The ferns are a group of vascular plants that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissues that conduct water and nutrients and in having life cycles in which the branched sporophyte is the dominant phase.
Isoetes, commonly known as the quillworts, is a genus of lycopod. It is the only living genus in the family Isoetaceae and order Isoetales. There are currently 192 recognized species, with a cosmopolitan distribution mostly in aquatic habitats but with the individual species often scarce to rare. Some botanists split the genus, separating two South American species into the genus Stylites, although molecular data place these species among other species of Isoetes, so that Stylites does not warrant taxonomic recognition. Species virtually identical to modern quillworts have existed since the Jurassic epoch, though the timing of the origin of modern Isoetes is subject to considerable uncertainty.
The order Salviniales is an order of ferns in the class Polypodiopsida.
Marattiaceae is the only family of extant (living) ferns in the order Marattiales. In the Pteridophyte Phylogeny Group classification of 2016, Marattiales is the only order in the subclass Marattiidae. The family has six genera and about 110 species. Many are different in appearance from other ferns, having large fronds and fleshy rootstocks.
Marsileaceae is a small family of heterosporous aquatic and semi-aquatic ferns, though at first sight they do not physically resemble other ferns. The group is commonly known as the "pepperwort family" or as the "water-clover family" because the leaves of the genus Marsilea superficially resemble the leaves of a four-leaf clover. In all, the family contains 3 genera and 50 to 80 species with most of those belonging to Marsilea.
Archaeopteris is an extinct genus of progymnosperm tree with fern-like leaves. A useful index fossil, this tree is found in strata dating from the Upper Devonian to Lower Carboniferous, the oldest fossils being 385 million years old, and had global distribution.
Equisetidae is one of the four subclasses of Polypodiopsida (ferns), a group of vascular plants with a fossil record going back to the Devonian. They are commonly known as horsetails. They typically grow in wet areas, with whorls of needle-like branches radiating at regular intervals from a single vertical stem.
The Cyatheaceae are a family of ferns, the scaly tree ferns, one of eight families in the order Cyatheales in the Pteridophyte Phylogeny Group classification of 2016. Alternatively, the family may defined much more broadly as the only family in the Cyatheales, with the PPG I family treated as the subfamily Cyatheoideae. The narrower circumscription is used in this article.
Danaea is a fern genus of approximately 50 species in the eusporangiate fern family Marattiaceae. They are small to intermediately large ferns with erect or creeping rhizomes and usually once-pinnate leaves with opposite pinnae. The fertile leaves are contracted, acrostichoid and covered below with sunken, linear synangia. The genus Danaea has a neotropical distribution, occurring from southern Mexico through Central America, the Caribbean and northern South America to Bolivia, Paraguay and the Mata Atlantica in Brazil and Northern Argentina. There is also a population on Isla del Coco in the Pacific.
Eusporangiate ferns are vascular spore plants, whose sporangia arise from several epidermal cells and not from a single cell as in leptosporangiate ferns. Typically these ferns have reduced root systems and sporangia that produce large amounts of spores.
The Polypodiidae, commonly called leptosporangiate ferns, formerly Leptosporangiatae, are one of four subclasses of ferns, the largest of these being the largest group of living ferns, including some 11,000 species worldwide. The group has also been treated as the class Pteridopsida or Polypodiopsida, although other classifications assign them a different rank. Older names for the group include Filicidae and Filicales, although at least the "water ferns" were then treated separately.
Lindsaeaceae is a pantropical family of ferns in the order Polypodiales. It contains six or seven genera with about 220 known species, some of which also extend into the more temperate regions of eastern Asia, New Zealand, and South America.
Psaronius is an extinct genus marattialean tree fern which grew to 10m in height, and is associated with leaves of the organ genus Pecopteris and other extinct tree ferns. Originally, Psaronius was a name for the petrified stems, but today the genus is used for the entire tree fern. Psaronius tree fern fossils are found from the Carboniferous through the Permian.
Ptisana salicina, or king fern, is a species of fern native to Norfolk Island, New Zealand and the South Pacific. Large and robust with a distinctive tropical appearance, it has fronds up to 5 metres tall that arise from a starchy base that was a traditional food for the Maori. It has several other common names including para, tawhiti-para, and horseshoe fern.
Angiopteris is a genus of huge evergreen ferns from the family Marattiaceae, found throughout the paleotropics from Madagascar to the South Pacific islands. Species of smaller stature with elongate synangia and creeping rhizomes are sometimes segregated into the genus Archangiopteris, and a once-pinnate monotypic segregate genus has been called Macroglossum, but molecular data supports inclusion of these taxa within a broad concept of Angiopteris.
Eupodium is a genus of ferns in the family Marattiaceae native to the Neotropics. Traditionally, many taxonomists have included Eupodium within the genus Marattia. However, molecular phylogenetic studies and morphological studies of extant and fossil taxa support the recognition of Eupodium as a lineage distinct from Marattia. Morphologically, Eupodium was thought to be distinct among the Marattiaceae in only having one frond at a time, bearing awns along veins, and having stalked synangia. However, recent phylogenetic work found that an additional species native to Brazil, Eupodium cicutifolium, which lacks these characters, is also genetically in Eupodium, making the genus challenging to distinguish morphologically. Eupodium cicutifolium does occasionally have short-stalked synangia, and has spinulose spores like the other Eupodium species, but is otherwise easily mistaken for a Marattia or Ptisana. The genus currently has four recognized species.
Marattia is a small genus of primitive, large, fleshy eusporangiate ferns. It is the type genus of the family Marattiaceae, order Marattiales and class Marattiopsida. Formerly considered to be a much larger genus, genetic analysis has shown that Marattia in the broad sense was paraphyletic, and subsequently the genera Ptisana and Eupodium were split off. Except for one species in Hawaii, the genus is neotropical.
Dr Maarten Joost Maria Christenhusz is a Dutch botanist, natural historian and photographer.
Christensenia is the scientific name of two genera of organisms and may refer to:
Antrophyopsis is a genus of vittarioid ferns, a member of subfamily Vittarioideae and family Pteridaceae. Like other vittarioids, ferns in the genus are epiphytes with simple, straplike leaves. They are native to tropical Africa and islands of the Indian Ocean. The presence of a midrib in their leaves, the shape of their spores, and the shape of cells at the tip of their paraphyses help to distinguish members of the genus from other vittarioids. The group was raised to the level of genus in 2016.
