The taxonomy of Dryopteris inaequalis complex is reviewed. The use of a large sample size permitted quantification of variation within and among groups. Phenetic methods in this study revealed the existence of six groups, five formerly described taxa and one new taxon, D. pseudopentheri sp. ined. The new species is defined on both macromorphological grounds. Dryopteris lewelleana Pic.Serm. and d. inaequalis (Schltdl.) Kuntze var. atropaleacae Schelpe are placed in synonymy under D.fadenii Pic.Serm. and D.inaequalis respectively. The phylogeny of the complex is reconstructed using cladistic analysis of morphological characters. Dryopteris manniana (Hook.) C.Chr., the probabl sister species is used as an outgroup for the analysis. Phylogenetic analysis revealed that there are four monphyletic species and two metataxa in the complex. Evidence from Scanning Electron Microscopy, micromorphology, macromorphology and cytology is used as a basis for classification. Trichome characters, indusium, spore and guard-cell sizes proved to be of great taxonomic utility in defining species and cytotypes in the complex. Guard-cell and spore sizes in the different taxa are positively correlated to ploidal level. Illustrations of some microcharacters are provided. The taxonomic treatment includes a key, descriptions of the species based on the characters studied and a distribution map.

Bibliography: leaves 58-64.