What is "neviusia"

Neviusia, the snow-wreaths, is a genus of ornamental plants, which are native to the United States, containing two extant species and one extinct species known from leaf fossils. This genus is a rare example of a disjunct range occurring in North America. The type species, Neviusia alabamensis, occurs in several southeastern states, while second extant species, Neviusia cliftonii, is endemic to the Mt Shasta region of California, and the extinct species Neviusia dunthornei is found in shale deposits in the Okanagan Highlands of Washington and British Columbia.