The families of flowering plants.
IncludingNandinaceae Horan. (non J.G. Agardh)Excluding Nandinaceae, Leonticaceae,Podophyllaceae
Habit and leaf form. Shrubs (mostly, usually with distinct ‘long-’ and ‘short-’ shoots, the tissues commonly coloured yellow with berberine), or herbs (more or less, Epimedium). Mesophytic, or xerophytic. Commonly heterophyllous (the long-shoot leaves often spiny or transformed into spines), or not heterophyllous. Leaves evergreen, or deciduous; small to large; alternate; spiral; flat; ‘herbaceous’, or leathery, or modified into spines (especially on the long-shoots, the spines simple or branched); petiolate; non-sheathing; not gland-dotted; simple, or compound, or simple and compound; when compound, unifoliolate (the ‘simple’ form of Berberis perhaps representing this), or ternate, or pinnate. Lamina when simple, dissected, or entire; commonly spinose;pinnately veined; cross-venulate. Leaves stipulate (the stipules minute or vestigial), or exstipulate. Stipules when present, intrapetiolar; caducous. Lamina margins entire, or dentate (usually prickly). Leaves without a persistent basal meristem.
Leaf anatomy. Stomata mainly confined to one surface (abaxial); anomocytic.
Minor leaf veins without phloem transfer cells (Berberis, Epimedium, Mahonia).
Stem anatomy. Cork cambium present; initially deep-seated, or superficial. Nodes tri-lacunar, or multilacunar. Secondary thickening absent (?), or developing from a conventional cambial ring. Xylem with libriform fibres; with vessels. Vessel end-walls scalariform, or simple. Wood partially storied (VPI); parenchyma absent. Sieve-tube plastids S-type.
Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the perianth, or from the androecium (from the ‘honey-leaves’ of the perianth, which are interpretable as staminodial). Pollination entomophilous; mechanism conspicuously specialized (the stamens springing violently upwards when their irritable bases are touched).
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes, or in racemes, or in fascicles. The ultimate inflorescence unit cymose, or racemose. Inflorescences racemes, fascicles and cymes. Flowers small, or medium-sized; regular; (2–)3(–4) merous; cyclic; polycyclic (usually of 6–7(-9) cycles). Floral receptacle not markedly hollowed (short). Free hypanthium absent. Hypogynous disk absent.
Perianthwith distinct calyx and corolla; (8–)12(–15); free; 4–6(–7) whorled; isomerous. Calyx usually interpreted as (4–)6; 2 whorled (alternatively interpretable as bracts); polysepalous; regular; not persistent; imbricate. Corolla 6–12; 2–4 whorled (the outer two without nectaries, sometimes interpreted as petaloid K, the inner two or three whorls when present nectariferous, alternatively interpretable as staminodes); polypetalous; imbricate; regular; yellow, or orange.
Androecium 6. Androecial members free of the perianth; free of one another; 2 whorled (3+3). Androecium exclusively of fertile stamens, or including staminodes (if the inner petals are so interpreted). Staminodes if interpreted as such, 3–9; external to the fertile stamens. Stamens usually 6 (usually the same number as the nectariferous C); alternisepalous (i.e. usually oppositipetalous); opposite the corolla members. Anthers adnate; non-versatile; dehiscing by longitudinal valves; extrorse (the two valves posterior, but usually moving upwards and turning around, orientating the adhering pollen towards the centre of the flower); tetrasporangiate. Endothecium developing fibrous thickenings. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral. Anther wall initially with more than one middle layer. Tapetum glandular. Pollen without viscin strands. Pollen grains aperturate; 3 aperturate; spiraperturate; 2-celled.
Gynoecium ostensibly 1 carpelled (fancifully interpretable as 3). Carpels reduced in number relative to the perianth. The pistil 1 celled. Gynoeciummonomerous (with no convincing evidence of pseudomonomery?); ostensibly of one carpel; superior. Carpel shortly stylate; apically stigmatic; 1–6 ovuled. Placentation marginal to basal. Stigmas wet type, or dry type; papillate, or non-papillate; Group II type, Group III type, and Group IV type. Ovules ascending; arillate, or non-arillate; hemianatropous, or anatropous; bitegmic; crassinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; large. Synergids pear-shaped. Endosperm formation nuclear. Embryogeny onagrad.
Fruitfleshy. The fruiting carpel indehiscent; baccate. Seeds endospermic. Endosperm oily. Cotyledons flat. Embryo achlorophyllous (2/8); straight.
Seedling.Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Not cyanogenic (with the segregate families excluded). Alkaloids present (usually), or absent. Berberine present (?always, colouring the tissues yellow). Iridoids not detected. Proanthocyanidins present, or absent; when present, cyanidin, or delphinidin. Flavonols present, or absent; when present, quercetin, or kaempferol and quercetin, or quercetin and myricetin. Ellagic acid absent (6 species, 3 genera). Arbutin absent. Aluminium accumulation not found. Sugars transported as sugar alcohols + oligosaccharides + sucrose (Mahonia). C3. C3 physiology recorded directly in Berberis, Mahonia.
Geography, cytology. Temperate to sub-tropical. Widespread in the North Temperate, tropical mountains, South America.
Taxonomy.Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Ranunculiflorae; Ranunculales. Cronquist’s Subclass Magnoliidae; Ranunculales. APG 3 core angiosperms; peripheral eudicot; Superorder Ranunculanae; Order Ranunculales.
Species 575. Genera 4; Berberis, Epimedium, Mahonia, Vancouveria.
Economic uses, etc. Edible berries from Berberis spp. (barberry), Mahonia aquifolium (‘Oregon grape’).