3 species from North American and eastern Asia, with strange, paired leaves joined around the petiole and different shapes of lobing, similar to Podophyllum. White flowers above the foliage, often followed by bloomy-blue fruits, similar to Mahonia. All are in the family Berberidaceae and some sources include Diphylleia in the genus Podophyllum.
Growing in deep shade the flowers are attractive to the relatively small number of flies and bees that will forage in such places. The berries are likely to be edible to birds in common with other members of the barberry family. The large leaves provide useful shelter for amphibians as well as a whole range of ground-dwelling invertebrates.