| abstract | A new myobiid mite species Radfordia (Hesperomyobia) akodon sp. nov. is described from Akodon varius Thomas (Rodentia: Cricetidae: Sigmodontinae) from Bolivia. This new species is known only from a female which differs from those of Radfordia (H.) sigmodontis Radford from Sigmodon hispidus Ray and Ord, and Radfordia (H.) sigmomys Bochkov and Fain from Sigmodon alstoni (Thomas) by the following features. In R. (H.) akodon sp. nov., setae vi are 50 µm long and 7 µm wide (vs. 10–12 µm long and 2 µm wide in R. sigmodontis, and 23–25 µm long and 2 µm wide in R. sigmomys), dorsal idiosomal setae si, se, c1, c2, d1, and d2 are 5–10 µm wide (vs. 2–3 µm wide in R. sigmodontis and R. sigmomys), and setae e1 are 2.6 times longer than f1 (vs. subequal in R. sigmodontis and R. sigmomys). In addition, Radfordia (Hesperomyobia) vandenberghi Fain and Lukoschus is newly recorded herein from Oligoryzomys flavescens (Waterhouse) and Oligoryzomys sp. (Rodentia: Cricetidae: Sigmodontinae) in Bolivia. It is suggested that this mite species is associated exclusively with hosts of the genus Oligoryzomys Bangs. |