Senegalia westiana (DC.) Britton & Rose

• Title

  Senegalia westiana (DC.) Britton & Rose

• Authors

  Nathaniel Lord Britton, Frances W. Horne

• Scientific Name

  Senegalia westiana (DC.) Britton & Rose

• Description

  Flora Borinqueña Senegalia Westiana Zarza Catch-and-keep Family Mimosaceae Mimosa Family Acacia Westiana De Candolle, Prodromus 2: 464. 1825. Senegalia Westiana Britton and Rose, North American Flora 2: 119. 1928. Previously confused by botanical authors with the South American Acacia riparia, this slender, prickly vine, or vine-like shrub, its membranous twice-compound leaves, with numerous, small, narrow leaflets, and usually numerous, clustered heads of small, white flowers, is frequent at lower and middle altitudes in Porto Rico, most plentiful in the dry, southern districts; it grows in thickets, on hillsides and river banks, climbing, or arching, forming delicately beautiful masses of foliage, as also on the islands Vieques and Culebra, ranging eastward through the Virgin Islands, and westward into Hispaniola. Senegalia a genus proposed by the naturalist Rafinesque in 1838, based upon the Acacia Senegal of tropical Africa as typical, includes, perhaps, as many as 80 species, or more, of tropical and warm-temperate regions. They are shrubs, vines and trees, with twice compound leaves, the leaf-stalks usually bearing a gland. Their small, regular flowers are densely clustered; the calyx mostly 5-toothed, or 5-lobed, the corolla mostly 5-lobed; the many, separate stamens have small anthers. The fruit is a thin, compressed or flat pod, which splits longitudinally into 2, papery or leathery valves, releasing the several or many seeds. Senegalia Westiana (commemorates Hans West, author of a treatise on the plants of St. Croix, the type locality of this species) is a woody vine, or clambering shrub, sometimes about 7 meters long, its branches armed with reflexed prickles. The leaves are from 7 to 15 centimeters long, the slender stalk bearing a concave gland; their primary divisions are from 4 to 12 pairs, each with from 15 to 25 pairs of thin, narrow, few-veined leaflets from 4 to 7 millimeters long and 1 or 1.5 millimeters wide. The several, or many, loosely clustered, short-stalked heads of white flowers are 8 or 10 millimeters in diameter. The pod is from 8 to 13 centimeters long, from 1 to 2 centimeters wide, densely velvety, papery in texture, short-stalked, its base narrowed.