Polla horna (Hedw.) Brid. Dataset GBIF Backbone Taxonomy Rank SPECIES Classification kingdom Plantae phylum Bryophyta class Bryopsida order Bryales family Mniaceae genus Mnium species Mnium hornum Name Homonyms Polla horna (Hedw.) Brid. ex Loeske Polla horna (Hedw.) Brid.