Nephrophyllidium
Nephrophyllidium is a monotypic genus of aquatic flowering plants in the family Menyanthaceae. The sole species is Nephrophyllidium crista-galli. They are wetland plants with basal reniform and crenate leaves. Flowers are five-parted and white, and the petals are adorned with lateral wings and a midline keel. "Nephrophyllidium" is most nearly related to "Menyanthes", which is very similar in habit. The genus name is derived from the kidney-shaped leaves ( = kidney and "phyllon" = leaf), and the specific epithet refers to the curled petal edges ( = cockscomb). "Nephrophyllidium crista-galli" is found in the Pacific Northwest of  America, and in Japan, where it can be called subspecies "japonicum" (Franch.) Yonek. & H.Ohashi. "Nephrophyllidium" is commonly known as deer cabbage. The IAPT determined that a prior synonym for the genus, "Fauria" Franch., too closely resembled the genus "Faurea" (Proteaceae), and thus conserved "Nephrophyllidium" as the accepted genus name.