Sea scorpions (Chelicerata, Eurypterida) from the Lower Devonian (Siegenian) of the Lahrbach Valley/Westerwald area (SW Germany, Rhineland-Palatinate)

A Lower Devonian (Siegenian) eurypterid association from a particular mudstone layer in the Lahrbach Valley near Bürdenbach/Westerwald is described. It is dominated by a species of the adelophthalmoid Parahughmilleria. Based on the paddle morphology Eurypterus statzi Størmer, 1936 from the Siegenian of the Wahnbachtal is transferred here to Parahughmilleria as P. statzi n. comb. Despite being slightly older, the proportions of paddle segments in the Bürdenbach specimens more closely match those of P. hefteri from the Emsian of Alken. Therefore, they are tentatively assigned to this taxon but left in open nomenclature as P. cf. hefteri. Additional eurypterid remains probably represent adelophthalmoids as well, but are clearly distinguishable from Parahughmilleria. One specimen is comparatively well-preserved and deserves to be described and formally named here as Wiedopterus noctua n. gen. n. sp. In addition, rare remains of pterygotid eurypterids have been recorded.