CORRELATED RESPONSE OF NYMPHAL PERIOD TO SELECTION FOR WING FORMS IN THE PYRRHOCORID BUG, PYRRHOCORIS-SIBIRICUS (HETEROPTERA, PYRRHOCORIDAE)

The pyrrhocorid bug, Pyrrhocoris sibiricus, which is a ground-dwelling seedfeeder, shows wing polymorphism producing brachyptery and macropt ery. This study was undertaken to investigate nymphal periods of the t wo wing morphs, which were derived from two lines artificially selecte d for different wing forms, at 20 degrees C and 30 degrees C under 12L -12D. No macropters appeared from either selected line at 20 degrees C . At 30 degrees C, however, only the macropterous-selected line produc ed macropters. Nymphal period of brachypters was longer in the macropt erous-selected line than in the brachypterous-selected line. This resu lt suggests that the selection for wing form affects not only wing for m but also nymphal period. No significant difference in the nymphal pe riod was shown between the two wing morphs in the macropterous-selecte d line at 30 degrees C.