Psilotum nudum | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Division: | Polypodiophyta |
Class: | Polypodiopsida |
Order: | Psilotales |
Family: | Psilotaceae |
Genus: | Psilotum |
Species: | P. nudum |
Binomial name | |
Psilotum nudum | |
Synonyms [2] | |
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Psilotum nudum, the whisk fern, [2] is a fernlike plant. Like the other species in the order Psilotales, it lacks roots. [3]
Its name, Psilotum nudum, means "bare naked" in Latin, because it lacks (or seems to lack) most of the organs of typical vascular plants, as a result of evolutionary reduction. (Note that leaves are not actually absent, but greatly reduced.) [3]
The embryo has only two parts, a distal shoot apex and a proximal foot. The shoot apex produces a rhizome without roots, possibly because P. nudum and relatives are often epiphytes. The rhizome in turn will eventually produce greatly reduced leaves instead of roots. These processes are heavily influenced by auxin concentrations. [4]
P. nudum is found in tropical Africa, Central America, tropical and subtropical North America, South America, [5] tropical Asia, Australia, Hawaii, southern Japan, Lord Howe Island, New Zealand, with a few isolated populations in SW Europe ("Los Alcornocales", Spain, Cádiz province). [6] [7] Although most weeds are flowering plants, P. nudum is an unusual example of a weed because it is both nonflowering and rootless. [8]
In tropical areas, this plant is often epiphytic, whilst in more temperate areas, such as south-eastern Australia, it is usually found growing in rock crevices. [7] Thousands of people per day walk by these plants at the Sydney Opera House forecourt. [9]
The plant, which grows wild in southern Japan, was once much cultivated in Japanese gardens as an ornamental plant. Slightly over 100 garden varieties were given fantastic names. [10] [11] Called matsubaran ("pine-needle orchid") in Japanese, it was one of the noble plants in the Edo period (1603–1867).
The species is naturally found on all the main Hawaiian Islands. Known locally as Moa because of its chicken feet like stems, the Hawaiians collected large quantities of the spores and used them like talcum powder, [12] under the loincloth to prevent chafing. The spores were also used medicinally as a purge. Children would play a game called 'moa nahele' or cockfighting with the branch stems. Twigs of the Moa were interlocked and the players pulled on the ends. The loser's twig broke and the winner crowed like a rooster. [13] The species is still often used in making traditional Hawaiian leis.
Its common name, whisk fern, alludes to its use in the past as a small broom, made by tying a handful of its branches together. [14] It is sometimes found in cultivation (either accidentally, as a weed in greenhouses, or deliberately, in the form of a number of cultivars). [5]
It may prove to be a good source of antimicrobial chemicals. [15]
The tree ferns are arborescent (tree-like) ferns that grow with a trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae, Dicksoniaceae, Metaxyaceae, and Cibotiaceae. It is estimated that Cyatheales originated in the early Jurassic, and is the third group of ferns known to have given rise to tree-like forms. The others are the extinct Tempskya of uncertain position, and Osmundales where the extinct Guaireaceae and some members of Osmundaceae also grew into trees. In addition there were the Psaroniaceae and Tietea in the Marattiales, which is the sister group to most living ferns including Cyatheales.
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.
Psilotum is a genus of fern-like vascular plants. It is one of two genera in the family Psilotaceae commonly known as whisk ferns, the other being Tmesipteris. Plants in these two genera were once thought to be descended from the earliest surviving vascular plants, but more recent phylogenies place them as basal ferns, as a sister group to Ophioglossales. They lack true roots and leaves are very reduced, the stems being the organs containing photosynthetic and conducting tissue. There are only two species in Psilotum and a hybrid between the two. They differ from those in Tmesipteris in having stems with many branches and a synangium with three lobes rather than two.
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.
Platycerium is a genus of about 18 fern species in the polypod family, Polypodiaceae. Ferns in this genus are widely known as staghorn or elkhorn ferns due to their uniquely shaped fronds. This genus is epiphytic and is native to tropical and temperate areas of South America, Africa, Southeast Asia, Australia, and New Guinea.
