Aquifoliaceae Bercht. & J.Presl

Scientific Description

Common name. Holly Family.

Habit and leaf form. Small trees, or shrubs; usually evergreen; 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 alternate, or opposite (rarely), or whorled (rarely in ‘pseudowhorls’); usually spiral; leathery; petiolate; non-sheathing; simple. Leaf blades pinnately veined; cross-venulate. Leaves with stipules (stipules small), or without stipules. Leaf blade margins entire (often prickly), or dentate. Domatia recorded (in one Ilex species); represented by pockets. Stem anatomy. Nodes unilacunar, or tri-lacunar. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers functionally male, or functionally female, or hermaphrodite, functionally male, and functionally female. Unisexual flowers present. Plants dioecious, or polygamomonoecious. Female flowers with staminodes (four staminodes, these sometimes petaloid).

Inflorescence and flower features. 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. Fertile stamens present, or absent (female flowers). 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. Fertile gynoecium present, or absent (in males). Gynoecium (2–)4–6(–24) carpelled. The pistil (2–)4–6(–24) celled. Gynoecium syncarpous; eu-syncarpous; superior. Ovary plurilocular; (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; apotropous; non-arillate; anatropous.

Fruit and seed features. 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. Aluminium accumulation not found. Photosynthetic pathway: C₃.

Geography, cytology, number of species. World distribution: widespread. X = 9, 10. 400 species.

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.