New arthropods from the Lower Devonian Hunsru¨ck Slate (Lower Emsian, Rhenish Massif, western Germany)

Four new genera and species of arthropod, Cambronatus brasseli Wingertshellicus backesi Eschenbachiellus wuttkensis and Magnoculus blindi , are described from the Hunsru¨ck Slate (Lower Emsian) of Germany. All four occur in the Wingertshell Member in the vicinity of Bundenbach. They preserve remarkable details of the ventral morphology, including the appendages, as a result of pyritization. In each case the body consists of just two tagmata, a cephalon and a large number of similar trunk somites. Both Cambronatus Wingertshellicus have fluke-like appendages making up a tail fan. The affinities of these arthropods lie with the Crustacea, apart from Magnoculus , which is an arachnomorph, but they do not fall within those clades with modern representatives. They show that morphologies other than those represented by trilobites and modern arthropod groups persisted long after the Cambrian, at least in muddy bottom marine settings.