Description

Ledge spike-moss (Selaginella rupestris), the northern selaginella sometimes locally known as rock spike-moss, is a species of spike-moss occurring in dry rocky places in eastern North America, including one locality in Greenland. It has a wide but sporadic range. In the absence of water, it rolls into a ball for which, it is also known as bird nest moss. Again, when it comes in contact with water, it opens up. 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" Selaginella rupestris is an important model organism. The name Selaginella was erected by Palisot de Beauvois solely for the species Selaginella selaginoides, which turns out 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.

Characteristics:

Ledge spike-moss species are creeping or ascendant plants with simple, scale-like leaves on branching stems from which roots also arise. The stems are aerial, horizontally creeping on the substratum, sub erect or erect. The vascular steles are polystelic protosteles. Stem section shows the presence of more than two protosteles. Each stele is made up of diarch(centre of origin on the inside, later cells are added centrifugally) and exarch(centre of origin located laterally, later cells are added centripedally) xylem in centre. The steles are connected with the cortex by means of many tube-like structures called trabeculae, which are modified endodermal cells with casparian strips on their lateral walls. The stems contain no pith.

Medicinal Uses:

Treatment of cardiovascular diseases and of smaller body cancers in nose, throat, lung and liver