Stems solitary, erect, greater than 20 cm in diam., smooth, unarmed. Leaves: leaf bases unarmed, forming crownshaft, crownshaft prominent, green, smooth; petiole unarmed; blade pinnate; plication reduplicate; segments linear-lanceolate, in more than 1 plane. Inflorescences axillary below crown of leaves, paniculate, with 2 or 3 orders of branching; prophyll tubular; peduncular bract greatly exceeding prophyll, leathery, splitting longitudinally on abaxial side and circumscissilly at base; rachillae covered with copious caducous dendritic trichomes, becoming glabrous. Flowers unisexual, sessile, in triads of 1 pistillate flower flanked by 2 staminate flowers. Staminate flowers: sepals 3, imbricate, membranaceous; petals 3, valvate; stamens 6(--10, rarely); anthers dorsifixed, often twisting upon drying; pistillode minute, obscurely 3-cleft. Pistillate flowers globose to conic; sepals 3, imbricate; petals 3, basally connate, distally valvate; staminodes 6, basally connate, adnate to corolla basally; pistil 1; ovules 1; style indistinct; stigmas 3. Fruits drupes, fibrous; stigmatic scar basal; exocarp ripening from green to red to purplish black at maturity, thin, leathery; mesocarp fleshy, oily; endocarp hard. Seeds 1, nearly globose [obovoid], dorsiventrally compressed, abaxially attached to endocarp; endosperm homogeneous; embryo basal; eophyll undivided, linear-lanceolate. x n = 18.
Most species of Roystonea are widely known as royal palms. They are cultivated worldwide and are especially favored as avenue trees. Long rows of gray-white columnar trunks are unmatched for their magnificence and stateliness. In some parts of the Caribbean, especially Cuba, Roystonea is a significant resource for thatch (leafbases only), timber, livestock feed, palmito (palm cabbage or heart-of-palm), and edible oil (F. A. Reynoso 1976; C. Ruebens 1968; T. A. Zanoni 1991; S. Zona 1991, 1996).