少根紫萍（学名：Spirodela oligorrhiza）为浮萍科紫萍属下的一个种。

Spirodela punctata (or Landoltia punctata, common name dotted duckmeat) is a species of duckweed (Lemnaceae). The species is morphologically intermediate between Lemna and other species of Spirodela. In 1999 D.H. Les and D.J. Crawford proposed segregating the species to a new genus Landoltia containing just the species L. punctata, on the basis of biochemical and DNA studies.