Asplenium | |
---|---|
Maidenhair spleenwort ( Asplenium trichomanes ssp. quadrivalens) | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Division: | Polypodiophyta |
Class: | Polypodiopsida |
Order: | Polypodiales |
Suborder: | Aspleniineae |
Family: | Aspleniaceae |
Genus: | Asplenium L. |
Type species | |
Asplenium marinum | |
Species | |
About 700, but see text. | |
Synonyms | |
and see text |
Asplenium is a genus of about 700 species of ferns, often treated as the only genus in the family Aspleniaceae, though other authors consider Hymenasplenium separate, based on molecular phylogenetic analysis of DNA sequences, a different chromosome count, and structural differences in the rhizomes. The type species for the genus is Asplenium marinum .
The most common vernacular name is spleenworts, applied to the more "typical" species. A. nidus and several similar species are called bird's-nest ferns , the Camptosorus group is known as walking ferns , and distinct names are applied to some other particularly well-known species.
Many groups of species have been separated from Asplenium as segregate genera. These include Camptosorus, Ceterach, Phyllitis, and Tarachia, but these species can form hybrids with other Asplenium species and because of this are usually included in a more broadly defined Asplenium. [1]
Some of the older classifications elevate the Aspleniaceae to the taxonomic rank of order as Aspleniales. The newer classifications place it in the subordinal group called eupolypods within the order Polypodiales. Within the eupolypods, Aspleniaceae belongs to a clade informally and provisionally known as eupolypods II.
It has been found that in some species, the chloroplast genome has evolved in complex and highly unusual ways. This makes standard cladistic analyses unsuited to resolve the phylogeny of that particular group of ferns, and even very sophisticated computational phylogenetics methods yield little information. In addition to hybridization running rampant in parts of this genus, there are also some species like the mother spleenwort (A. bulbiferum) or A. viviparum which mainly reproduce asexually, essentially cloning themselves over and over again. While most are diploid or tetraploid, some species (e.g. A. shuttleworthianum ) are octoploid. [2]
Both the scientific name and the common name "spleenwort" are derived from an old belief, based on the doctrine of signatures, that the fern was useful for ailments of the spleen, [3] due to the spleen-shaped sori on the backs of the fronds. "-wort" is an ancient English term that simply means "plant" (compare German -wurz). The plants were thought to cause infertility in women. [3]
Vitruvius relates the story of the name thus:
... certain pastures in Crete, on each side of the river Pothereus, which separates the two Cretan states of Gnosus and Gortyna. There are cattle at pasture on the right and left banks of that river, but while the cattle that feed near Gnosus have the usual spleen, those on the other side near Gortyna have no perceptible spleen. On investigating the subject, physicians discovered on this side a kind of herb which the cattle chew and thus make their spleen small. The herb is therefore gathered and used as a medicine for the cure of splenetic people. The Cretans call it ἄσπληνον. – via Wikisource.
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A few of these ferns have some economic importance in the horticulture trade. The bird's-nest ferns ( A. nidus and several very similar, closely related species) are commonly found for sale as a house plant. The Australian mother spleenwort (A. bulbiferum) is sometimes available at greenhouses, and is of interest, along with the related A. viviparum , for the many small bulblets borne on the fronds that may grow into new plants. This characteristic is also shared with the eastern North American walking fern (A. rhizophyllum) and several Mexican species including A. palmeri . The ebony spleenwort A. platyneuron is also sometimes sold in nurseries as a hardy plant. However, many spleenworts are epipetric or epiphytic and difficult to cultivate.
Asplenium species are used as food plants by the larvae of some Lepidoptera species including Batrachedra bedelliella which feeds exclusively on A. nidus. For diseases of Asplenium, see List of foliage plant diseases (Polypodiaceae).
The Aspleniaceae (spleenworts) are a family of ferns, included in the order Polypodiales. The composition and classification of the family have been subject to considerable changes. In particular, there is a narrow circumscription, Aspleniaceae s.s., in which the family contains only two genera, and a very broad one, Aspleniaceae s.l., in which the family includes 10 other families kept separate in the narrow circumscription, with the Aspleniaceae s.s. being reduced to the subfamily Asplenioideae. The family has a worldwide distribution, with many species in both temperate and tropical areas. Elongated unpaired sori are an important characteristic of most members of the family.
