Two new species of Gondwanaspis (Trilobita, Odontopleurida) from the Givetian-Frasnian transition of the northern Rhenish Massif (Germany)

The cosmopolitan genus Gondwanaspis is one of two post-Taghanic (late Givetian to Frasnian) odontopleurid genera and the only genus of the Odontopleurida surviving the Lower Kellwasser Event, finally disappearing at the Upper Kellwasser Event. Although it is known from the Frasnian of Australia, Germany, France, Morocco, and Russia, findings of the genus are comparatively rare. Here we present Gondwanaspis eisbornensis n. sp. from the probable lower Frasnian of the Beul section near Eisborn (northern Sauerland) and Gondwanaspis schloesseri n. sp. from possibly top-Givetian strata of the Hofermühle South Quarry of the Bergisches Land (Velbert Anticline), both in the northern Rhenish Massif. Gondwanaspis schloesseri n. sp. represents one of the few species of which both the cephalon and pygidium are known, while the holotype of G. eisbornensis n. sp. is one of the largest known specimens within the genus.