Spikemoss

Taxobox
name = Spikemoss

---

image_width = 240px
regnum = Plantae
divisio = Lycopodiophyta
classis = Selaginellopsida
ordo = Selaginellales
familia = Selaginellaceae
genus = "Selaginella"
subdivision_ranks = Species
subdivision = See text.

Spikemoss refers to any plant of the genus "Selaginella" in the family Selaginellaceae. Many workers still place the Selaginellales in the class Lycopsida (modern nomenclature: Lycopodiopsida). This group of plants is included in what, for convenience, is called "fern allies".

The spikemosses are creeping or ascendant plants with simple, scale-like leaves on branching stems from which roots also arise. The plants are heterosporous (megaspores and microspores), and have structures called ligules, scale-like outgrowths near the base of the upper surface of each microphyll and sporophyll.

Unusually for the lycopods, each microphyll contains a branching vascular trace.

There are about 700 species of "Selaginella", showing 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 braunii" -- Arbor-vitae Fern (China)
*"Selaginella bryopteris" -- Sanjeevani (India)
*"Selaginella canaliculata" -- Clubmoss (southeast Asia, Moluccas)
*"Selaginella densa" -- Lesser Spikemoss (western North America)
*"Selaginella eclipes" -- Hidden Spikemoss (eastern North America)
*"Selaginella kraussiana" -- Krauss's Spikemoss (Africa, Azores)
*"Selaginella lepidophylla" -- "resurrection plant", "dinosaur plant" North America
*"Selaginella moellendorffii" -- Whole genome sequence released. See the [http://wiki.genomics.purdue.edu/index.php/Selaginella "Selaginella" Wiki] administered by the Purdue Genomics Database facility, or browse the genome at the US Department of Energy's [http://genome.jgi-psf.org/Selmo1/Selmo1.home.html Joint Genome Institute] site.
*"Selaginella rupestris" -- Rock Spikemoss or Festoon Pine (eastern North America)
*"Selaginella selaginoides" -- Lesser Clubmoss (north temperate Europe, Asia and North America)
*"Selaginella uncinata" -- Peacock Fern
*"Selaginella willdenovii" -- Electric Fern

Many 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.