Melanthera nivea (L.) Small

• Title

  Melanthera nivea (L.) Small

• Author(s)

  Nathaniel Lord Britton, Frances W. Horne

• Scientific Name

  Melanthera nivea (L.) Small

• Description

  Flora Borinqueña Melanthera nivea Coastal Melanthera Family Carduaceae Thistle Family Bidens nivea Linnaeus, Species Plantarum 833. 1755 Melanthera nivea Small, Flora of the Southeastern United States 1251.1903. A smooth, broad -leaved, herbaceous plant, inhabiting coastal sands and thickets, found in northern and eastern Porto Rico, and on the small islands Cayo Muertos, Vieques and Culebra; its further distribution is in the Lesser Antilles from St. Bart's to Tobago. The stalked heads of white, tubular, small flowers are attractive. Melanthera ( black anthers) a genus established by the botanist Rohr in 1792, consists of about 10, closely inter-related perennial herbs, sometimes quite woody, natives of tropical and subtropical America. Their leaves are opposite, stalked and toothed or somewhat lobed, their small, tubular flowers in stalked heads. The involucre of the flower-head is depressed-hemispheric, its bracts overlapping; the receptacle is convex, or low-conic, and scaly; the corollas are nearly cylindric, and 5-toothed; the anthers are sometimes black, the 2 style-branches long. The 4-angled achenes bear a pappus of awns, which fall away. Melanthera nivea (snow-white) is various in habit, sometimes upright, sometimes reclining, occasionally vine-like and up to 3 meters long, usually smaller, the 4-angled branches sparingly hairy. The slender-stalked ovate to nearly orbicular, bluntly toothed pointed leaves are from 5 to 9 centimeters long, green on both sides, sparingly hairy beneath. The flower-heads are solitary, or 2 or 3 together, about 2 centimeters in diameter; the ovate involucre-bracts are about 5 millimeters long. The achenes bear awns 3 millimeters long, or shorter. There are 5 species of Melanthera described in the Porto Rico Flora; of these, Melanthera confusa is also illustrated in this work.