Arthropod Phoresy Involving Pseudoscorpions in the Past and Present

Pseudoscorpions form phoretic associations with a wide range of arthropods, including at least 44 families of insects and three families of arachnids. The present work brings up to date phoretic associations between pseudoscorpions and different arthropods and discusses the long-standing controversy over whether this behavior is basically a predatory response or adapted solely for dispersal. That phoresy in pseudoscorpions is of long standing and obligatory in many cases is demonstrated by its continuance for millions of years, as shown by the fossil record. A member of the Chthoniidae attached to a moth in Baltic amber is reported for the first time.