World species of the subgenus Oligonychus (Reckiella) Tuttle and Baker (Acari, Prostigmata, Tetranychidae), diagnostic keys, taxonomic notes, and a new species

Oligonychus Berlese (Acari, Prostigmata, Tetranychidae) is an agriculturally important and the largest genus of spider mites, comprised of 211 species (including new species), two subgenera, four species groups, and 11 species subgroups. The present study comprehensively addressed the morphotaxonomic-based identification of world species of the subgenus Reckiella Tuttle and Baker. Five diagnostic keys were developed for identifying Oligonychus (Reckiella) species belonging to five species subgroups: iseilemae, pritchardi, biharensis, gossypii, and exsiccator. Taxonomic notes are provided on intraspecific variations and some closely related Oligonychus (Reckiella) species representing six species complexes, viz. the afrasiaticus complex, the litchii complex, the pratensis complex, the plegas complex, the sacchari complex, and the tylus complex. One new spider mite species, Oligonychus bahaensis sp. nov., is described and illustrated from Grasses (Poaceae) under the subgenus Reckiella.