Spikemoss Temporal range: | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Lycophytes |
Class: | Lycopodiopsida |
Order: | Selaginellales Prantl |
Family: | Selaginellaceae Willk. |
Genus: | Selaginella P. Beauv. |
Type species | |
Selaginella selaginoides | |
Species | |
See text. | |
Synonyms | |
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Selaginella, also known as spikemosses or lesser clubmosses is a genus of lycophyte. It is usually treated as the only genus in the family Selaginellaceae, with over 750 known species.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having spores of two types. They are sometimes included in an informal paraphyletic group called the "fern allies". The species S. moellendorffii is an important model organism. Its genome has been sequenced by the United States Department of Energy's Joint Genome Institute. [1] The name Selaginella was erected by Palisot de Beauvois solely for the species Selaginella selaginoides , which turns out (with the closely related Selaginella deflexa ) to be a clade that is sister to all other Selaginellas, so any definitive subdivision of the species into separate genera leaves two taxa in Selaginella, with the hundreds of other species in new or resurrected genera.
Selaginella occurs mostly in the tropical regions of the world, with a handful of species to be found in the arctic-alpine zones of both hemispheres. [2] Fossils assignable to the modern genus are known spanning over 300 million years from the Late Carboniferous to the present. [3]
Selaginella species are creeping or ascendant plants with simple, scale-like leaves (microphylls) on branching stems from which roots also arise. The stems are aerial, horizontally creeping on the substratum (as in Selaginella kraussiana ), sub-erect ( Selaginella trachyphylla ) or erect (as in Selaginella erythropus ). The vascular steles are polystelic protosteles. Stem section shows the presence of more than two protosteles. Each stele is made up of diarch (having two strands of xylem [4] ) and exarch (growing outward in) xylems.[ citation needed ] The steles are connected with the cortex by means of many tube-like structures called trabeculae, which are modified endodermal cells with casparian strips on their lateral walls.[ citation needed ] The stems contain no pith.[ citation needed ]
In Selaginella, each microphyll and sporophyll has a small scale-like outgrowth called a ligule at the base of the upper surface. [5] : 7 The plants are heterosporous with spores of two different size classes, known as megaspores and microspores. [6]
Unusual for the lycopods, which nearly always have microphylls with a single unbranched vein, the microphylls of a few Selaginella species contain a branched vascular trace. [7]
Under dry conditions, some species of Selaginella can survive dehydration. In this state, they may roll up into brown balls and be uprooted, but can rehydrate under moist conditions, become green again and resume growth. This phenomenon is known as poikilohydry, and poikilohydric plants such as Selaginella bryopteris are sometimes referred to as resurrection plants. [8]
There is no evidence of whole genome duplication in Selaginella's evolutionary history. Instead they have gone through tandem gene duplications, which is particularly noticeable in genes relevant for desiccation tolerance. [9] [ jargon ]
This section needs additional citations for verification .(April 2021) |
Some scientists still place the Selaginellales in the class Lycopodiopsida (often misconstructed as "Lycopsida").[ citation needed ] [10] [11] Some modern authors recognize three generic divisions of Selaginella: Selaginella, BryodesmaSojak 1992, and LycopodioidesBoehm 1760. Lycopodioides would include the North American species S. apoda and S. eclipes, while Bryodesma would include S. rupestris (as Bryodesma rupestre). Stachygynandrum is also sometimes used to include the bulk of species.[ citation needed ]
The first major attempt to define and subdivide the group was by Palisot de Beauvois [12] in 1803–1805. He established the genus Selaginella as a monotypic genus, and placed the bulk of species in Stachygynandrum. Gymnogynum was another monotypic genus, but that name is superseded by his own earlier name of Didiclis. This turns out, today, to be a group of around 45–50 species also known as the Articulatae, since his genus Didiclis/Gymnogynum was based on Selaginella plumosa . He also described the genus Diplostachyum to include a group of species similar to Selaginella apoda. Spring inflated the genus Selaginella to hold all selaginelloid species four decades later.
