Contribution to the knowledge of the oribatid mite genus Perxylobates (Acari, Oribatida, Haplozetidae)

Perxylobates hakkai n. sp. (Oribatida, Haplozetidae) is the second representative of the genus recorded in Taiwan; it is described based on adults from soil under Ricinus communis on a farm of the Agricultural Research and Extension Station in Miaoli District. The new species differs from related Perxylobates coreanus Choi and Aoki, 1993 by the presence of five pairs of genital setae (versus four pairs), four pairs of notogastral porose areas including A3 (versus three pairs, A3 absent), minute epimeral seta 1c (versus comparatively long), roughened epimeral and aggenital setae (versus heavily barbed), and smooth anterior part of prodorsum (versus foveolate). A revised generic diagnosis and an identification key to known species of Perxylobates are provided. The systematic placement of Perxylobates mahunkai Bayoumi, 1980 is discussed, resulting in the following new taxonomic proposal: Protoribates mahunkai (Bayoumi, 1980) n. comb.