PREIMAGINAL DEVELOPMENT OF LARVAE OF THE GROUND BEETLE SPECIES POECILUS-CUPREUS IN RELATION TO SOIL HUMIDITY AND TEMPERATURE (COLEOPTERA, CARABIDAE)

The influence of different soil-humidities and temperatures on the lar val development of the carabid beetle Poecilus cupreus (Linnaeus 1758) was investigated. Eclosion rate, weight of newly eclosed imagines and duration of development from 1st larval instar to imago were recorded . The larvae did not survive if the soil was at 60% of its water capac ity or more. With 50% saturation, the eclosion rate was only 10%. High est values were obtained at 15-20% of the water capacity. Imaginal wei ght and duration of development were not much influenced by the water content of the soil. Temperature (tested range: 17-degrees-C-25-degree s-C;) had no effect on the eclosion-rate but if it was raised from 17- degrees-C-25-degrees-C, the duration of development was reduced from 5 3-29 d, and the imaginal weight was slightly lowered.