etails (often treated as ferns), and lycophytes (clubmosses, spikemosses, and quillworts) are all pteridophytes. However, they do not form a monophyletic group because ferns (and horsetails) are more closely related to seed plants than to lycophytes. "Pteridophyta" is thus no longer a widely accepted taxon, but the term pteridophyte remains in common parlance, as do pteridology and pteridologist as a science and its practitioner, respectively. Ferns and lycophytes share a life cycle and are often collectively treated or studied, for example by the International Association of Pteridologists and the Pteridophyte Phylogeny Group.Pteridophytes are the first true land plants: ... They are seedless, vascular cryptogams: ... They show true alternation of generations: ... Sporophyte has true roots, stem and leaves: ... Spores developed in sporangia are homosporous or heterosporous: ... Sporangia are produced in groups on sporophylls: