Monographs Details: Operculina tuberosa (L.) Meisn.
Authority: Britton, Nathaniel L. Flora Borinqueña.
Description:Species Description - Elegant when in bloom, by large, bright yellow flowers among deeply divided leaves, this vine is occasionally planted for ornament in Porto Rico, and may, sometimes, be spontaneous by seed, as it is on other West Indian Islands, and in Florida, being distributed through Santo Domingo, Cuba, Jamaica, the Virgin Islands and in Guadeloupe; it has wide range in continental tropical America, and grows also in tropical parts of the Old World.
Operculina (Latin, referring to the characteristic lid, or operculum, of the fruit) is a tropical genus of about 15 species, established by the botanist Manso in 1836, in a volume upon plants of Brazil. They are perennial vines, with alternate leaves, and large, clustered, or solitary, axillary flowers. The 5, broad sepals become enlarged in fruit; the corolla is funnelform or bell-shaped; the 5 stamens have large anthers; the ovary is 2-celled, and there are 8, round stigmas. The fruit is a capsule, which opens by a lid, releasing the large, smooth, black seeds.
Operculina tuberosa is smooth,and may reach a length of several meters, the stem rather stout. Its long-stalked, deeply 5-lobed, or 7-lobed leaves are from 8 to 20 centimeters broad, their pointed lobes lance-shaped. The flowers, several together, or solitary, are borne on a stout stalk about as long as the leaf-stalk, or longer, the individual ones on upwardly thickened stalks from 1 to 4 centimeters long; the ovate, blunt sepals, at first 2 or 3 centimeters long, become 5 or 6 centimeters long in fruit; the showy yellow corolla is about 5 centimeters long, the limb 6 or 7 centimeters wide. The globose capsule, enclosed by the sepals, is about 3 centimeters in diameter.
Ipomoea tuberosa Linnaeus, Species Plantarum 160. 1753.
Operculina tuberosa Meissner, in Martius, Flora Brasiliensis 7: 212. 1869.