During the field study of eriophyoid mites from Clematis orientalis L. (Ranunculaceae) in semi-arid and arid environment in East Iran (Birjand, South Khorasan, Iran, from 2016 to 2017), two new eriophyid mite species (Trombidiformes: Eriophyidae) were collected. They are Epitrimerus birjandicasp. nov. and Aculus clemachinensissp. nov.; they are illustrated and described herein. Both new species seemed to be vagrants on the green parts. The checklist of eriophyid mites associated with Ranunculaceae throughout the world was provided.