Conulus castaneus plana Popiel-Barczyk, 1958 † accepted as Conulus rothomagensis (Sismonda, 1844) † (original description)
Conulus castaneus rhotomagensis † accepted as Conulus castaneus rothomagensis (Sismonda, 1844) † accepted as Conulus rothomagensis (Sismonda, 1844) † (basis of record)
Conulus castaneus var. plana Popiel-Barczyk, 1958 † accepted as Conulus castaneus plana Popiel-Barczyk, 1958 † accepted as Conulus rothomagensis (Sismonda, 1844) † (original description)
Conulus castaneus var. rhotomagensis Agassiz in Popiel-Barczyk, 1958 † accepted as Conulus castaneus rothomagensis (Sismonda, 1844) † accepted as Conulus rothomagensis (Sismonda, 1844) † (additional source)
Conulus ellipticus rostrata Popiel-Barczyk, 1958 † accepted as Conulus mixtus (Defrance, 1820) † (original description)
Conulus ellipticus var. rostrata Popiel-Barczyk, 1958 † accepted as Conulus ellipticus rostrata Popiel-Barczyk, 1958 † accepted as Conulus mixtus (Defrance, 1820) † (original description)
Conulus subrotundus subglobosa Popiel-Barczyk, 1958 † (original description)
Conulus subrotundus var. subglobosa Popiel-Barczyk, 1958 † accepted as Conulus subrotundus subglobosa Popiel-Barczyk, 1958 † (original description)
Conulus subtrotundus conoidea Popiel-Barczyk, 1958 † (original description)
Conulus subtrotundus var. conoidea Popiel-Barczyk, 1958 † accepted as Conulus subtrotundus conoidea Popiel-Barczyk, 1958 † (original description)