| The biodiversity of freshwater littoral zone microcrustaceans is poorly known outside of Europe. The toxicological model Simocephalus (Daphniidae), for example, is common on every continent, but has an unknown or controversial regional diversity. Here I present the first molecular phylogenies (nuclear and mitochondrial DNA) of Simocephalus and directly compare New World specimens to type regions in Europe. I aimed to test the hypothesis of cosmopolitanism in S. vetulus. I revise the taxonomy in consideration of the several hidden, and apparently ancient, regional clades. The results have implications for the comparative toxicology of this microcrustacean. |
