Species:
Retusa obtusa >
Genus:
Retusa >
Family:
Retusidae >
Superfamily:
Bulloidea >
Order:
Cephalaspidea >
Subterclass:
Tectipleura >
Infraclass:
Euthyneura >
Subclass:
Heterobranchia >
Class:
Gastropoda >
Phylum:
Mollusca >
Kingdom:
Animalia >
Unranked:
Biota >