protoctista: in most modern classifications, replacement for the Protista; includes: Protozoa; Euglenophyta; Chlorophyta; Cryptophyta; Heterokontophyta; Rhodophyta; unicellular protists and their descendant multicellular organisms: regarded as distinct from plants and animals
taxonomic group: animal or plant group having natural relations
urgency: the state of being urgent; an earnest and insistent necessity