| phylogeography of helleria brevicornis (crustacea, oniscidea): old and recent differentiations of an ancient lineage. | helleria brevicornis has a disjunct, peri-tyrrhenian distribution that mirrors that of several organisms, for which geographic vicariance is invoked, due to the geological events started with the oligocene split of the sardo-corsican microplate from the pyrenees, and successive separation between sardinia and corsica. molecular phylogenetic analyses demonstrated that such a biogeographic model does not apply to helleria. the original split of the sardinian and corsican lineages originated in the ... | 2010 | 19853050 |