An order of the * Lycopsida containing two genera, Lycopodium (club mosses) and Phylloglossum, both homosporous. There are some 200 species of Lycopodium distributed worldwide. They are all herbs and have long dichotomously branching stems bearing numerous small leaves with no ligules (compare Selaginellales ). The unilocular sporangia are borne singly in the axils of sporophylls, which in many species occur together in distinctive club-shaped strobili. The free-living gametophyte may, depending on species, be either photosynthetic or saprophytic. It is always found in association with an endotrophic mycorrhiza. The antheridia, which produce many biflagellate antherozoids, are located in the centre of the apex of the prothallus and are surrounded by a ring of archegonia. Phylloglossum contains the single species P. drummondii, which is very different from Lycopodium in habit, consisting of a basal whorl of leaves and a single strobilus borne on a long stalk.
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