Asplenium nidus is an epiphytic species of fern in the family Aspleniaceae, native to tropical southeastern Asia, eastern Australia, Hawaii, Polynesia, Christmas Island, India, and eastern Africa. It is known by the common names bird's-nest fern or simply nest fern.
Asplenium scolopendrium, commonly known as the hart's-tongue fern, is an evergreen fern in the family Aspleniaceae native to the Northern Hemisphere.
The flora of Saint Helena, an isolated island in the South Atlantic Ocean, is exceptional in its high level of endemism and the severe threats facing the survival of the flora. In phytogeography, it is in the phytochorion St. Helena and Ascension Region of the African Subkingdom, in the Paleotropical Kingdom.
Asplenium bulbiferum, known as mother spleenwort, is a fern species native to New Zealand only. It is also called hen and chicken fern and, in the Māori language, pikopiko, mouku or mauku. Its fronds are eaten as a vegetable.
Asplenium rhizophyllum, the (American) walking fern, is a frequently-occurring fern native to North America. It is a close relative of Asplenium ruprechtii which is found in East Asia and also goes by the common name of "walking fern".
Asplenium ceterach, also known as the rustyback fern, is a fern species in the spleenwort family Aspleniaceae.
Asplenium septentrionale is a species of fern known by the common names northern spleenwort and forked spleenwort. It is native to Europe, Asia and western North America, where it grows on rocks. Its long, slender leaves give it a distinctive appearance. Three subspecies exist, corresponding to a tetraploid and a diploid cytotype and their triploid hybrid.
Asplenium australasicum, the bird's nest fern or crow's nest fern, is an epiphytic Australasian species of fern in the family Aspleniaceae.
Asplenium pinnatifidum, commonly known as the lobed spleenwort or pinnatifid spleenwort, is a small fern found principally in the Appalachian Mountains and the Shawnee Hills, growing in rock crevices in moderately acid to subacid strata. Originally identified as a variety of walking fern, it was classified as a separate species by Thomas Nuttall in 1818. It is believed to have originated by chromosome doubling in a hybrid between walking fern and mountain spleenwort, producing a fertile tetraploid, a phenomenon known as alloploidy; however, the hypothesized parental hybrid has never been located. It is intermediate in morphology between the parent species: while its leaf blades are long and tapering like that of walking fern, the influence of mountain spleenwort means that the blades are lobed, rather than whole. A. pinnatifidum can itself form sterile hybrids with several other spleenworts.
Asplenium antiquum is a fern of the family Aspleniaceae, commonly known as bird's-nest ferns. In Japanese, it is known by ō-tani-watari and tani-watari. It grows on cliffs, logs and rocks, near waterfalls, in damp forests, and on tree trunks in China, Japan, Korea, and Taiwan. It is classified as an endangered species in both South Korea and Japan.
Asplenium adiantum-nigrum is a common species of fern known by the common name black spleenwort. It is found mostly in Africa, Europe, and Eurasia, but is also native to a few locales in Mexico and the United States.
Asplenium onopteris, known as the Irish spleenwort or western black spleenwort, is a species of fern mostly found throughout the Mediterranean Basin but also around the Eastern Atlantic.
Lucidus may refer to:
Asplenium appendiculatum, ground spleenwort, is a common native fern to Australia and New Zealand. It usually grows in cool damp conditions, among rocks, on logs or as an epiphyte.
Psychoides filicivora is a moth of the family Tineidae first described by Edward Meyrick in 1937. First found in Ireland in 1909, it is possible that the moth was introduced from imported ferns from Asia. The moth can be found from spring though autumn in a series of generations. The species overwinters as a larva.
Psychoides verhuella is a moth of the family Tineidae found in Europe. It was first described in 1853, by Charles Théophile Bruand d'Uzelle from a specimen from Besançon, France. It is the type species of the genus Psychoides, also raised by Charles Bruand in 1853. The larvae feed on ferns.