Studies on the dung-breeding flies in Japan : IV The immature stages of three muscine species occurring from wild brown bear dung (Diptera : Muscidae, Muscinae)

Abstract

The immature stages of three muscine species, Pyrellia tateyamensis Shinonaga, Mesembrina resplendens Wahlberg and Huckettomyia watanabei Pont et Shinonaga, occurring from wild brown bear dung were newly described and their characteristics of taxonomic and biological significance were discussed. The third instar larva of P. tateyamensis was of typical Muscini-type, and can be distinguished from those of the known Dasyphora-larva in having a pair of extraanal papillae. This larva also differs from that of P. cadaverina (Linnaeus) in the characteristics of posterior spiracles. The larval mode of life of M. resplendens was trimorphic obligatory coprophagous. The third instar larva of resplendens is partially related to those of Hydrotaeini and Phaoniinae-Mydaeinae, and can be distinguished from that of a Palaearctic species, M. meridiana Linnaeus in having doubled number of branches on anterior spiracles and by the characteristics of posterior spiracles, but extremely resemble that of M. mystacea Linnaeus described from Russia. Egg of H. watanabei was of typical muscine-type, but the larval characteristics have a close relationship to those of Phaoniinae and Mydaeinae. The third instar larva of this species seems to be facultative carnivorous.