Rissoa membranacea gracilis (Forbes & Hanley, 1850) Dataset GBIF Backbone Taxonomy Rank SUBSPECIES Classification kingdom Animalia phylum Mollusca class Gastropoda order Littorinimorpha family Rissoidae genus Rissoa species Rissoa membranacea Name Homonyms Rissoa membranacea gracilis (Forbes & Hanley, 1850) Rissoa membranacea var. gracilis (Forbes & Hanley, 1850)