Lycopodiophyta, also known as lycophytes, is a group of vascular plants comprising ancient club mosses and their relatives. Some of the synonyms for lycopodiophyta include lycopsids, lycopods and lycopodiopsida. These terms refer to the same group of plants with unique features such as small needle-like leaves, primitive vascular systems, and spore-bearing structures. Other related terms include Lycopodiopsida, a class of plants within the phylum Lycopodiophyta and Selaginellales, an order of heterosporous lycophytes. Despite their ecological and evolutionary significance, lycopodiophyta is a relatively unknown group of plants with limited commercial value.