The families of flowering plants
Including Illigeraceae Bl.Excluding Gyrocarpaceae
Habit and leaf form. Trees, or shrubs, or lianas; bearing essential oils. Self supporting, or climbing. Leaves alternate; aromatic; simple, or compound; peltate (often, in Hernandia), or not peltate; if compound, palmate. Lamina dissected, or entire; when dissected, palmatifid; palmately veined; cross-venulate. Leaves exstipulate.
Leaf anatomy. Stomata present; mostly paracytic.
Lamina with secretory cavities, or without secretory cavities. Secretory cavities containing oil, or containing mucilage. Cystoliths seemingly absent. The mesophyll with spherical etherial oil cells; containing mucilage cells, or not containing mucilage cells.
Stem anatomy. Cork cambium present; initially superficial. Nodes unilacunar. Primary vascular tissue in a cylinder, without separate bundles. Cortical bundles absent. Medullary bundles absent. 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 parenchyma paratracheal. Sieve-tube plastids P-type; type I (b).
Reproductive type, pollination. Plants hermaphrodite, or monoecious.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences; in cymes; regular; cyclic; tetracyclic.
Perianth with distinct calyx and corolla, or sepaline (?of tepals); 6–10 (35 in each whorl); free; more or less 2 whorled; isomerous; similar in the two whorls. Corolla not fleshy.
Androecium 3–5. Androecial members free of the perianth; free of one another; 1 whorled. Androecium exclusively of fertile stamens, or including staminodes (these in the form of 12 nectariferous glands outside the stamens, cf. Lauraceae). Staminodes external to the fertile stamens. Stamens 3–5; oppositisepalous (alternating with the inner perianth whorl). Anthers dehiscing by longitudinal valves. Anther wall of the dicot type. Pollen grains nonaperturate; 2-celled.
Gynoecium 1 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled. Gynoecium monomerous; of one carpel; inferior. Carpel stylate; apically stigmatic; 1 ovuled. Placentation apical. Ovules pendulous; anatropous; bitegmic; crassinucellate. Endosperm formation cellular.
Fruit non-fleshy. The fruiting carpel indehiscent; winged or enclosed in an inflated envelope derived from connate bracteoles. Fruit 1 seeded. Seeds non-endospermic. Cotyledons 2 (fleshy, oily, smooth or ruminate). Embryo straight.
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Not cyanogenic. Alkaloids present. Iridoids not detected. Arthroquinones detected (Illigera); polyacetate derived. Proanthocyanidins absent. Flavonols present; kaempferol and quercetin. Ellagic acid absent (Hernandia). Saponins/sapogenins absent. Aluminium accumulation not found. Sugars transported as sucrose (Hernandia).
Geography, cytology. Sub-tropical to tropical. Pantropical.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Magnoliiflorae; Laurales. Cronquists Subclass Magnoliidae; Laurales. APG 3 core angiosperms; Superorder Magnolianae; Order Laurales.
Species 54. Genera 3; Hazomalania, Hernandia, Illigera.
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’.