Selaginella

Spikemoss Temporal range: Late Carboniferous–Recent PreꞒ Ꞓ O S D C P T J K Pg N
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
Bryodesma Soják 1992 Carpolepidium Palisot de Beauvois 1805 Didiclis Palisot de Beauvois 1803 Diplostachyum Palisot de Beauvois 1805 Gymnogynum Palisot de Beauvois 1804 Heterophyllae Spring 1840 Heterophyllium Hieronymus ex Börner 1912 Homoeophyllae Spring 1840 Homostachys Warburg 1900 Hypopterygiopsis Sakurai 1943 Lycopodioides Boehm. 1760 ex Kuntze 1891 Mirmau Adanson 1763 Polycocca Hill 1773 nom. superfl. Selaginoides Séguier 1754 nom. rej. Selago Browne 1756 nom. ill. Stachygynandrum Palisot de Beauvois 1804 nom. rej. Trispermium Hill 1773

Selaginella is the sole genus in the family Selaginellaceae, the spikemosses or lesser clubmosses, a kind of vascular plant.

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'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]