Selaginella
Selaginella or commonly known as the Spike Mosses, are located in the genera of Lycophytes and belong to the family Selaginellaceae (Evert & Eichhon, 2013). There species of Selaginella which are native to Australia such as, Selaginella ciliaris. A distinct trait of this species is the abiltiy to 'reserrect'. This ability only occurs in certain species that are found in arid areas such as Texas, New Mexico and Mexico (Evert & Echhon, 2013). During dry periods the plant will dry out and coil into a brown ball, once water is available the plant will uncoil and become green again, this can be seen in Selaginella lepidoylla (Evert & Echhon, 2013).
Most species in Australia are listed as Not Threatened. Although there is little known about this species in Australia. There are some species listed as priority two such as Selaginella pygmaea.The species Selaginella anderwsii or commonly known as Tallebugera spikemoss is endemic to South Eastern Queensland, and is listed as vulnerable under the EPBC act.
Very little is known about these species, Although it is thought that the main threat to these species is habitat loss.
Selaginella has erect stems that are located close to the roots, and they are small to medium in size and grow upwards and outwards using stems that grow at the base of the plant (does not grow any leaves) where stems with leaves and sporangia and also roots are attached, grow in a way that each new branches are formed in two opposite each other. The stem will continuously grow upwards and branch out with two new braches forming opposite each other. The inner structure of the stem is the simplest of vascular plants, containing two tissue types for nutrient transport and three layers of tissues that encase the two transport tissues.
Selaginella has small basic leaves with a single vein, that in some species nearly cover the entire stems of the plants. The leaves grow outwards from the stems and are arranged opposite of each other. The reproductive structures are located in compact cone-like structures called strobili which occur on the tips of stems and usually have a spiralled or form a crisscross pattern.
Selaginella are heterosporous, meaning they have two kinds of sex cells are produced male and female. Both sex cells are produced in the same or different strobili, with 1 – 4 female cells produced which are larger in comparison to the male spores, which many are produced. Selaginella requires water for fertilization to occur so the sperm can swim to the fuse with the ovary.
Selaginella are mainly found in tropical habitats or where water is readily available, although there are species which inhabit arid areas. To survive in these tough conditions these species of Selaginella become dormant during the driest parts of the year. Due to this unique adaptation these ferns are commonly known as resurrection plants.
It is believed that the ancestors of Selaginella appeared during the Late Carboniferous period. This time was when lycophyte trees dominated coal-forming swamps (Evert & Eichhorn, 2013). Towards the end of the Late Carboniferous the lycophyte trees vanished due to the drying of swamps as the climate changed, leaving only few other lycophytes remaining which are similar to modern day Selaginella(Evert & Eichhorn, 2013).
Plantae
Lycopodiophyta
Selaginellaceae
Selaginella
Evert & Eichhorn, 2013, and recognized by The Integrated Taxonomic Information system (ITIS).
In Australia Selaginella occurs around coastal areas. The main areas which this species occurs is the north of Australia and throughout much of the south east. Selaginella also occurs in Tasmania and in Western Australia in parts of the south and the north in the Kimberley region.
For a distribution map of Selaginella species see Atlas of Living Australia http://bie.ala.org.au/species/Selaginella
Generally the this species prefers tropical environments where water is readily available. Native Australian species prefer damp terrestrial environments such as swamplands with rich clay or basalt soils or on rock ledges around rivers or waterfalls.
Many species of Selaginella appear in the gardens of many backyards including Selaginella willdenowii for its beautiful peacock-blue leaves. Selaginella may also have potential medicinal uses for its antioxidant properties.
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