Pterygotus anglicus Agassiz (Chelicerata: Eurypterida) from Atholville, Lower Devonian Campbellton Formation, New Brunswick, Canada

Specimens of the large eurypterid Pterygotus from the Early Devonian Campbellton Formation outcropping at Atholville, New Brunswick, are identified as Pterygotus anglicus Agassiz. The locality, in the Atholville beds near the western end of the Campbellton Formation exposure, is best known for its vertebrate fauna of ostracoderms, arthrodires, acanthodians and chondrichthyans, first described in 1881. Although a significant series of pterygotid fossils was acquired by the Natural History Museum, London, in 1892, it received little attention. A few small specimens from the Geological Survey of Canada collections were named Pterygotus atlanticus by Clarke and Ruedemann, considered here to be an invalid taxon. They suggested that P. atlanticus might turn out to be a small specimen of P. anglicus. The new material described here, including one relatively complete individual, confirms their suspicions and provides evidence of Pterygotus anglicus in the Lower Devonian of North America.