Taxonomic contribution to knowledge of the oribatid mite genera Corynoppia, Ramusella and Wallworkella (Acari, Oribatida, Oppiidae)

Three new species of oribatid mites (Oribatida) of the family Oppiidae are described, based on adults collected during the dry season from the forest mineral soils in the Gamo Zone, South Ethiopia Regional State, southern Ethiopia. Corynoppia gamoensis sp. nov. (Mystroppiinae) differs from the related species C. weigmanni by the morphology of the adanal seta ad2, the morphology and location of the notogastral seta c, the number of the interbothridial muscle sigillae, and the absence of the cerotegumental bands. Ramusella (Insculptoppia) arbaminchensis sp. nov. (Multioppiinae) differs from the related species R. (I.) rybalovi by the morphology of the bothridial seta, the absence of the transcostula, postbothridial tubercle and prodorsal lateral ridge, and in the presence of a tooth on lateral carina in the podosomal region. Wallworkella southensis sp. nov. (Arcoppiinae) differs from the related species W. tetraciliata by the body size, the indistinct costular-transcostular complex, the relative length of some prodorsal setae, the morphology of anterior margin of the notogaster, and the length of the dorsal notogastral setae. A new synonymy is proposed: Wallworkella Balogh, 1983 (=Wallworkoppia Subas, 1989 syn. nov.). The detailed generic diagnoses for Corynoppia and Wallworkella are presented. Subgeneric placement of some species within Ramusella is discussed. Identification keys to the known species of Corynoppia and Wallworkella are given.