''Selaginella'' is the sole genus of
vascular plant
Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They ...
s in the family Selaginellaceae, the spikemosses or lesser clubmosses.
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". ''
S. moellendorffii'' is an important
model organism. Its genome has been sequenced by the
United States Department of Energy
The United States Department of Energy (DOE) is an executive department of the U.S. federal government that oversees U.S. national energy policy and manages the research and development of nuclear power and nuclear weapons in the United Stat ...
's
Joint Genome Institute. 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.
Description
''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
Diarchy (from Greek , ''di-'', "double", and , ''-arkhía'', "ruled"),Occasionally misspelled ''dyarchy'', as in the ''Encyclopaedia Britannica'' article on the colonial British institution duarchy, or duumvirate (from Latin ', "the office of ...
(having two strands of xylem) and
exarch
An exarch (;
from Ancient Greek ἔξαρχος ''exarchos'', meaning “leader”) was the holder of any of various historical offices, some of them being political or military and others being ecclesiastical.
In the late Roman Empire and ea ...
(growing outward in)
xylem
Xylem is one of the two types of transport tissue in vascular plants, the other being phloem. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients. The word ''xylem'' is derived fr ...
s. 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. The stems contain no pith.
In ''Selaginella'', each microphyll and sporophyll has a small scale-like outgrowth called a
ligule A ligule (from "strap", variant of ''lingula'', from ''lingua'' "tongue") is a thin outgrowth at the junction of leaf and leafstalk of many Poaceae, grasses (Poaceae) and Cyperaceae, sedges. A ligule is also a strap-shaped extension of the corolla ...
at the base of the upper surface.
The plants are
heterosporous
Heterospory is the production of spores of two different sizes and sexes by the sporophytes of land plants. The smaller of these, the microspore, is male and the larger megaspore is female. Heterospory evolved during the Devonian period from ...
with spores of two different size classes, known as megaspores and microspores.
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.
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.
Taxonomy
Some scientists still place the Selaginellales in the class
Lycopodiopsida (often misconstructed as "Lycopsida"). Some modern authors recognize three generic divisions of ''Selaginella'': ''Selaginella'', ''Bryodesma''
Sojak 1992, and ''Lycopodioides''
Boehm 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.
The first major attempt to define and subdivide the group was by
Palisot de Beauvois
Ambroise Marie François Joseph Palisot, Baron de Beauvois (27 July 1752, in Arras – 21 January 1820, in Paris) was a French naturalist and zoologist.
Palisot collected insects in Oware, Benin, Saint Domingue, and the United States, from 17 ...
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 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
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having ...
'' species, the ''
Articulatae'', section ''
Ericetorum''
Jermy and others, and the other centered on the broad ''Stachygynandrum'' group.
Walton & Aston classification
In the ''Manual of Pteridology'', the following classification was used by Walton & Alston:
genus: ''Selaginella''
*subgenus: ''Euselaginella''
**group: ''selaginoides''
**group: ''pygmaea''
**group: ''uliginosa'' (''Ericetorum'')
**group: ''rupestris'' (''Tetragonostachys'' or ''Bryodesma'')
*subgenus: ''Stachygynandrum''
**series: ''Decumbentes''
**series: ''Ascendentes''
**series: ''Sarmentosae''
**series: ''Caulescentes''
**series: ''Circinatae''
**series: ''Articulatae''
*subgenus: ''Homostachys''
*subgenus: ''Heterostachys''
However, this is now known to be highly paraphyletic in most of its groupings. Two recent classifications, employing modern methods of phylogenetic analysis, are as follows:
Weststrand & Korall, 2016 classification
genus: ''Selaginella''
* subgenus: ''Selaginella''
* clade: "Rhizophoric clade"
** clade A
*** subgenus ''Rupestrae''
'Bryodesma'' Sojak or ''Tetragonostachys'' Jermy, ''S.'' section ''Homeophyllae''*** subgenus ''Lepidophyllae''
'S.'' section ''Lepidophyllae''*** subgenus ''Gymnogynum''
'S.'' section ''Articulatae''*** subgenus ''Exaltatae''
ncl. ''S.'' section ''Megalosporum'', ''S.'' section ''Myosurus''*** subgenus ''Ericetorum''
'S.'' section ''Lyallia''** clade B
*** subgenus ''Stachygynandrum''
ncl. ''S.'' (''Boreoselaginella''), ''S.'' (''Pulviniella''), ''S.'' (''Heterostachys'')
Zhang & Zhou, 2015 classification
genus: ''Selaginella''
* subgenus: ''Selaginella'' Type: ''S. selaginoides''
(L.) P.Beauv. ex Mart. & Schrank
