The North American flatid planthopper Metcalfa pruinosa (Say) (Hemiptera: Flatidae), which has spread throughout much of southern Europe since its introduction some thirty years ago, has been the focus of a number of morphological, ecological, and behavioral studies (Alma, 2000; Wilson and Lucchi, 2000, 2001; Lucchi and Mazzoni, 2004). In Europe, this insect can reach high densities on a variety of economically important woody plants. These planthoppers feed by sucking phloem sap and produce copious amounts of honeydew because they lack a filter chamber and have a midgut cellular membrane which prevents the efficient uptake of sugars (Lucchi et al., 1999). Honeybees (Apis mellifera L.) (Hymenoptera: Apidae) collect honeydew produced by M. pruinosa and utilize it to manufacture honey (Lucchi, 1997). This honey is harvested by apiarists in Italy and southern France and marketed as ‘‘Meile di Melata di Metcalfa’’ (5Metcalfa honey) (Lucchi, 2000). Field observations indicate that honeybees collect most of the honeydew in the early morning and at sunset (Barbattini et al., 1997). This restriction of honeybee activity to these times is likely due to the relative availability of honeydew and the fact that honeydew dries quickly during the heat of the day. In the present study we detailed the feeding activity schedules of fifth instar nymphs and adults of M. pruinosa by measuring honeydew production.