Abstract
Larvae of the swift moth, Endoclita excrescens (Butler) were reared on an artificial diet under a long (16 : 8 h light/dark) or short (10 : 14 h light/dark) stationary photoperiod at 25°C. Larvae were also reared under different photoperiod conditions; second to ninth larval instars were transferred from a long photoperiod condition to a short photoperiod condition. The larvae sporadically pupated at low rates under long (20%) and short (7%) stationary photoperiods. By contrast, the larvae almost synchronously pupated at the highest rate (90%) when they were transferred from the long photoperiod to the short photoperiod at the ninth larval instar. These results show that the pupation of E. excrescens can be accelerated by transferring the larvae from a long photoperiod to a short photoperiod at the ninth larval instar. Adult emergence of E. excrescens in the field is, therefore, thought to occur from late summer to autumn.