Phylogenetic studies by Korall & Kenrick [13] [14] determined that the Euselaginella group, comprising solely the type species, Selaginella selaginoides and a closely related Hawaiian species, Selaginella deflexa , is a basal and anciently diverging sister to all other Selaginella species. Beyond this, their study split the remainder of species into two broad groups, one including the Bryodesma species, the Articulatae , section Ericetorum Jermy and others, and the other centered on the broad Stachygynandrum group.
In 2023, Zhou & Zhang suggested that the genus should be broken up into 19 different genera. [15]
Walton & Aston 1938 [16] | Weststrand & Korall 2016 [17] |
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There are about 750 known species of Selaginella. [19] They show a wide range of characters; the genus is overdue for a revision which might include subdivision into several genera.[ citation needed ] Species of spikemoss include:
A few species of Selaginella are desert plants known as "resurrection plants", because they curl up in a tight, brown or reddish ball during dry times, and uncurl and turn green in the presence of moisture. Other species are tropical forest plants that appear at first glance to be ferns.
A number of Selaginella species are popular plants for cultivation, mostly tropical species. Some of the species popularly cultivated and actively available commercially include:
Lycopodiopsida is a class of vascular plants also known as lycopsids, lycopods, or lycophytes. Members of the class are also called clubmosses, firmosses, spikemosses and quillworts. They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the stems at the bases of the leaves. Although living species are small, during the Carboniferous, extinct tree-like forms (Lepidodendrales) formed huge forests that dominated the landscape and contributed to coal deposits.
Lycopodium is a genus of clubmosses, also known as ground pines or creeping cedars, in the family Lycopodiaceae. Two very different circumscriptions of the genus are in use. In the Pteridophyte Phylogeny Group classification of 2016, Lycopodium is one of nine genera in the subfamily Lycopodioideae, and has from nine to 15 species. In other classifications, the genus is equivalent to the whole of the subfamily, since it includes all of the other genera. More than 40 species are accepted.
Lycopodiella is a genus in the clubmoss family Lycopodiaceae. The genus members are commonly called bog clubmosses, describing their wetland habitat. The genus has a cosmopolitan distribution, with centers of diversity in the tropical New World and New Guinea. In the past, the genus was often incorporated within the related genus Lycopodium, but was segregated in 1964. In the Pteridophyte Phylogeny Group classification of 2016, Lycopodiella is placed in the subfamily Lycopodielloideae, along with three other genera. In this circumscription, the genus has about 15 species. Other sources use a wider circumscription, in which the genus is equivalent to the Lycopodielloideae of PPG I, in which case about 40 species and hybrids are accepted.
The Athyriaceae are a family of terrestrial ferns in the order Polypodiales. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Aspleniineae, and includes two genera. Alternatively, it may be treated as the subfamily Athyrioideae of a very broadly defined family Aspleniaceae. The family has with a cosmopolitan distribution.
Selaginella lepidophylla, also known as a resurrection plant, is a species of desert plant in the spikemoss family (Selaginellaceae). It is native to the Chihuahuan Desert of the United States and Mexico. S. lepidophylla is renowned for its ability to survive almost complete desiccation. Resurrection plants are vascular rooted plants capable of surviving extreme desiccation, then resuming normal metabolic activity upon rehydration. The plant's hydro-responsive movements are governed by stem moisture content, tissue properties and a graded distribution of lignified cells affecting concentric stem stiffness and spiraling. During dry weather in its native habitat, its stems curl into a tight ball, uncurling only when exposed to moisture.
Selaginella apoda, commonly known as meadow spikemoss, is a perennial lycophyte native to much of the eastern United States and parts of northeastern Mexico. The life cycle is the shortest of the genus Selaginella, as well as one of the shortest among the lycophytes. Selaginella apoda is found primarily in damp soils in habitats such as swamps, wet fields, open woods and along stream banks. Selaginella apoda presents the potential for case studies involving the plant's adaptability to environmental toxins. It is closely related to Selaginella eclipes and S. ludoviciana, with both of which it has been reported to form hybrids. This group is characterized by relatively flat strobili and large megasporophylls which occur in the same plane as the lateral leaves.
