You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Phylogeny of Isoëtes (Lycopsida): Resolving Basal Relationships Using rbcL Sequences
Catarina Rydin and Niklas Wikström
Vol. 51, No. 1 (Feb., 2002), pp. 83-89
Published by: International Association for Plant Taxonomy (IAPT)
Stable URL: http://www.jstor.org/stable/1554965
Page Count: 7
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
The phylogenetic relationships of Isoëtes (Isoëtaceae) were investigated by means of a cladistic analysis using plastid rbcL sequences and a representative sample of 18 species. The analysis supports a basal split in Isoëtes separating two main groups, one including aquatic species from South America (I. bradei and I. amazonica) and West Africa (I. kersii and I. schweinfurthii), and the other including aquatic, amphibious and terrestrial species representing all major continents. Higher level relationships remain unresolved, but supported groups do conflict with previous morphology-based hypotheses. Comparatively low levels of sequence divergence indicate that the use of more rapidly evolving regions will be required to resolve higher level relationships. The phylogenetically isolated nature of Isoëtes will in such analyses make standard outgroup comparisons problematic, and results presented here will in this respect prove important by providing support for choosing among alternative rooting options.
Taxon © 2002 International Association for Plant Taxonomy (IAPT)