* subgenus: ''Boreoselaginella'' Type: ''S. sanguinolenta''
(L.) Spring
* subgenus: ''Ericetorum'' Type: ''S. uliginosa''
(Labill.) Spring
** section: ''Lyallia'' Type: ''S. uliginosa''
(Labill.) Spring
** section: ''Myosurus'' Type: ''S. myosurus''
Alston
** section: ''Megalosporarum'' Type: ''S. exaltata''
(Kunze) Spring
** section: ''Articulatae'' Type: ''S. kraussiana''
(Kunze) A.Braun
** section: ''Homoeophyllae'' Type: ''S. rupestris''
(L.) Spring (=''Bryodesma''
Sojak or ''Tetragonostachys''
Jermy)
** section: ''Lepidophyllae'' Type: ''S. lepidophylla''
(Hook. & Grev.) Spring
* subgenus: ''Pulviniella'' Type: ''S. pulvinata''
(Hook. & Grev.) Maxim
* subgenus: ''Heterostachys'' Type: ''S. heterostachys''
Baker
** section: ''Oligomacrosporangiatae'' Type: ''Selaginella uncinata''
(Desv. ex Poir.) Spring
** section: ''Auriculatae'' Type: ''S. douglasii''
(Hook. & Grev.) Spring
** section: ''Homostachys'' Type: : ''S. helvetica''
(L.) Link
** section: ''Tetragonostachyae'' Type: ''S. proniflora''
(L.) Baker
** section: ''Heterostachys'' Type: ''S. brachystachya''
(Hook. & Grev.) Spring
* subgenus: ''Stachygynandrum'' Type: ''S. flabellata''
(L.) Spring
** section: ''Plagiophyllae'' Type: ''S. biformis''
A.Braun ex Kuhn
** section: ''Circinatae'' Type: ''S. involvens''
(Sw.) Spring
** section: ''Heterophyllae'' Type: ''S. flexuosa''
Spring
** section: ''Austroamericanae'' Type: ''S. hartwegiana''
Spring
** section: ''Pallescentes'' Type: ''S. pallescens'' (C.Presl)
Spring
** section: ''Proceres'' Type: ''S. oaxacana''
Spring
** section: ''Ascendentes'' Type: ''S. alopecuroides''
Baker
Species
There are about 750 known species of ''Selaginella''.
They show a wide range of characters; the genus is overdue for a revision which might include subdivision into several genera. Better-known spikemosses include:
*''
Selaginella apoda'' – meadow spikemoss; eastern
North America
*''
Selaginella arizonica
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having ...
''
Maxon – west Texas to Arizona and Sonora, Mexico
*''
Selaginella asprella''
*''
Selaginella bifida
''Selaginella bifida'' is a lycophyte native to Rodrigues Island in the Mascarene Islands
The Mascarene Islands (, ) or Mascarenes or Mascarenhas Archipelago is a group of islands in the Indian Ocean east of Madagascar consisting of the islan ...
'' –
Rodrigues Island
*''
Selaginella biformis''
*''
Selaginella bigelovii
''Selaginella bigelovii'' is a species of spikemoss known by the common names bushy spikemoss and Bigelow's spikemoss. It is native to California and Baja California, where it grows in rocky places in many different habitat types, from the coastl ...
''
*''
Selaginella braunii'' – Braun's spikemoss;
China
*''
Selaginella bryopteris'' – sanjeevani;
India
India, officially the Republic of India ( Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the ...
*''
Selaginella canaliculata
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having ...
'' – clubmoss;
southeast Asia
Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...
,
Maluku Islands
The Maluku Islands (; Indonesian: ''Kepulauan Maluku'') or the Moluccas () are an archipelago in the east of Indonesia. Tectonically they are located on the Halmahera Plate within the Molucca Sea Collision Zone. Geographically they are located ...
*''
Selaginella carinata
''Selaginella carinata'' is a species of plant in the Selaginellaceae family. It is endemic to Ecuador. Its natural habitat is subtropical or tropical moist montane forests and it is threatened by habitat loss
Habitat destruction (also ter ...
''
*''
Selaginella cinerascens
''Selaginella cinerascens'' is a species of spikemoss known by the common names mesa spikemoss, gray spikemoss, and ashy spikemoss. It is native to Baja California as well as some locations just north of the border in San Diego County, Californi ...
''
*''
Selaginella densa
''Selaginella densa'' is a species of spikemoss known by the common names lesser spikemoss, prairie spikemoss, and Rocky Mountains spikemoss. It is native to western North America, where it can be found from Alaska to Ontario, the Dakotas, Texas ...
'' – lesser spikemoss; western North America
*''
Selaginella denticulata
''Selaginella denticulata'', or Mediterranean clubmoss, is a non-flowering plant of the spikemoss genus ''Selaginella'' with a wide distribution around the Northern Hemisphere.
Description
It is in the genus ''Selaginella'' and this creepe ...
''
*''
Selaginella eclipes'' – hidden spikemoss; eastern North America
*''
Selaginella elmeri''
*''
Selaginella eremophila
''Selaginella eremophila'' is a species of spikemoss known by the common name desert spikemoss. It is native to the deserts and adjacent mountains around the intersection of California and Arizona with Baja California. It grows in sandy and rocky ...
''
Maxon
*''
Selaginella erythropus''
*''
Selaginella galotteii
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having ...
