Mentzelia aspera L.

• Title

  Mentzelia aspera L.

• Authors

  Nathaniel Lord Britton, Frances W. Horne

• Scientific Name

  Mentzelia aspera L.

• Description

  Flora Borinqueña Mentzelia aspera Pegadora Rough Mentzelia Family Loasaceae Loasa Family Mentzelia aspera Linnaeus, Species Plantarum 516. 1753. Of interest as the only representation of the Loasa Family found in Porto Rico, this very rough, slender, straggling or half-climbing, herbaceous plant is occasional in the dry, southern and southwestern districts, and not known to us elsewhere on the island, except as once reported from the vicinity of Rincon on the western coast. The rough-hairy stems, leaves and fruits make it unpleasant to handle,and they may become attached to clothing, or to animals, and thus transported and scattered, but the yellow flowers are quite conspicuous and attractive. In the West Indies it grows also in Santo Domingo, Haiti, Cuba, Jamaica and Saint Vincent; it ranges widely through continental tropical America, from Mexico to Ecuador and Venezuela, and occurs on the small Dutch islands off the coast of Venezuela. Mentzelia, a Linnaean genus, named in honor of Christian Mentzel, a German botanist who lived from 1622 to 1701, includes some 35 herbaceous species,all American; they have alternate leaves, and the regular and perfect flowers are solitary or clustered at the ends of branches. The cylindric or club-shaped tube of the calyx sheaths the ovary, and is usually 5-lobed at the top; there are 5, spreading petals and many stamens with slender filaments; the 1-celled ovary contains many ovules. The fruit is a capsule, opening at the top, containing angled, rough or striated seeds. Mentzelia aspera (rough) is usually much-branched, from 1 to 2 meters long. Its leaves are various in form, lance-shaped, halberd-shaped or nearly triangular, slender-stalked, thin, pointed, from 3 to 8 centimeters long, their margins toothed, or incised; the few, or usually solitary, stalkless flowers are light yellow, 1.5 to 2 centimeters broad; the calyx-lobes are narrow, long-pointed, about 8 millimeters long, somewhat shorter than the oval petals; there are about 20 stamens, much shorter than the petals. The capsule is narrowly club-shaped, rough-hairy, 2 or 3 centimeters long. Our illustration was first published in "Addisonia", plate 504. September, 1930.