The Families of Flowering Plants
The Families of Flowering Plants | |
Excluding Tetramelaceae
Habit and leaf form. Tall, glabrous herbs (with the habit of Cannabis). ‘Normal’ plants. Plants non-succulent. Perennial. Leaves alternate; petiolate; non-sheathing; compound; pinnate. Lamina pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins dentate. Domatia occurring in the family; manifested as pockets.
Leaf anatomy. Stomata present; anomocytic.
Lamina dorsiventral. The mesophyll with sclerencymatous idioblasts (H-shaped, in Octomeles), or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells.
Stem anatomy. Cork cambium present; initially superficial. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. ‘Included’ phloem absent. Xylem with libriform fibres. Vessel end-walls simple. Vessels without vestured pits. Wood not storied; parenchyma paratracheal.
Reproductive type, pollination. Unisexual flowers present. Plants dioecious, or androdioecious, or polygamomonoecious. Gynoecium of male flowers absent. Pollination anemophilous.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in fascicles. Inflorescences crowded fascicles on long, leafy branches.
Perianth sepaline; 3–9. Calyx 3–9 (male flowers), or 3–8 (female and hermaphrodite flowers); polysepalous; members unequal; persistent.
Androecium 3–5 (in hermaphrodite flowers), or 8–25 (in male flowers). Androecial members free of the perianth; free of one another. Androecium exclusively of fertile stamens (or hermaphrodite flowers sometimes with some imperfect stamens?). Stamens 8–25 (male flowers), or 3–5 (hermaphrodite flowers); filantherous (the filaments short). Anthers dorsifixed; dehiscing via longitudinal slits; extrorse; tetrasporangiate. Pollen grains aperturate; 3 aperturate; colporate; 2-celled.
Gynoecium 3–5 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious (open at the apex); inferior (ribbed). Ovary 1 locular. Epigynous disk absent. Gynoecium stylate. Styles 3–5 (each deeply bifid). Stigmas dry type; papillate; Group II type. Placentation parietal. Ovules in the single cavity 30–100 (‘many’); anatropous; bitegmic; tenuinucellate. Outer integument contributing to the micropyle. Embryo-sac development Allium-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; persistent. Synergids pear-shaped. Endosperm formation nuclear. Embryogeny onagrad.
Fruit non-fleshy; dehiscent; a capsule (membranous). Capsules opening apically between the persistent styles. Fruit 30–100 seeded (‘many seeded’). Seeds more or less non-endospermic. Embryo well differentiated (but small). Cotyledons 2 (oily). Embryo straight. Testa coarsely reticulate.
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Not cyanogenic. Proanthocyanidins absent. Flavonols present; kaempferol and quercetin. Ellagic acid absent. Aluminium accumulation not found.
Geography, cytology. Holarctic. Temperate to tropical. Dry Western Eurasia, dry North America. N = 11.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Violiflorae; Violales. Cronquist’s Subclass Dilleniidae; Violales. APG (1998) Eudicot; core Eudicot; Rosid; Eurosid I; Cucurbitales. Species 2. Genera 1; only genus, Datisca.
Illustrations. • Technical details (Datisca).
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 specified attributes, summaries of attributes within groups of taxa, geographical distribution, genera included in each family, classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG), and notes on the APG classification.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 10th April 2008. http://delta-intkey.com’.
