Diplazium molokaiense
 Diplazium molokaiense is a rare species of fern known by the common name Molokai twinsorus fern. It is endemic to Hawaii where it is one of the rarest ferns. It has historically been found on the islands of Kauai Oahu Lanai Molokai and Maui but it is thought to have been extirpated from four of them and today it only exists on Maui. There are fewer than 70 individual plants remaining there. The fern was federally listed as an endangered species of the United States in 1994.