The setae on the anal valves belong to segment PS. Spider mites have 1–2 pairs of these ps setae:
Two pairs of anal setae are present in Eutetranychus, Schizotetranychus, Eotetranychus, Panonychus, Allonychus, Amphitetranychus, Tetranychus, and Oligonychus.
In Aponychus only 1 pair of anal setae is present.

