Apium nodiflorum subsp. submersum (Glück) Thell. Dataset GBIF Backbone Taxonomy Rank SUBSPECIES Classification kingdom Plantae phylum Tracheophyta class Magnoliopsida order Apiales family Apiaceae genus Helosciadium species Helosciadium nodiflorum Name Homonyms Apium nodiflorum f. submersum (Glück) Thell. Apium nodiflorum subsp. submersum (Glück) Thell.