Editing Selaginella (section)

== Taxonomy ==
{{More citations needed section|date=April 2021}}
Some scientists still place the Selaginellales in the class [[Lycopodiopsida]] (often misconstructed as "Lycopsida").{{citation needed|date=June 2014}}<ref>{{Cite book |last=Clugston |first=M. |title=Dictionary of Science |publisher=Penguin Reference Library |year=2014 |isbn=978-0-141-98682-1 |edition=4th |location=London |pages=743 |language=en}}</ref><ref>{{Cite book |last=Walker |first=Peter |title=Chambers Science and Technology Dictionary |publisher=Chambers |year=1992 |isbn=0-550-13239-2 |edition=4th |location=Edinburgh NewYork |pages=999 |language=en}}</ref> Some modern authors recognize three generic divisions of ''Selaginella'': ''Selaginella'', ''Bryodesma'' <small>Sojak 1992</small>, and ''Lycopodioides'' <small>Boehm 1760</small>.  ''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|date=October 2019}}

The first major attempt to define and subdivide the group was by [[Palisot de Beauvois]]<ref>Palisot de Beauvois (1805): ''Prodrome des cinquième et sixième familles de l'Æthéogamie, les mousses, les lycopodes.''</ref> 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 ''Gymnogynum'' was another monotypic genus, but that name is superseded by his own earlier name of ''Didiclis''.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''. [[Antoine Frédéric Spring|Spring]] inflated the genus ''Selaginella'' to hold all selaginelloid species four decades later.

Phylogenetic studies by Korall & Kenrick<ref>{{Citation |last1=Korall |first1=P. |last2=Kenrick |first2=P. |year=2002 |title=Phylogenetic relationships in Selaginellaceae based on ''rbcL'' sequences |journal=American Journal of Botany |volume=89 |issue=3 |pages=506–17 |name-list-style=amp |doi=10.3732/ajb.89.3.506|pmid=21665649 |doi-access=free }}</ref><ref>Korall & Kenrick (2004): The phylogenetic history of Selaginellaceae based on DNA sequences from the plastid and nucleus: extreme substitution rates and rate heterogeneity. ''Molecular Phylogenetics and Evolution'', Volume 31, Issue 3, June 2004, Pages 852–864</ref> 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]]'' <small>Jermy</small> 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.<ref name=":0" />

{| class="wikitable"
|-
! colspan=1 |  Walton & Aston 1938<ref>Verdoorn, F., ed. (1938): Manual of Pteridology: J. Walton and A. H. G. Alston, Lycopodinae, pp. 500–506. Martinus Nijhoff, The Hague. 640pp, HB.</ref>
! colspan=1 | Weststrand & Korall 2016 <ref>{{Citation |last1=Weststrand |first1=Stina |last2=Korall |first2=Petra |year=2016 |title=A subgeneric classification of ''Selaginella'' (Selaginellaceae) |journal=American Journal of Botany |volume=103 |issue=12 |pages=2160–2169 |doi=10.3732/ajb.1600288|pmid=27999080 |url=http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-300731 |doi-access=free }}</ref>
|-
| style="vertical-align:top|
* 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''
|
* 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'' [incl. ''S.'' section ''Megalosporum'', ''S.'' section ''Myosurus'']
*** subgenus ''Ericetorum'' [''S.'' section ''Lyallia'']
** clade B
*** subgenus ''Stachygynandrum'' [incl. ''S.'' (''Boreoselaginella''), ''S.'' (''Pulviniella''), ''S.'' (''Heterostachys'')]
|}

