Cytotaxonomy and phylogeny of heterosporous ferns
Madhusoodanan, P.V.; Sevichan, P.J.; Rejani, A.
Journal of Economic and Taxonomic Botany 15(1): 243-249
Biosystematics of heterosporous ferns (Marsileales and Salviniales) is analysed with special stress on cytology. The phylogeny of this group traditionally suggested as related to Schizaeales and Hymenophyllales is contradicted. Instead, affinity with heterosporous fern allies (Selaginellales and Isoetales) is suggested on the basis of cytological and morphological evidences. Marsileales are distinct and unrelated to Salviniales, Azolla is distinct from Salvinia, sufficiently enough to consider under a separate family. New phyletic lines for this group are suggested.