Erythroxylaceae Kunth

Scientific Description

Common name. Coca Family.

Family Sometimes included in Linaceae.

Habit and leaf form. Trees and shrubs. Leaves well developed (sometimes accompanied by scale leaves). Mesophytic. Leaves alternate, or opposite (rarely); usually spiral; ‘herbaceous’, or ‘herbaceous’ and membranous (the branches often covered with rudimentary leaves in the form of distichous scales); petiolate; non-sheathing; simple. Leaf blades entire; often persistently twice folded (longitudinally); pinnately veined. Leaves with stipules. Stipules interpetiolar (rarely), or intrapetiolar; often caducous. Leaf blade margins entire. Leaves without a persistent basal meristem. Stem anatomy. Nodes unilacunar. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite, or functionally male, or functionally female. Unisexual flowers present, or absent. Plants hermaphrodite, or dioecious (rarely). Plants usually heterostylous.

Inflorescence and flower features. Flowers solitary (axillary), or aggregated in ‘inflorescences’; in fascicles. Inflorescences axillary. Flowers small; regular; 5 merous; cyclic; pentacyclic. Free hypanthium absent. Hypogynous disk absent. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx 5; 1 -whorled; polysepalous, or gamosepalous; imbricate (quincuncial), or valvate; regular; persistent. Corolla 5; 1 -whorled; appendiculate (the petals usually internally ligulate), or not appendiculate; polypetalous, or partially gamopetalous; imbricate, or contorted; regular. Fertile stamens present, or absent (female flowers). Androecium 10. Androecial members free of the perianth; all equal; coherent (united into a tube at the base); 1 - adelphous; 2 -whorled. Androecium exclusively of fertile stamens. Stamens 10; diplostemonous; alternisepalous and oppositisepalous. Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Fertile gynoecium present, or absent (male flowers). Gynoecium 3 carpelled. The pistil (2–)3 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; synovarious to synstylovarious; superior. Ovary plurilocular; (2–)3 locular (usually only one fertile). Gynoecium stylate. Styles (2–)3; free to partially joined; apical. Stigmas dry type; papillate; Group II type. Placentation axile, or apical. Ovules 1 per locule; funicled; pendulous; epitropous; non-arillate; anatropous, or hemianatropous.

Fruit and seed features. Fruit fleshy; indehiscent; a drupe (one-loculed); 1 seeded. Seeds endospermic, or non-endospermic (rarely). Endosperm not oily (starchy). Seeds with starch. Cotyledons 2. Embryo chlorophyllous (1/1); straight. Seedling. Germination phanerocotylar.

Physiology, biochemistry. Aluminium accumulation not found.

Geography, cytology, number of species. World distribution: pantropical. X = 12. 250 species.

Economic uses, etc. Cocaine is extracted from the leaves of coca (Erythroxylum coca).