Habit and leaf form. Herbs. ‘Normal’ plants. Leaves well developed. Perennial; with neither basal nor terminal aggregations of leaves; rhizomatous and tuberous (some of the roots being modified to store water and nutrients). Self supporting, or climbing; when climbing, stem twiners. Mesophytic. Leaves medium-sized; alternate; spiral; flat; petiolate; non-sheathing; simple. Lamina generally inverted; entire; linear to lanceolate; parallel-veined; without cross-venules; attenuate at the base. Lamina margins entire.
Leaf anatomy. Stomata present; anomocytic. Guard-cells not ‘grass type’.
Lamina dorsiventral. The mesophyll containing calcium oxalate crystals. The mesophyll crystals raphides (abundant). Minor leaf veins without phloem transfer cells (Alstroemeria). Vessels absent.
Stem anatomy. Cork cambium absent. Secondary thickening absent. Xylem with vessels. Vessel end-walls horizontal; scalariform. Sieve-tube plastids P-type; type II.
Root anatomy. Roots without velamen. Root xylem with vessels; vessel end-walls scalariform, or scalariform and simple (mainly scalariform).
Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the perianth (from the bases of two or all of the inner tepals).
Inflorescence, floral, fruit and seed morphology. Flowers solitary (rarely), or aggregated in ‘inflorescences’; in cymes, or in umbels. The ultimate inflorescence unit cymose. Inflorescences terminal; umbelliform, helicoid cymes. Flowers bracteate (the bracts leaflike); medium-sized; regular to somewhat irregular; sometimes slightly zygomorphic; 3 merous; cyclic; pentacyclic. Perigone tube present, or absent.
Perianth with distinct calyx and corolla, or of ‘tepals’; 6; mostly free; 2 whorled (3+3); isomerous; petaloid, or sepaloid and petaloid; spotted; similar in the two whorls to different in the two whorls (the outer whorl often shorter, of different colour and less variegated); green, or orange, or red, or pink; deciduous.
Androecium 6. Androecial members free of the perianth; free of one another; 2 whorled (3+3). Androecium exclusively of fertile stamens. Stamens 6; diplostemonous; alterniperianthial. Anthers (pseudo-) basifixed, or dorsifixed; non-versatile; dehiscing via longitudinal slits; introrse. The endothecial thickenings spiral. Microsporogenesis successive. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; 1 aperturate; sulcate; 2-celled.
Gynoecium 3 carpelled. Carpels isomerous with the perianth. The pistil 1 celled, or 3 celled. Gynoecium syncarpous; synstylovarious; inferior. Ovary 1 locular, or 3 locular. Styles 1; apical. Stigmas 3; wet type. Placentation when unilocular, parietal; when trilocular, axile. Ovules in the single cavity 20–100 (‘many’); 20–100 per locule (‘many’); non-arillate; anatropous; bitegmic; tenuinucellate. Outer integument not contributing to the micropyle. Endothelium differentiated. Embryo-sac development Polygonum-type. Synergids beaked. Endosperm formation nuclear.
Fruit fleshy (sometimes), or non-fleshy; dehiscent (usually, occasionally explosively so), or indehiscent; a capsule (usually), or capsular-indehiscent, or a berry. Capsules when dehiscent, loculicidal. Fruit elastically dehiscent, or passively dehiscent. Seeds endospermic. Endosperm oily. Seeds without starch. Embryo well differentiated. Cotyledons 1 (not coleoptile-like). Embryo straight. Testa without phytomelan.
Seedling. Hypocotyl internode present (short). Seedling collar not conspicuous. Cotyledon hyperphyll elongated, or compact; assimilatory (when elongated), or non-assimilatory. Coleoptile absent. Seedling cataphylls present. First leaf dorsiventral. Primary root persistent.
Physiology, biochemistry. Not cyanogenic. Alkaloids absent. Proanthocyanidins absent. Flavonols present; kaempferol and quercetin. Ellagic acid absent. Saponins/sapogenins probably present.
Geography, cytology. Neotropical and Antarctic. Central and South America. X = 8, 9.
Taxonomy. Subclass Monocotyledonae. Superorder Liliiflorae; Liliales. APG (1998) Monocot; non-commelinoid. APG 3 (2009) Order: Liliales.
Species 200. Genera 4; Alstroemeria, Bomarea, Leontochir, Schickendantzia.
• Alstroemeria aurantiaca: Bot. Reg 1843, 1836.
• Alstroemeria ligtu: Bot. Reg. 1839, 13.
• Alstroemeria, Bomarea.