous; imbricate, or contorted; yellow.
Androecium 15–100 (many). Androecial members branched (with trunk bundles); maturing centrifugally; free of the perianth; all equal to markedly unequal; free of one another. Androecium exclusively of fertile stamens. Stamens 15–60; polystemonous. Anthers dehiscing via pores (these apical, often confluent). Pollen grains aperturate; 3 aperturate; colporate; 2-celled.
Gynoecium 3–5 carpelled. The pistil 1 celled, or 3 celled. Gynoecium syncarpous; eu-syncarpous; superior. Ovary 1 locular, or 3 locular. Styles 1; attenuate from the ovary; apical. Stigmas 1 (minute). Placentation when unilocular, parietal; when trilocular, axile. Ovules in the single cavity when unilocular, 20–100 (i.e. many); when trilocular, 20–50 per locule (i.e. many); anatropous; bitegmic; crassinucellate. Outer integument contributing to the micropyle. Endosperm formation nuclear.
Fruit non-fleshy; dehiscent; a capsule. Capsules three to five valvular. Seeds endospermic. Endosperm oily. Cotyledons 2. Embryo straight, or curved, or coiled. Micropyle zigzag.
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Proanthocyanidins present; cyanidin. Flavonols present; kaempferol, quercetin, and myricetin. Ellagic acid present (Cochlospermum). Saponins/sapogenins present. Aluminium accumulation not found.
Geography, cytology. Tropical. Widespread-tropical, except Malaysia.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Malviflorae; Malvales. Cronquists Subclass Dilleniidae; Violales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Malvales (as a synonym of Bixaceae?).
Species 20–25. Genera 2; Amoreuxia, Cochlospermum.
This description is offered for casual browsing only. We strongly advise against extracting comparative information from it. This is much more easily achieved using 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, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG).
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 19th December 2012. http://delta-intkey.com’.