England, the site of the initial discovery of "P. problematicus", has provided fossils for several additional species. Kjellesvig-Waering named three new species from England in 1961; "P. denticulatus", "P. lightbodyi" (both Late Ludlow in age) and "P. grandidentatus" (Wenlock, Late Silurian, in age). "P. denticulatus" is known from a single specimen (No. 48393 of the British Museum of Natural History) includes about half of the anterior end of what is presumed to be a fixed ramus of a chelicera. The claw is stout, with unusually short teeth that are faintly ribbed. This partial ramus measures 1.4 cm (0.5 in) in length and was discovered at Whitcliffe in Shropshire, England associated with fossils of brachiopods and cephalopods. Though it is sometimes considered synonymous with "P. lightbodyi", "P. denticulatus" can be distinguished by the small, thick and curved teeth of its claws, differing not only from "P. lightbodyi" in this respect, but virtually all other species of "Pterygotus" as well.