Evolution of genome space occupation in ferns: linking genome diversity and species richness.

Background And Aims: The dynamics of genome evolution caused by whole genome duplications and other processes are hypothesized to shape the diversification of plants and thus contribute to the astonishing variation in species richness among the main lineages of land plants. Ferns, the second most species-rich lineage of land plants, are highly suitable to test this hypothesis because of several unique features that distinguish fern genomes from those of seed plants. In this study, we tested the hypothesis that genome diversity and disparity shape fern species diversity by recording several parameters related to genome size and chromosome number.

Distribution of Ophioglossum reticulatum L. in South America. A case of long-distance jump dispersal?

The objective of this exploratory work is to test the hypothesis that South American populations of Ophioglossum reticulatum L. derive from Africa. Spores cross the Atlantic transported by wind and arrive in South America in recurrent migration.

Isoetes pedersenii, a new species from Southern South America.

The name Isoetes pedersenii H.P. Fuchs (Lycophyta), a species known only from the Mburucuyá National Park, Corrientes, Argentina, is validated.