摘要：Salvinia, water spangles, is a genus of 10 species of free-floating heterosporous aquatic ferns with two species introduced to North America. S. minima Baker was introduced into the eastern United States by at least 1814 and occurs mainly across the southeastern United States. S. molesta Mitchell was recognized as a distinct species in the 1970s, was introduced into the United States as a water-garden plant in the 1980s, and has escaped and spread across the southeastern United States in the 1990s. It is recognized by federal agency as noxious aquatic weed. S. minima Baker was discovered in Arkansas in 1998. A status survey of eastern Arkansas was undertaken from 1998 - 2000 to determine the distribution and abundance of S. minima and S. molesta. A search of33 Arkansas counties led to the discovery of -5". minima at 21 localities in 11 counties: Arkansas, Ashley, Chicot, Desha, Jefferson, Lee, Lincoln, Monroe, Phillips, Prairie, and Pulaski. No populations of S. molesta were located in 33 counties. Search efforts must extend to southwestern Arkansas in the Red River watershed to complete the survey.
