any member of the plant genus Selaginella of the order Selaginellales with more than 700 species of mossy, in some cases fernlike, perennials. They are widely distributed in all parts of the world, particularly in the tropics. Many are forest plants; some grow on trees, but others thrive in dry or seasonally dry areas. They bear scalelike leaves, either spirally arranged or in ranks of four, on trailing, climbing, or erect stems and branches. The spore-bearing leaves are similar to ordinary leaves but are clustered in spikes, or strobili.
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