=== Zhang & Zhou, 2015 classification ===
<ref name=Zhang />
* subgenus: ''Selaginella'' Type: ''S. selaginoides'' <small>(L.) P.Beauv. ex Mart. & Schrank</small>
* subgenus: ''Boreoselaginella'' Type: ''S. sanguinolenta'' <small>(L.) Spring</small>
* subgenus: ''Ericetorum'' Type: ''S. uliginosa'' <small>(Labill.) Spring</small>
** section: ''Lyallia'' Type: ''S. uliginosa'' <small>(Labill.) Spring</small>
** section: ''Myosurus'' Type: ''S. myosurus'' <small>Alston</small>
** section: ''Megalosporarum'' Type: ''S. exaltata'' <small>(Kunze) Spring</small>
** section: ''Articulatae'' Type: ''S. kraussiana'' <small>(Kunze) A.Braun</small>
** section: ''Homoeophyllae'' Type: ''S. rupestris'' <small>(L.) Spring</small> (=''Bryodesma'' <small>Sojak</small> or ''Tetragonostachys'' <small>Jermy</small>)
** section: ''Lepidophyllae'' Type: ''S. lepidophylla'' <small>(Hook. & Grev.) Spring</small>
* subgenus: ''Pulviniella'' Type: ''S. pulvinata'' <small>(Hook. & Grev.) Maxim</small>
* subgenus: ''Heterostachys'' Type: ''S. heterostachys'' <small>Baker</small>
** section: ''Oligomacrosporangiatae''  Type: ''Selaginella uncinata'' <small>(Desv. ex Poir.) Spring</small>
** section: ''Auriculatae'' Type: ''S. douglasii'' <small>(Hook. & Grev.) Spring</small>
** section: ''Homostachys'' Type: : ''S. helvetica'' <small>(L.) Link</small>
** section: ''Tetragonostachyae'' Type: ''S. proniflora'' <small>(L.) Baker</small>
** section: ''Heterostachys''  Type: ''S. brachystachya'' <small>(Hook. & Grev.) Spring</small>
* subgenus: ''Stachygynandrum'' Type: ''S. flabellata'' <small>(L.) Spring</small>
** section: ''Plagiophyllae'' Type: ''S. biformis'' <small>A.Braun ex Kuhn</small>
** section: ''Circinatae'' Type: ''S. involvens'' <small>(Sw.) Spring</small>
** section: ''Heterophyllae'' Type: ''S. flexuosa'' <small>Spring</small>
** section: ''Austroamericanae'' Type: ''S. hartwegiana'' <small>Spring</small>
** section: ''Pallescentes'' Type: ''S. pallescens'' (C.Presl) <small>Spring</small>
** section: ''Proceres'' Type: ''S. oaxacana'' <small>Spring</small>
** section: ''Ascendentes'' Type: ''S. alopecuroides'' <small>Baker</small>

