Alternatively Illicaceae
Excluding Phellinaceae, Sphenostemonaceae
Habit and leaf form. Small trees, or shrubs; leptocaul. Commonly heterophyllous (at least in Ilex aquifolium, which commonly exhibits unarmed leaves on mature shoots, cf. irreversible maturation in Hedera), or not heterophyllous. Leaves usually evergreen; alternate, or opposite (rarely), or whorled (rarely in `pseudowhorls'); usually spiral; leathery; petiolate; non-sheathing; simple. Lamina pinnately veined; cross-venulate. Leaves stipulate (stipules small), or exstipulate. Lamina margins entire (often prickly), or dentate. Domatia recorded (in one Ilex species); represented by pockets.
Leaf anatomy. Mucilaginous epidermis present, or absent. Stomata mainly confined to one surface (abaxial); anomocytic.
Minor leaf veins without phloem transfer cells (Ilex).
Stem anatomy. Cork cambium present; initially superficial. Nodes unilacunar, or tri-lacunar. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. `Included' phloem absent. Xylem with fibre tracheids; with vessels. Vessel end-walls oblique; scalariform. Vessels without vestured pits. Wood parenchyma apotracheal (diffuse).
Reproductive type, pollination. Dioecious, or polygamomonoecious. Female flowers with four staminodes, these sometimes petaloid.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in `inflorescences', or solitary (rarely); in cymes, in racemes, and in fascicles. The terminal inflorescence unit cymose, or racemose. Inflorescences cymes or fascicles, rarely racemes. Flowers regular; 4(-8) merous. Free hypanthium absent. Hypogynous disk absent.
Perianth with distinct calyx and corolla, or sepaline, or petaline, or vestigial; 0, or 4-5, or 8; 1 whorled, or 2 whorled; isomerous, or anisomerous. Calyx 4-5, or 8; 1 whorled; gamosepalous; imbricate. Corolla if present, 4-5, or 8; 1 whorled; gamopetalous (at the base), or polypetalous; imbricate, or valvate.
Androecium 4-5, or 8(-12). Androecial members free of the perianth to adnate (usually adnate to the corolla base); free of one another; 1-3 - whorled. Androecium exclusively of fertile stamens. Stamens 4, or 8(-12); isomerous with the perianth to triplostemonous; oppositisepalous. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Tapetum probably glandular. Pollen grains aperturate, or nonaperturate; when aperturate, 3(-4) - aperturate; colporate (colporoidate); 2-celled.
Gynoecium (2-)4-6(-24); syncarpous; eu-syncarpous; superior. Ovary (2-)4-6(-24) locular. Gynoecium non-stylate to stylate. Styles if detectable, 1. Stigmas wet type; non-papillate; Group IV type. Placentation apical. Ovules 1-2 per locule; pendulous; non-arillate (?); anatropous; unitegmic; crassinucellate (usually), or tenuinucellate (reported in two Ilex spp.). Endothelium differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; persistent. Synergids pear-shaped. Endosperm formation cellular. Embryogeny caryophyllad.
Fruit fleshy; indehiscent; a drupe (with as many pyrenes as locules). Seeds endospermic. Endosperm oily (and proteinaceous). Cotyledons 2. Embryo achlorophyllous (2/2); straight.
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Cyanogenic, or not cyanogenic. Alkaloids present, or absent (mostly). Iridoids absent. Proanthocyanidins absent. Flavonols present; kaempferol and quercetin. Ellagic acid absent (Ilex). Arbutin absent. Ursolic acid present. Saponins/sapogenins present, or absent. Aluminium accumulation not found. C3. C3 recorded in Ilex.
Geography, cytology. Temperate, sub-tropical, and tropical. Widespread. X = 9, 10.
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren's Superorder Corniflorae; Cornales. Cronquist's Subclass Rosidae; Celastrales. Takhtajan's Subclass Rosidae; Celastranae; Celastrales. Species 400. Genera 2; Ilex, Nemopanthus.
Economic uses, etc. Ilex species supply hard, white, fine-grained wood, used for inlay work and sometimes stained black as ebony substitute; Maté or Paraguay tea from dried leaves of I. paraguensis; many species and hybrids used as ornamentals.
Illustrations. aquif339.gif aquif597.gif
