VISUAL TRAPPING OF THE STROBILOMYIA SPP (DIPT, ANTHOMYIIDAE) FLIES DAMAGING SIBERIAN LARCH CONES IN NORTH-EASTERN CHINA

The influence of trap position and colour on the response of the flies infesting Siberian larch cones was investigated in 1993 at two sites located in the Da Khinggan Mountains, in north-eastern China. A total of 339 flies were caught. Six Strobilomyia species were identified, an d 68.4% of them were females. S. svenssoni Mich. and an undescribed St robilomyia species were recorded for the first time in China as larch cone pests. Species- and sex-specific responses of flies to trap colou r and trap position were observed. For most species, the number of fli es alighting on blue traps hung within tree canopy was higher than tha t caught on yellow and yellow with purple striped traps placed in fron t of trees. Most flies trapped with blue were sexually-immature female s. The temporal succession of the six species and their oviposition pa tterns were related to the phenology of cone development. Five differe nt types of eggs were also described.