The ferns and fern allies of the karst forests of Bohol Island, Philippines

We provide the first and only comprehensive list of the ferns and fern allies of Bohol island. Philippines. This compendium is based on collections made from those of Cuming in 1841 to our recent survey of the karst Forests of the Rajah Sikatuna Protected Landscape (RSPL) and vicinity during November. 2003 to Feburary 2004. A total of 169 species in 63 genera and 27 families are reported here for the island, of which 91 species are new additions. Twenty-one species are Philippine endemics, five of which are previously known only from types or from very few collections. They are Ctenitis hoholensis, C. humilis, Pteris whitfiordii, Antrophyum williamsii, and Lomagramma merrillii. Bohol is the the locality of five fern names, namely, Ctenitis humilis. C. boholaosis, Cyclosorus glaber and Thelypteris sevillana (= Pneumatopteris glabra). Cyclosorus boholensis Copel. (= Sphaerostephanos acrostichoides), and Diplazium petiolore. Two species in the genera Oleandra and Ctenitis and several specimens of Selaginelle remain undetermined. Nineteen previously reported,species have not been recollected or in some cases, their taxonomic identities are doubtful. Prior to this study, only one fern specimen from Bohol was accessioned at the Philippine National Herbarium (PNH). All historical collections are currently deposited in herbaria in the U.S.A. and Europe. Boholonas have successfully maintained the integrity of the wild populations of ferns especially those species that are heavily collected in other parts of the Philippines for their ormamental value.