Monographs Details: Poinsettia cyathophora (Murray) Klotzsch & Garcke
Authority: Britton, Nathaniel L. Flora Borinqueña.
Description:Species Description - This herbaceous plant, frequent in waste and cultivated grounds in Porto Rico, occurring also on Mona and Vieques, is often characterized by curiously fiddle-shaped leaves, but they are sometimes unlobed and merely toothed; the upper leaves usually have a white, pink, or scarlet blotch on the upper side near the base; the small, greenish, clustered, terminal flowers are inconspicuous. The species is distributed nearly all over the West Indies, except the Bahama Islands, widely in continental tropical America, and ranges northward into Florida; it is occasionally planted for ornament, and has sometimes been classified as a variety or race of Poinsettia heterophylla.
Poinsettia commemorates Joel Roberts Poinsette, of South Carolina. The genus was established by R. Graham, in 1836, based upon the Mexican shrub Poinsettia pulcherrima, the Flor de pascua, commonly grown for ornament in tropical gardens. Some 12 species are known, mostly American in distribution. They are herbaceous plants, or shrubs, with the lower leaves alternate, the upper ones mainly opposite and variously blotched, or colored. The small, incomplete flowers are in terminal, bracted clusters, each subtended by a fimbriate involucre bearing concave, or cup-shaped glands; there is neither a calyx nor a corolla; the ovary is 3-celled, and there are 3 styles. The fruit is a small capsule with 3 rounded lobes.
Poinsettia cyathophora (referring to the cup-shaped glands of the involucres) is an annual or perennial, stout, somewhat hairy or smooth herb from 0.3 to 0.8 meter high. The variously shaped and blotched leaves are about 8 centimeters long, or shorter. The capsule is 6 or 8 millimeters in diameter.
There are 2 other wild Poinsettias in the Porto Rico Flora.
Euphorbia cyathophora Murray, Commentationes Societatis Regias Scientiarum Goettingensis 7: 81. 1786.
Poinsettia cyathophora Klotsch and Garcke, Monatschrifte der Akademie der Wissenchaften zie Berlin 1859: 253. 1859.