Douvilleiceras mamillatum aequinodus Quensted, 1846 Dataset GBIF Backbone Taxonomy Rank SUBSPECIES Classification kingdom Animalia phylum Mollusca class Cephalopoda family Douvilleiceratidae genus Douvilleiceras species Douvilleiceras mammillatum Name Homonyms Douvilleiceras mamillatum aequinodus Quensted, 1846