some areas (like in New South Wales, Australia), due to threats of habitat loss and low population numbers. Evolution and fossil record Fossil species have not been transferred to Aglaomorpha in PPG I, and are still recorded in the genus Drynaria. In 2010, twelve well-preserved fossil specimens were described from the Sanying Formation of the Yangjie coal mine of China. Named Drynaria callispora, it comes from the Piacenzian age of the Pliocene epoch (about 3.6 to 2.5 million years ago). The fossil record of drynarioids is not very well documented due to the typically poor preservation of fossils recovered. Previous fossil species assigned to Drynaria include Drynaria astrostigma, D. dura, and D. tumulosa from the Cenomanian of the Czech Republic; and D. durum, all assigned tentatively to the genus in 1899. The arrangement and type of their sori, however, indicate that they are members of the family Matoniaceae instead. Outside the genus, Protodrynaria takhtajani from the Eocene-Oligocene boundary of Kursk Oblast, Russia shows some affinities to Drynaria but only distantly. The only other reasonably convincing fossil remains of drynarioids aside from D. callispora was a specimen named Polypodium quercifolia recovered in 1985 from the Late Miocene (23.03 to 5.332 million years ago) of Palembang, Indonesia. These were later transferred to the living species Aglaomorpha heraclea. It remains, as of 2011, the oldest known drynarioid. See also Platycerium – staghorn or elkhorn ferns Asplenium – spleenworts, bird's-nest ferns, and walking ferns Polypodium – rockcap ferns References Aglaomorpha Epiphytes Medicinal plants Fern genera