Barbula subrivicola subsp. densifolia P.C.Chen Dataset GBIF Backbone Taxonomy Rank SUBSPECIES Classification kingdom Plantae phylum Bryophyta class Bryopsida order Pottiales family Pottiaceae genus Didymodon species Didymodon nigrescens Name Homonyms Barbula subrivicola var. densifolia P.C.Chen Barbula subrivicola subsp. densifolia P.C.Chen