Computed Microtomography of the Third Instar Larva of the Eastern Fruit Fly Bactrocera dorsalis (Hendel, 1912) (Diptera, Tephritidae), with New Data on Morphological Characters of Fruit Fly Larvae Useful for Species Diagnostics

Abstract

The muscular system of the larva of the eastern fruit fly Bactrocera dorsalis (Hendel, 1912) (Diptera, Tephritidae), a quarantine pest of many fruit crops, was studied by X-ray computed microtomography (micro-CT). The larval muscles of Bactrocera dorsalis were compared with those of Drosophila melanogaster Meigen, 1830 (Diptera, Drosophilidae), since the latter is the most thoroughly studied larva among the Diptera Cyclorrhapha. Although the two species belong to different unrelated families, they were found to possess similar sets of muscles, differing largely in places of attachment and degree of development. The more strongly developed muscles associated with the cephaloskeleton and mouth hooks in Bactrocera dorsalis as compared with Drosophila melanogaster may be related to the different density of their substrates: the larvae of Bactrocera dorsalis make tunnels in fruit tissues and (before pupation) in soil, while those of Drosophila melanogaster develop in decaying substrates.