Two new actinedid mites are described from the gravel plain of the Namib desert : Namibarbutia seelyae n. gen., n. sp. (Barbutiidae) and Linotetranus mirabebensis n. sp. (Linotetranidae). The definitions of the genus Barbutia and the family Barbutiidae are modified accordingly. Identification keys are provided for both families. The high value of the ratio length-width of the new species is related to habitat.