Kingdom Protozoa Goldfuss, 1818 - protozoa Subkingdom Corticata Lankester, 1878 see Subkingdom Biciliata Infrakingdom Excavata T. Cavalier-Smith, 2002 see Supergroup Excavata Cavalier-Smith, 2002 Superphylum Archezoa Cavalier-Smith, 1983 see Infrakingdom Archezoa Cavalier-Smith, 1983 Phylum Metamonada Grassé, 1952 Genus Giardia Künstler, 1882 Giardia intestinalis