Neither a fern (although closely related) or a moss Selaginella Martensii Jori is actually a lycophyte. The lycophytes are a very primitive group of plants that were the first known vascular plants to appear on Earth. Evolving over 400 million years ago during the Silurian Period it makes them older than the dinosaurs. The mossy looking, scaly fronds are gorgeous and have a certain look of lushness about them especially when wet. When grown as individual plants they almost look like ready made bonsai bushes. As the plants grow they become heavily branched forming a flatted fan/ plateau type affect and usually have light tips to the darker fronds. They seem to be rather popular in winter/ Christmas pot and basket displays.
They originate from Central America so do require high humidity when growing in the home, mist regularly and stand on a gravel tray that is constantly topped up with water just below the top of the gravel. Due to their high humidity requirements you may find they do better in a bottle garden or some other decorative glass container. Plant in a humus rich, moist but well drained compost and position in a bright spot but out of direct midday sun. We have managed to get these down to quite low temperatures before they have been killed off, 2c being the lowest under glass so far but outside, as soon as they get hit by the first frost then they are dead. We will keep trying to build up their cold resistance and are forever hopeful.