''
*''
Selaginella gigantea'' - From Venezuela.
*''
Selaginella hansenii
''Selaginella hansenii'' is a species of spikemoss known by the common name Hansen's spikemoss. It is endemic to California where it can be found throughout the central part of the state, from the lowest reaches of the Cascade Range through the ...
''
*''
Selaginella kraussiana'' – Krauss's spikemoss;
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
,
Azores
)
, motto=
( en, "Rather die free than subjected in peace")
, anthem=( en, "Anthem of the Azores")
, image_map=Locator_map_of_Azores_in_EU.svg
, map_alt=Location of the Azores within the European Union
, map_caption=Location of the Azores wi ...
*''
Selaginella lepidophylla
''Selaginella lepidophylla'' (syn. ''Lycopodium lepidophyllum'') is a species of desert plant in the spikemoss family (Selaginellaceae). Known as a "resurrection plant", ''S. lepidophylla'' is renowned for its ability to survive almost complete ...
'' – resurrection plant, dinosaur plant, and flower of stone;
Chihuahuan Desert
The Chihuahuan Desert ( es, Desierto de Chihuahua, ) is a desert ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of far West Texas, the middle to lower Rio Grande Valley and the lowe ...
,
North America
*''
Selaginella martensii'' – variegated spikemoss
*''
Selaginella moellendorffii''
*''
Selaginella oregana
''Selaginella oregana'' is a species of spikemoss known by the common name Oregon spikemoss. It is native to the Pacific Coast of western North America, where it can be found from British Columbia to northern California. It grows in mossy, shady ...
''
*''
Selaginella plana'' – Asian spikemoss; tropical
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...
*''
Selaginella poulteri''
*''
Selaginella pulcherrima
''Selaginella pulcherrima'' is a species of plant in the family Selaginellaceae
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lyc ...
''
*''
Selaginella rupestris'' – rock spikemoss, festoon pine, and northern Selaginella (eastern North America)
*''
Selaginella rupincola
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having ...
''
Underw. – west Texas to Arizona and Sonora, Mexico
*''
Selaginella selaginoides'' – lesser clubmoss; north temperate
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...
,
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...
and
North America)
*''
Selaginella sericea''
A.Braun –
Ecuador
Ecuador ( ; ; Quechuan languages, Quechua: ''Ikwayur''; Shuar language, Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechuan ...
*''
Selaginella serpens
''Selaginella serpens'' is a species of plant in the family Selaginellaceae: found mostly in the Caribbean.
References
serpens
Serpens ( grc, , , the Serpent) is a constellation in the northern celestial hemisphere. One of the 48 con ...
''
*''
Selaginella sibirica
''Selaginella sibirica'', the Siberian spikemoss, is a species of spikemoss
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopod ...
''
*''
Selaginella stellata
''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 li ...
'' – starry spikemoss; Mexico,
Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...
*''
Selaginella substipitata
''Selaginella substipitata'', the stalked spikemoss, is a species of plant in the Selaginellaceae family, endemic to Caribbean islands, Colombia, and Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, ...
''
*''
Selaginella tamariscina
''Selaginella tamariscina'' is a species of plant in the Selaginellaceae family, endemic to China, India, Japan, Korea, Philippines, Russia (Siberia), Taiwan, and northern Thailand
Thailand ( ), historically known as Siam () and offic ...
''
*''
Selaginella tortipila
''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 So ...
''
*''
Selaginella uliginosa
''Selaginella uliginosa'' is a small perennial plant found in Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian contin ...
'' –
Australia
*''
Selaginella umbrosa''
*''
Selaginella uncinata'' – peacock moss, peacock spikemoss, blue spikemoss
*''
Selaginella underwoodii
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses.
This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having ...
''
Hieron. – west Texas to Wyoming and west into Arizona
*''
Selaginella wallacei
''Selaginella wallacei'' is a species of spikemoss known by the common name Wallace's spikemoss. It is native to western North America from British Columbia to California to Montana, where it can be found in many types of habitat, including open ...
''
*''
Selaginella watsonii
''Selaginella watsonii'' is a species of spikemoss known by the common name Watson's spikemoss. It is native to the western United States, where it grows in many rocky habitat types, including high mountain peaks in alpine climates. This lycophyt ...
''
*''
Selaginella willdenowii'' – Willdenow's spikemoss, peacock fern; southeast Asia
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
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
plants that appear at first glance to be
fern
A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except ...
s.
Cultivation
A number of ''Selaginella'' species are popular plants for cultivation, mostly tropical species. Some of the species popularly cultivated and actively available commercially include:
*''S. kraussiana'': golden clubmoss
*''S. martensii'': frosty fern
*''S. moellendorffii'': gemmiferous spikemoss
*''S. erythropus'': red selaginella or ruby-red spikemoss
*''S. uncinata'': peacock moss
*''S. lepidophylla'': resurrection plant
*''S. braunii'': arborvitae fern
References
External links
*
*
{{Taxonbar, from=Q379743
Lycophyte genera