Giant, tufted, rosulate perennials, the older plants forming dense clumps with a short vertical subterranean stem. Leaves bifacial, basal, spirally arranged, linear to narrow-lanceolate, with massive starch-filled bases forming a bulb; margin of sheath thin, filmy, completely encircling the axis; leaf tip a cylindrical, obtuse, brown prolongation the surface of which is ultimately shed leaving a tuft of threadlike fibres. Inflorescence a sparse or densely contracted thyrse attaining a height of 5.5 m and terminating an axis which towards its base bears abundant leaves similar to, but much smaller than, those of the rosette. Large, often bright red bracts subtending the inflorescence branches and flowers. Flowers large, epigynous, with short pedicels each of which bears a prophyll. Tepals 6, petaloid, 5-nerved, nearly equal and up to 18 cm in length, fused at the base to form a nectar cup; the free portions spreading, eventually caducous; inner 3 tepals slightly dilated at base. Stamens 3 + 3, epitepalous, with linear or basally dilated erect filaments extending beyond the tepals; anthers to 3 cm long, tetrasporangiate, peltate with the apex of the filament enclosed in a tube formed by the connective, extrorse, bilocular, dehishing longitudinally by slits. Gynoecium syncarpous, 3-carpellate, 3-locular; septal nectaries well developed, opening around the base of the style; style simple, slender, with an obtuse, triangular stigma; ovules numerous, borne on axile placentas in 2 rows per locule. Fruit a loculicidal capsule. Seeds numerous and variable in size but usually provided with a lateral wing. Testa yellow to red-brown due to the presence of the breakdown products of phlobaphene (Huber 1969); endosperm composed of thin-walled cells rich in fats and aleurone. Embryo straight, with a broad obtriangular cotyledon.
KeywordsMegaspore Mother Cell Short Pedicel Lateral Wing Inflorescence Branch Dense Clump
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