Life histories and host plants of the genus Asphondylia (Diptera; Cecidomyiidae) in Japan

Abstract

About 200 nominal species of the genus Asphondylia have been recognized in the world (HARRIS, 1975). They are morphologically quite similar, and species identifications are therefore based almost entirely on host data (HARRIS, 1975). In Japan only 4 species of the genus have been named, and some others have been left unnamed to avoid further confusion in nomenclature because their life history and host range have not been extensively investigated. This paper is intended to present information concerning their life history and host range for better understanding of taxonomic and ecological relationships among them. The information was mainly obtained by occasional field investigations and by rearing or dissecting midge galls collected from various parts of Japan between 1968 and 1979. The life history and host range of some univoltine species have been relatively well clarified (YUKAWA and MIYAMOTO, 1979), but those of multivoltine species, including such a serious pest as the soybean pod gall midge, have been only partly known, particularly the host plants of the overwintering generation have not been discovered. In order to clarify the biology of the multivoltine species and to establish their species identifications, it is emphasized that not only the high degree of host specificity being assumed to operate in most gall-making Cecidomyiidae but also the possibility that a gall midge has an unusually wide host range as has been noted in the carob midge complex (ORPHANIDES, 1975) should be taken into consideration.