|Abstract||This paper deals with Australian Unionicola species, collected from all over the continent. Two new subgenera are
described, Vidrineatax new subgen. and Geikienicola new subgen., as well as eight new species: U. (Kovietstax) crassiseta n. sp., U. (Downesatax) curvipalpis n. sp., U. (Geikienicola) insolita n. sp., U. (Downesatax) latiseta n.sp., U. (Downesatax) longipalpis n. sp., U. (Vidrineatax) pilosa n. sp., U. (Giselatax) trisetica n. sp. and U. (Giselatax) uncatiseta n. sp. The subgenus Smithatax is synonymised under the subgenus Downesatax. Thus 11 of the now 56 subgenera in the genus Unionicola are known from Australia. Furthermore, the first description is given of the female of U. flabelliseta Cook. Additional data are provided for U. cirrosa Koenike. Many new records are presented, especially for the Northern Territory and Western Australia.