 Shells of "Protetragonites" species reach a diameter of about .Shells show few constrictions and a circular or triangular section.Fossils of species within this genus have been found in the Cretaceous rocks of Austria, Canada, Czech Republic, Slovakia, Dominican Republic, France, Hungary, Madagascar, Morocco, Poland, Spain, Russia, Ukraine, Western Sahara, as well in the Jurassic of Germany, Hungary and Italy.