The Greek word sphyrna translates as hammer, referring to the shape of this shark's head - tiburo is the Taino word for shark.
The sediments that have yielded Pelagiarctos have also yielded numerous other species of ocean-going vertebrates, including sharks (Isurus, Sphyrna, Carcharocles), turtles (Psephophorus), seabirds (Osteodontornis, Diomedea, Puffinus), Cetaceans (Prosqualodon, Aulophyseter, Parietobalaena) and other pinnipeds (Allodesmus, Neotherium).