We describe 16 new species and redescribe six established species in the genus Raoiella-R. argenta sp. nov. Beard, R. australica Womersley, R. bauchani sp. nov. Beard Ochoa, R. calgoa sp. nov. Beard Ochoa, R. crebra sp. nov. Beard Ochoa, R. davisi sp. nov. Beard, R. didcota sp. nov. Beard, R. eugeniae (Mohanasundaram), R. goyderi sp. nov. Ochoa Beard, R. hallingi sp. nov. Beard, R. illyarrie sp. nov. Beard Ochoa, R. indica Hirst, R. karri sp. nov. Ochoa Beard, R. macfarlanei Pritchard Baker, R. marri sp. nov. Beard Ochoa, R. pandanae Mohanasundaram, R. pooleyi sp. nov. Beard Ochoa, R. shimpana Meyer, R. tallerack sp. nov. Beard Ochoa, R. taronga sp. nov. Beard Ochoa, R. todtiana sp. nov. Beard Ochoa, R. wandoo sp. nov. Beard Ochoa. We discuss molecular evidence of species separation, shared character states among groups of species, and patterns in the additions of leg setae throughout ontogeny that occur in the genus. We provide a key to the known species of Raoiella.
Keywords: Acari, Angophora, coconut, Corymbia, endemic, Ericaceae, Eucalyptus, false spider mite, flat mite, Lophostemon, molecular analysis, Myrtaceae, Neoraoiella, Pandanus, Rarosiella, red palm mite.