Selaginella
Selaginella is a genus of lycophytes commonly known as spike mosses. The genus includes around 700 species of primitive vascular plants that are found in a wide range of habitats in most regions of the world.
Spike mosses are spore producing plants and are most closely related to quillworts. Selaginella is the single remaining genus from the order of plants known as Selaginellales. One species, Selaginella lepidophylla, has a remarkable ability to tolerate drought and has earned the name ‘resurrection plant’.
Growth form
Selaginella plants often resemble ferns due to the pattern of their branching and leaves. They can either grow as an upright, branching plant or along the ground with creeping stems. Roots grow directly from the stems of creeping plants.
The leaves of Selaginella species are simple and scale-like. As with all lycophytes, their leaves have only a single vein and are known as microphylls. In some species, the leaves of shaded plants produce a blue sheen which often fades as the leaves age or the plant becomes exposed to light. The leaves that support the plants spores are usually clumped together to form a cone-like structure called a strobili.
Distribution of selaginella
Spike mosses are found in most parts of the world and can tolerate a massive range of climates. They are found from the Arctic to the tropics but are most common in tropical regions.
Selaginella species can be found in both very humid and very dry environments and in both open and shaded habitats. For example, different species can be found in tropical rainforest and in North American deserts.
Diversity and taxonomy
In total there is around 700 species in the genus Selaginella. They sit within the division of plants known as Lycophyta and the class Isotopsida, which includes the quillworts (Isoetes). Selaginella is the sole genus from the family Selaginellaceae and the order Selaginellales.
Evolution of selaginella
Selaginella is the sole remaining genus from a once far more diverse group of plants. There have been a number of attempts to date the evolution of the family Selaginellaceae and most figures tend to estimate their evolution to around 400 million years ago.
Reproduction of selaginella
The spike mosses reproduce with spores. They have distinct male and female spores known as microspores and megaspores, respectively. Spore are produced on leaves in enclosures called sporangia. The spores of Selaginella species are both pollinated and dispersed by wind.
Resurrection plant
The resurrection plant, Selaginella lepidophylla, is famous for its ability to appear to come back from the dead. It has an incredible ability to tolerate draught and can remarkably grow fresh, green leaves after multiple years of zero rain.
During a drought, the plant turns brown and curls up into a ball. Once it is exposed to water, it slowly opens up revealing healthy, green shoots within its center.
Last edited: 31 May 2015