Feeding and oviposition of Haemaphysalis flava females (Acari : Ixodidae) exposed to different photoperiods, with special reference to morphogenetic diapause

Abstract

In order to clarify whether or not engorged Haemaphysalis flava females exhibit morphogenetic diapause, their feeding and oviposition were observed at 24℃ under three photoperiodic conditions (10L-14D, 12L-12D, and 16L-8D). The feeding period was hardly affected by the different photoperiods. However, the oviposition was retarded by exposure to the 10L-14D photoperiod and partly by the 12L-12D photoperiod. These results suggest that engorged H. flava females enter morphogenetic diapause under medium-day and short-day photoperiods. Thus, most of the H. flava females that are active in the short days of autumn appear to enter morphogenetic diapause and eventually hibernate in the engorged state.