{| class="wikitable"
|-
! colspan=1 | Zhang & Zhou 2015<ref name=Zhang>{{Citation |last1=Zhou |first1=Xin-Mao |last2=Zhang |first2=Li-Bing |year=2015 |title=A classification of ''Selaginella'' (Selaginellaceae) based on molecular (chloroplast and nuclear), macromorphological, and spore features |journal=Taxon |volume=64 |issue=6 |pages=1117–1140 |doi=10.12705/646.2|s2cid=90451945 |doi-access=free }}</ref>
! colspan=1 | Zhou & Zhang 2023<ref name=":0">{{Citation |last1=Zhou |first1=Xin-Mao |last2=Zhang |first2=Li-Bing |year=2023 |title=Phylogeny, character evolution, and classification of Selaginellaceae (lycophytes) |journal=Plant Diversity |volume= 45|issue= 6|pages= 630–684|doi=10.1016/j.pld.2023.07.003 |doi-access=free |pmid=38197007 |pmc=10772194 |bibcode=2023PlDiv..45..630Z }}</ref>
|-
| style="vertical-align:top|
{{Clade | style=font-size:90%;line-height:80%
|label1=''Selaginella''
|1={{clade
  |1=subgenus ''Selaginella''
  |2={{clade
 |1=subgenus ''Boreoselaginella''
    |2={{clade
      |1={{clade
        |label1=subgenus
        |sublabel1=''Gymnogynum''
        |1={{clade
          |1={{clade
            |1={{clade
           |1=section ''Megalosporum''
              |2={{clade
             |1=section ''Myosurus''
             |2=section ''Lyallia''
                 }}
               }}
            |2=section ''Articulatae''
             }}
          |2={{clade
         |1=section ''Lepidophyllae''
         |2=section ''Homeophyllae''
             }}
           }}
         }}
   |2={{clade
     |1=subgenus ''Pulviniella''
  |2={{clade
    |label1=subgenus
    |sublabel1=''Heterostachys''
          |1={{clade
            |1={{clade
              |1=section ''Tetragonostachyae''
              |2=section ''Heterostachys''
               }}
            |2={{clade
              |1={{clade
                |1=section ''Auriculatae''
                |2=section ''Homostachys''
                 }}
              |label2=section
              |sublabel2=''Oligomacrosporangiatae''
              |2={{clade
                |1=''S. braunii'' subclade
                |2={{clade
                  |1=''S. willdenowii'' subclade
                  |2={{clade
                    |1=''S. pennata'' subclade
                    |2={{clade
                      |1=''S. pervillei'' subclade
                      |2={{clade
                        |1=''S. siamensis'' subclade
                        |2=''S. delicatula'' subclade
                         }}
                       }}
                     }}
                   }}
                 }}
               }}
             }}
    |label2=subgenus
    |sublabel2=''Stachygynandrum''
          |2={{clade
            |1=section ''Plagiophyllae''
            |2={{clade
             |1=section ''Circinatae''
              |2={{clade
                |1=section ''Ascendentes''
                |2={{clade
                  |1={{clade
                    |1=section ''Proceres''
                    |2=section ''Pallescentes''
                     }}
                  |2={{clade
                    |1=section ''Austroamericanae''
                    |2=section ''Heterophyllae''
                     }}
                   }}
                 }}
               }}
             }}
     }}
   }}
    }}
  }}
   }}
}}
|
{{Clade | style=font-size:90%;line-height:80%
|label1=Selaginellaceae
|1={{clade
  |1={{clade
    |label1=Selaginoidoideae
    |1=''Selaginoides'' <small>Séguier 1754</small>
     }}
  |2={{clade
    |1={{clade
      |label1=Boreoselaginelloideae
      |1=''Boreoselaginella'' <small>(Warburg 1900) Zhang & Zhou 2023</small>
       }}
    |2={{clade
      |1={{clade
        |label1=Gymnogynoideae
        |1={{clade
          |1={{clade
            |1=''Afroselaginella'' <small>Zhang & Zhou 2023</small>
            |2=''Megaloselaginella'' <small>Zhang & Zhou 2023</small>
             }}
          |2={{clade
            |1={{clade
              |1=''Ericetorum'' <small>(Jermy 1986) Zhang & Zhou 2023</small>
              |2=''Gymnogynum'' <small>Palisot de Beauvois 1804</small>
               }}
            |2={{clade
              |1=''Lepidoselaginella'' <small>Zhang & Zhou 2023</small>
              |2=''Bryodesma'' <small>Soják 1992</small>
               }}
             }}
           }}
         }}
      |2={{clade
        |1={{clade
          |label1=Pulvinielloideae
          |1=''Pulviniella'' <small>(Zhang & Zhou 2015) Zhang & Zhou 2023</small>
          |label2=Sinoselaginelloideae
          |2={{clade
            |1=''Sinoselaginella'' <small>Zhang & Zhou 2023</small>
            |2={{clade
              |1=''Austroselaginella'' <small>Zhang & Zhou 2023</small>
              |2=''Korallia'' <small>Zhang & Zhou 2023</small>
               }}
             }}
           }}
        |2={{clade
          |label1=Lycopodioidoideae
          |1={{clade
            |1={{clade
              |1={{clade
                |1=''Valdespinoa'' <small>Zhang & Zhou 2023</small>
                |2=''Lycopodioides'' <small>Boehm. 1760 ex Kuntze 1891</small>
                 }}
              |2=''Didiclis'' <small>Palisot de Beauvois ex Mirb. 1802</small>
               }}
            |2=''Hypopterygiopsis'' <small>Sakurai 1943</small>
             }}
          |label2=Selaginelloideae
          |2={{clade
            |1=''Chuselaginella'' <small>Zhang & Zhou 2023</small>
            |2={{clade
              |1=''Kungiselaginella'' <small>Zhang & Zhou 2023</small>
              |2={{clade
                |label1=''Selaginella''
                |1={{clade
                  |1={{clade
                    |1={{clade
                      |1=section ''Proceres'' <small>Spring 1850</small>
                      |2=section ''Pallescentes'' <small>Zhang & Zhou 2015</small>
                       }}
                    |2=section ''Austroamericanae'' <small>Zhang & Zhou 2015</small>
                     }}
                  |2=section ''Heterophyllae'' <small>Spring 1840</small>
                   }}
                 }}
               }}
             }}
           }}
         }}
       }}
     }}
   }}
}}
|}

