In the Silurian deposits of the Temeside Shale, England, where the type species has been discovered, fossils of several organisms have been found, most of them eurypterids such as "Erettopterus gigas", "Salteropterus abbreviatus" and "Nanahughmilleria pygmaea", but also indeterminate species of the osteostracid "Hemicyclaspis" and the thelodontid "Logania". "Parahughmilleria" fossils have also been discovered in the United States, Russia, Luxembourg, Canada and Scotland.