Ophioglossum, the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name Ophioglossum comes from the Greek meaning "snake-tongue". Their cosmopolitan distribution is mainly in tropical and subtropical habitats.
Dicksonia is a genus of tree ferns in the order Cyatheales. It is regarded as related to Cyathea, but is considered to retain more primitive traits, dating back at least to the Jurassic and Cretaceous periods. The fossil record includes stems, pinnules, and spores.
The Hymenophyllaceae, the filmy ferns and bristle ferns, are a family of two to nine genera and about 650 known species of ferns, with a subcosmopolitan distribution, but generally restricted to very damp places or to locations where they are wetted by spray from waterfalls or springs. Fossil evidence shows that ferns of the family Hymenophyllaceae have existed since at least the Upper Triassic.
Plagiogyria is a genus of ferns, the only genus in family Plagiogyriaceae in the Pteridophyte Phylogeny Group classification of 2016. Alternatively, the family may be treated as the subfamily Plagiogyrioideae of a very broadly defined family Cyatheaceae, the placement used for the genus in Plants of the World Online as of November 2019.
Trichomanes is a genus of ferns in the family Hymenophyllaceae, termed bristle ferns. The circumscription of the genus is disputed. All ferns in the genus are filmy ferns, with leaf tissue typically 2 cells thick. This thinness generally necessitates a permanently humid habitat, and makes the fronds somewhat translucent. Because of this membrane-like frond tissue, the plant is prone to drying out. “Filmy ferns” in the taxa Hymenophyllaceae grow in constantly wet environments. Many are found in cloud forests such as “Choco” in Colombia. There are also members of the taxa that can grow submersed in water.
The Lomariopsidaceae is a family of ferns with a largely tropical distribution. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Polypodiineae of the order Polypodiales. Alternatively, it may be treated as the subfamily Lomariopsidoideae of a very broadly defined family Polypodiaceae sensu lato.
Crepidomanes is a genus of ferns in the family Hymenophyllaceae. It is mostly distributed through the old world but has one species Crepidomanes intricatum in North America. The genus includes the following taxa according to Ebihara et al. 2006.
Didymochlaena is a genus of ferns. In the Pteridophyte Phylogeny Group classification of 2016, it is the only genus in the family Didymochlaenaceae. Alternatively, the family may be placed in a very broadly defined family Polypodiaceae sensu lato as the subfamily Didymochlaenoideae.
The Leptopteris is a small genus of ferns native to the New Guinea, Australia, New Zealand, and the Pacific Islands. They are similar to ferns in the related genus Todea, and were originally included in that genus. However, the very thin fronds of Leptopteris differ from the thick leathery fronds of Todea, and the genera are considered distinct. A probable extinct species, Leptopteris estipularis is known from the Early Cretaceous of India.
Lonchitis is a neotropical genus of ferns. It is the sole genus in the family Lonchitidaceae. At one time Lonchitis was placed in the Dennstaedtiaceae, and then transferred to the Lindsaeaceae, before being placed in its own family.
Didymoglossum is a tropical genus of ferns in the family Hymenophyllaceae. It comprises more than 30 epilithic or low-epiphytic species under two subgenera. The genus is accepted in the Pteridophyte Phylogeny Group classification of 2016, but not by some other sources which sink it into a broadly defined Trichomanes.
Plenasium is a genus of ferns in the family Osmundaceae. It is recognized in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), but kept within a more broadly circumscribed genus Osmunda by other sources. The genus is known from Early Cretaceous to present.
Polyphlebium is a fern genus in the family Hymenophyllaceae. The genus is accepted in the Pteridophyte Phylogeny Group classification of 2016 but not by some other sources.
Vandenboschia is a fern genus in the family Hymenophyllaceae. The genus is accepted in the Pteridophyte Phylogeny Group classification of 2016 but not by some other sources.
Abrodictyum is a fern genus in the family Hymenophyllaceae. The genus is accepted in the Pteridophyte Phylogeny Group classification of 2016 but not by some other sources, which sink it into a broadly defined Trichomanes.
Odontosoria is a genus of ferns in the family Lindsaeaceae.
Pterozonium is a genus of ferns in the subfamily Pteridoideae of the family Pteridaceae. Species are mainly found in north-western South America, as well as Costa Rica.
Syngramma is a genus of ferns in the subfamily Pteridoideae of the family Pteridaceae. Species are native to south-east tropical Asia and the Pacific.
Polytaenium is a genus of ferns in the subfamily Vittarioideae of the family Pteridaceae. Species are native to Mexico and Southern America.
Hymenophyllum axsmithii is an extinct species of fern in the family Hymenophyllaceae related to the modern hayscented ferns. The species is known from fossil fronds found in early Eocene sites of northern Washington state, United States, and central British Columbia, Canada. The species is included in Hymenophyllum subgenus Sphaerocionium, with a suggestion to be closest to a group of tropical species in the subgenus that are all specialized as sheltered epiphytes.
