Abstract
Unionicola (Iridinicola) botswaniana n. subgen., n. sp. (Hydrachnida: Unionicolidae) is described from freshwater mussels, Mutela zambesiensis and Aspatharia pfeifferiana, from Okavango River, Botswana, Africa. The new species is a unique mite with distinctive female genital field anatomy and leg chaetotaxy. This new mite extends our understanding of the morphology and biogeography of the genus in Africa. It further extends our knowledge of host selection and host-specificity among African Unionicola.