We describe a new species of the genus Selaginella from Arunachal Pradesh. The proposed taxon is collected from hill slopes of Wakka, a town in Longding district of Arunachal Pradesh, India. The described species is based on variation in spore morphology and features of median leaves. The variation recorded in spore morphology came into light when freshly collected samples were analysed under an electron microscope. The species is morphologically distinct and is very close to two species i.e., S. reticulata and S. odishana. Taxonomic keys and a table are added to separate and compare the three species respectively. Diagnosis, description and relevant photo plates are provided for easy identification of the species.