Cibotium, also known as manfern, is a genus of 11 species of tropical tree ferns. It is the only genus in family Cibotiaceae in the Pteridophyte Phylogeny Group classification of 2016. Alternatively, the family may be treated as the subfamily Cibotioideae of a very broadly defined family Cyatheaceae, the family placement used for the genus in Plants of the World Online as of November 2019.
Nephrolepis exaltata, known as the sword fern or Boston fern, is a species of fern in the family Lomariopsidaceae. It is native to the Americas. This evergreen plant can reach as high as 40–90 centimetres (16–35 in), and in extreme cases up to 1.5 metres. It is also known as the Boston sword fern, wild Boston fern, Boston Blue Bell Fern, tuber ladder fern, or fishbone fern.
Psilotaceae is a family of ferns consisting of two genera, Psilotum and Tmesipteris with about a dozen species. It is the only family in the order Psilotales.
Pteridium aquilinum, commonly called bracken, brake, common bracken, and also known as eagle fern, is a species of fern occurring in temperate and subtropical regions in both hemispheres. Originally native to Eurasia and North America, the extreme lightness of its spores has led to it achieving a cosmopolitan distribution.
Nephrolepis is a genus of about 30 species of ferns. It is the only genus in the family Nephrolepidaceae, placed in the suborder Aspleniineae of the order Polypodiales in the Pteridophyte Phylogeny Group classification of 2016. The genus is commonly referred to as macho ferns or Boston ferns. The fronds are long and narrow, and once-pinnate, in the case of one Bornean species reaching thirty feet in length.
Moa are extinct giant flightless birds native to New Zealand.
Asparagus aethiopicus, Sprenger's asparagus, is a plant native to the Cape Provinces and the Northern Provinces of South Africa. Often used as an ornamental plant, it is considered an invasive weed in many locations. Asparagus fern, asparagus grass and foxtail fern are common names; however, it is unrelated to true ferns. A. aethiopicus has been confused with A. densiflorus, now regarded as a separate species, so that information about A. aethiopicus will often be found under the name A. densiflorus.
Psilotum complanatum, the flatfork fern, is a rare herbaceous epiphytic fern ally in the genus Psilotum. There is some evidence that it might be a true fern that has lost some typically fern-like characteristics. Morphologically, the plant is simple, lacking leaves and roots, and having hanging stems with dichotomous branching, which lack developed leaves but have minute scales. The stems and branches have protostele, with a triangular-shaped core of xylem. The scales are arranged in two rows along the flat stems and branches. The stems are broadly triangular in cross section and 5 mm wide. The branches are 1.5 to 2 mm wide. P. complanatum grows 10 to 75 cm long and stems branch in pairs a number of times up their length and are covered with brownish colored hair-like rhizoids. Small stalks end with simple sporangia from the axils of minute bifid, rounded sporophylls. Bean shaped, monolete spores are produced. The spores germinate best in a dark environment when ammonium is present. The gametophyte is non-photosynthetic, living in association with a fungus for its nutritional needs. Plants grow from a subterranean rhizome which anchors the plant in place and absorbs nutrients by means of filament like rhizoids.
Nothocestrum is a genus of flowering plants in the nightshade family, Solanaceae. It contains four species of large shrubs or small trees that are endemic to Hawaii, where they are known as ʻaiea.
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.
Nephrolepis cordifolia, is a fern native to the global tropics, including northeastern Australia and Asia. It has many common names including fishbone fern, tuberous sword fern, tuber ladder fern, erect sword fern, narrow sword fern and ladder fern, and herringbone fern. It is similar to the related fern Nephrolepis exaltata.
Tmesipteris obliqua, more commonly known as the long fork-fern or common fork-fern, is a weeping, epiphytic fern ally with narrow unbranched leafy stems. T. obliqua is a member of the genus Tmesipteris, commonly known as hanging fork-ferns. Tmesipteris is one of two genera in the order Psilotales, the other genus being Psilotum. T. obliqua is endemic to eastern Australia.
Crepidomanes minutum is small fern in the filmy fern family which grows throughout the Pacific. It is commonly referred to as tiny bristle fern. The specific epithet 'minutum' means small in Latin, referring to the small fronds
Nephrolepis brownii, the Asian sword fern, is a species of fern native to Asia and introduced elsewhere.