Selaginella selaginoides is a non-flowering plant of the spikemoss genus Selaginella with a wide distribution around the Northern Hemisphere. It resembles a moss in appearance but is a vascular plant belonging to the division Lycopodiophyta. It has a number of common names including lesser clubmoss, club spikemoss, northern spikemoss, low spikemoss and prickly mountain-moss. This plant has one close relative, Selaginella deflexa, native to Hawaii. These two plants form a small clade that is sister to all other Selaginella species.
Rose of Jericho or Jericho rose may refer to:
Selaginella kraussiana is a species of vascular plant in the family Selaginellaceae. It is referred to by the common names Krauss' spikemoss, Krauss's clubmoss, or African clubmoss, and is found naturally in parts of Sub-Saharan Africa and in Macaronesia. It is sometimes given the misnomer of “peacock fern”, due to its lacy leaf structure, despite having no relation to actual ferns; rather, it belongs to the very ancient lineage of plants known as the clubmosses.
Dendrolycopodium obscurum, synonym Lycopodium obscurum, commonly called rare clubmoss, ground pine, or princess pine, is a North American species of clubmoss in the family Lycopodiaceae. It is a close relative of other species such as D. dendroideum and D. hickeyi, also treelike. It is native to the eastern United States and southeastern Canada from Georgia to Minnesota to Nova Scotia. It grows in the understory of temperate coniferous and deciduous forests, where it is involved in seral secondary succession, growing in clonal colonies some years after disturbance has occurred. It has also been found in Japan, Taiwan, Korea, Russian Far East, and northeastern China.
Selaginella uliginosa is a small plant in the spikemoss family Selaginellaceae which is endemic to Australia. An ancient and primitive plant, usually under 10 centimetres tall, it is often seen in sunny moist areas. The specific epithet uliginosa is from Latin, referring to the plant's preference for growing in swampy locations.
Selaginella denticulata, or Mediterranean clubmoss, is a non-flowering plant of the spikemoss genus Selaginella with a wide distribution around the Northern Hemisphere.
Selaginella stellata, also recognized by its common name, starry spikemoss or starry spike-moss, is a species of spikemoss of the family Selaginellaceae. It is a type of lycopod that grows naturally in Mexico and Central American countries like Guatemala and Belize and can also be found in the state of Hawaii.
Selaginella tortipila is a species of clubmoss in the family Selaginellaceae. It is referred to by the common names twistedhair spikemoss or kinky-hair spike-moss, and is a member of an early diverging group of plants. It is native to the Southeastern United States where it is found in a small area in the Southern Appalachian Mountains and Piedmont. It is found on granite or sandstone rock outcrop communities, often at high elevation.
Selaginella tamariscina is a species of plant in the Selaginellaceae family, endemic to China, India, Japan, Korea, Philippines, Russia (Siberia), Taiwan, and northern Thailand. It is an evergreen perennial growing to 45 cm in height. It is often used as an herbal medicine, and has been used to treat gout and hyperuricemia.
The Melaniellaceae are a family of fungi in the division Basidiomycota and order of Doassansiales. The family contains 1 genera and 2 species. They have a distribution in south and south-east Asia.
Selaginella deflexa, commonly known as deflexed spikemoss, is a non-flowering species of plant in the spikemoss genus Selaginella and is in the subgenus of the same name. It is closely related to Selaginella selaginoides which is the only other member in its subgenus. It is endemic to Hawaii and grows primarily in the wet tropical biome from 1,050–1,500 m (3,440–4,920 ft). can be found on all major islands except for Lana'i. It is usually found growing in wet moss. Unlike most members of Selaginella,S. deflexa does not have rhizophores along its stem. It gets its name from its reflexed leaves which point outwards.