=== Species ===
{{Main|List of Selaginella species}}
[[File:Selaginella canaliculata.jpeg|thumb|''Selaginella canaliculata'']]
[[File:Selaginella selaginoides - Niitvälja bog.jpg|thumb|''Selaginella selaginoides'']]
[[File:Iridescent fern.jpg|thumb|''Selaginella willdenowii'' is known for its iridescent colours]]
There are about 750 known species of ''Selaginella''.<ref name="Christenhusz-Byng2016">{{cite journal |author1=Christenhusz, M. J. M. |author2=Byng, J. W.  |name-list-style=amp | year = 2016 | title = The number of known plants species in the world and its annual increase | journal = Phytotaxa | volume = 261 | pages = 201–217 | url = http://biotaxa.org/Phytotaxa/article/download/phytotaxa.261.3.1/20598 | doi = 10.11646/phytotaxa.261.3.1 | issue = 3 | doi-access = free }}</ref> They show a wide range of characters; the genus is overdue for a revision which might include subdivision into several genera.{{citation needed|date=October 2019}} Species of spikemoss include:
* ''[[Selaginella apoda]]'' – meadow spikemoss; eastern [[North America]]
* ''[[Selaginella arizonica]]'' <small>Maxon</small> – west Texas to Arizona and Sonora, Mexico
* ''[[Selaginella asprella]]''
* ''[[Selaginella bifida]]'' – [[Rodrigues Island]]
* ''[[Selaginella biformis]]''
* ''[[Selaginella bigelovii]]''
* ''[[Selaginella braunii]]'' – Braun's spikemoss; [[China]]
* ''[[Selaginella bryopteris]]'' – sanjeevani; [[India]]
* ''[[Selaginella canaliculata]]'' – clubmoss; [[southeast Asia]], [[Maluku Islands]]
* ''[[Selaginella carinata]]''
* ''[[Selaginella cinerascens]]''
* ''[[Selaginella densa]]'' – lesser spikemoss; western North America
* ''[[Selaginella denticulata]]''
* ''[[Selaginella eclipes]]'' – hidden spikemoss; eastern North America
* ''[[Selaginella elmeri]]''
* ''[[Selaginella eremophila]]'' <small>Maxon</small>
* ''[[Selaginella erythropus]]''
* ''[[Selaginella galotteii]]''
* ''[[Selaginella gigantea]]'' – From Venezuela.
* ''[[Selaginella hansenii]]''
* ''[[Selaginella kraussiana]]'' – Krauss's spikemoss; [[Africa]], [[Azores]]
* ''[[Selaginella lepidophylla]]'' – resurrection plant, dinosaur plant, and flower of stone; [[Chihuahuan Desert]], [[North America]]
* ''[[Selaginella martensii]]'' – variegated spikemoss
* ''[[Selaginella moellendorffii]]''
* ''[[Selaginella oregana]]''
* ''[[Selaginella plana]]'' – Asian spikemoss; tropical [[Asia]]
* ''[[Selaginella poulteri]]''
* ''[[Selaginella pulcherrima]]''
* ''[[Selaginella rupestris]]'' – rock spikemoss, festoon pine, and northern Selaginella (eastern North America)
* ''[[Selaginella rupincola]]'' <small>Underw.</small> – west Texas to Arizona and Sonora, Mexico
* ''[[Selaginella selaginoides]]'' – lesser clubmoss; north temperate [[Europe]], [[Asia]] and [[North America]])
* ''[[Selaginella sericea]]'' <small>[[A.Braun]]</small> – [[Ecuador]]
* ''[[Selaginella serpens]]''
* ''[[Selaginella sibirica]]''
* ''[[Selaginella stellata]]'' – starry spikemoss; Mexico, [[Central America]]
* ''[[Selaginella substipitata]]''
* ''[[Selaginella tamariscina]]''
* ''[[Selaginella tortipila]]''
* ''[[Selaginella uliginosa]]'' – [[Australia]]
* ''[[Selaginella umbrosa]]''
* ''[[Selaginella uncinata]]'' – peacock moss, peacock spikemoss, blue spikemoss
* ''[[Selaginella underwoodii]]'' <small>Hieron.</small> – west Texas to Wyoming and west into Arizona
* ''[[Selaginella wallacei]]''
* ''[[Selaginella watsonii]]''
* ''[[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]] plants that appear at first glance to be [[fern]]s.