Selaginella had dichotomous branching and rhizomes with adventitious roots. The leaves are microsporophyllous having 2 distinct sizes known as anisophylly. Each leaf has a ligule, a small tongue-like projection at the base of the leaf. The microsporophylls have microsporangia which produce microspores. Microspores develop into male gametophytes.
Megasporophylls have megasporangia which produce megaspores.
Megaspores develop into female gametophytes. The sporangia are eusporangiate and the growth of the strobilus is apical. 1. the megasporangia are larger than the microsporangia, 2. The gametophytes exhibit primary germination, meaning that they develop within the spore wall. The male and female gametophytes are smaller in size, have a shorter existence, and are more complex.