The families of flowering plants.
AlternativelyCupuliferae A. Rich. (Is.str.), Cupulaceae Dulac
IncludingNothofagaceae Kuprianova, Quercineae (Quercaceae) Juss.Excluding Corylaceae
Habit and leaf form. Trees and shrubs; leptocaul. Mesophytic. Leaves evergreen, or deciduous; medium-sized; alternate; spiral, or distichous to four-ranked (rarely); ‘herbaceous’, or leathery; petiolate; non-sheathing; gland-dotted, or not gland-dotted; simple; epulvinate. Lamina dissected, or entire; when dissected, pinnatifid; pinnately veined; cross-venulate. Leaves stipulate. Stipules caducous. Lamina margins entire, or serrate, or dentate. Vegetative buds scaly. Leaves without a persistent basal meristem. Domatia occurring in the family (from 3 genera); manifested as hair tufts (consistently).
Leaf anatomy. Hydathodes present (occasionally), or absent. Mucilaginous epidermis present, or absent. Stomata mainly confined to one surface (abaxial); anomocytic.
Lamina without secretory cavities. Minor leaf veins without phloem transfer cells (Nothofagus,Quercus).
Stem anatomy. Secretory cavities absent. Cork cambium present; initially superficial. Nodes tri-lacunar. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. The secondary phloem stratified into hard (fibrous) and soft (parenchymatous) zones, or not stratified. ‘Included’ phloem absent. Xylem with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls scalariform, or scalariform and simple. Vessels without vestured pits. Wood partially storied (VR, Nothofagus), or not storied; parenchyma apotracheal (diffuse or in fine lines).
Reproductive type, pollination. Plants monoecious (nearly always), or dioecious (rarely). Gynoecium of male flowers pistillodial to absent. Pollination anemophilous (usually), or entomophilous (e.g. Castanea).
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; when solitary, axillary; when aggregated, in catkins (usually, at least the males), or in heads, or in glomerules. The ultimate inflorescence unit cymose. Inflorescences when flowers aggregated, axillary; with male flowers usually in more or less reduced dichasia aggregated into aments or distributed along a branching axis, the females in 1–7(–15)-flowered clusters at the bases of these or in separate few-flowered inflorescences; with involucral bracts. The involucres accrescent (and sometimes cupular, subtending the fruit or sometimes enclosing it). Flowers bracteate; minute. Free hypanthium absent.
Perianthsepaline, or vestigial; (4–)6(–7); free to joined; 1 whorled. Calyx (if the perianth is so interpreted) (4–)6(–7) (in the form of small scales); polysepalous, or gamosepalous; blunt-lobed; regular; in male flowers imbricate.
Androecium (4–)6–12(–40) (in male flowers). Androecial members free of the perianth; all equal; free of one another; 1 whorled (or more when numerous?). Androecium exclusively of fertile stamens. Stamens (4–)6–12(–40); isomerous with the perianth to diplostemonous to polystemonous; oppositisepalous, or alternisepalous and oppositisepalous. Anthers dehiscing via longitudinal slits. Pollen grains aperturate; 3 aperturate, or 4–7 aperturate; colpate, or colporate; 2-celled.
Gynoecium (2–)3 carpelled (usually), or 6(–12) carpelled. The pistil (2–)3 celled (usally), or 6(–12) celled. Gynoecium syncarpous; synovarious; inferior.Ovary (2–)3 locular (usually), or 6(–12) locular (but the septa falling short of the one-locular apex). The ‘odd’ carpel when G3 anterior. Styles(2–)3 (usually), or 6(–12) (as many as the locules); free; apical. Stigmas dry type; non-papillate; Group II type. Placentation axile, or apical. Ovules2 per locule; pendulous; non-arillate; anatropous; bitegmic (usually), or unitegmic (Nothofagus); crassinucellate. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; proliferating (sometimes), or not proliferating. Synergids sometimes with filiform apparatus. Endosperm formation nuclear. Embryogeny onagrad.
Fruit non-fleshy; indehiscent (subtended by the accrescent involucre, which sometimes encloses it before opening like a pericarp); a nut (with stony or leathery pericarp), or a samara (rarely); usually 1 seeded (by abortion). Seeds non-endospermic. Seeds with starch. Cotyledons 2. Embryo achlorophyllous (3/8).
Seedling.Germination phanerocotylar (e.g. Fagus), or cryptocotylar (e.g. Castanea).
Physiology, biochemistry. Not cyanogenic. Alkaloids present (very rarely), or absent. Iridoids not detected. Proanthocyanidins present (mostly), or absent; when present, cyanidin, or cyanidin and delphinidin. Flavonols present; quercetin, or kaempferol and quercetin, or kaempferol, quercetin, and myricetin. Ellagic acid present (mostly), or absent (4 genera listed). Arbutin absent. Aluminium accumulation demonstrated (perhaps, in Quercus spp.), or not found (mostly). Sugars transported as sucrose, or as oligosaccharides + sucrose, or as sugar alcohols + oligosaccharides + sucrose (but sucrose always predominating, in 29 species from 3 genera). C3. C3 physiology recorded directly in Quercus.
Geography, cytology. Frigid zone, temperate, and sub-tropical. Cosmopolitan, except tropical South America and tropical and South Africa. X = (11-)12(-13).
Taxonomy.Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Rosiflorae; Fagales. Cronquist’s Subclass Hamamelidae; Fagales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Fagales.
Species about 900. Genera 9; Fagus, Nothofagus, Lithocarpus, Castanopsis,Colombobalanus, Castanea, Chrysolepis, Quercus, Trigonobalanus.
Economic uses, etc. Important sources of hardwood timber (oak, beech, chestnut), chestnuts (Castanea), and (from Quercus) cork and tannins.