Common name. Agapanthus. Family Alliaceae.
Sometimes included in Liliaceae.
Habit and leaf form. Large herbs (with annual leaves); laticiferous (mucilaginous), or non-laticiferous and without coloured juice. Perennial. Leaves basal. Plants with a basal concentration of leaves; rhizomatous (creeping on the surface or subterranean). Mesophytic, or xerophytic. Leaves alternate; distichous; sessile; sheathing. Leaf sheaths with free margins. Leaves without marked odour; simple; epulvinate. Leaf blades entire; flat; linear, or lanceolate, or ovate; linear to ovate (to narrowly lanceolate); parallel-veined (multinerved); without cross-venules; sheathing. Leaf blade margins entire. Leaf anatomy. Hairs absent. Extra-floral nectaries absent. Stem anatomy. Secondary thickening absent.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the gynoecium (from septal nectaries). Entomophilous.
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in umbels. The terminal inflorescence unit cymose. Inflorescences scapiflorous (scape simple, 50–100 cm, leafless, hollow); terminal; umbellate, usually representing one or more contracted, helicoid cymes; with involucral bracts (the umbel surrounded by (1–)2(to several) bracts); spatheate (with reference to the one to several spathal involucral bracts). Flowers pedicellate (pedicels 5–8 cm long, articulated or not at the apex); bracteate; ebracteolate; regular to somewhat irregular (the stamens to the abaxial side of the style); 3 merous; cyclic; pentacyclic. Perigone tube present. Perianth of ‘tepals’; 6; 2 -whorled (3+3); isomerous; joined; petaloid; similar in the two whorls; white, or purple to blue. Androecial members definite in number. Androecium 6. Androecial members adnate (to the base of the perigone); all equal; free of one another; 2 -whorled (3+3). Androecium exclusively of fertile stamens. Stamens 6; all more or less similar in shape; isomerous with the perianth; alterniperianthial; filantherous (the filaments flat). Filaments appendiculate, or not appendiculate. Anthers dorsifixed; dehiscing via longitudinal slits; introrse. Gynoecium 3 carpelled. The pistil 3 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; superior. Ovary plurilocular; 3 locular; sessile. Gynoecium stylate. Styles 1; apical. Stigmas 1; capitate. Placentation axile. Ovules 20–50 per locule (numerous); campylotropous (usually), or anatropous.
Fruit and seed features. Fruit non-fleshy; dehiscent; a capsule. Capsules loculicidal. Fruit 20–100 seeded (many). Seeds endospermic. Endosperm oily. Cotyledons 1. Embryo straight to curved. Testa encrusted with phytomelan.
Etymology. From the Greek for "love" and "flower".