In a recent publication, Zhang, Fu and Wang (2004) reported a karyotype analysis of two species of brachypyline oribatid mites: Brasilobates spinosus Fujita (Protoribatidae, or Haplozetidae) and Galumna longiporosa Choi (Galumnidae). After studying what they referred to as oocytes, the authors concluded that both species have an XX:XO sex determining mechanism and that the karyotype is 2n=16 for male B. spinosus and 2n=19 for male G. longiporosa. Chromosomes were reported to be monocentric. However, we believe that some of the applied methods and interpretations are questionable, and the authors overlooked important past studies of oribatid mite karyology. Our purpose is to briefly discuss these issues and to highlight the rather dramatic contradictions with published literature. As an example, we present the first data on the karyotype of Archegozetes longisetosus Aoki (Trhypochthoniidae), and discuss why the conclusions of Zhang et al. cannot represent the general state of cytogenetics in Oribatida.