Can Cuticular Hydrocarbons Be used as Chemotaxonomic Tool for Neosilba McAlpine (Diptera: Lonchaeidae)?

Recent studies have shown an interest in the Neosilba McAlpine (Diptera: Lonchaeidae) genus, as its larvae are reported to feed on many commercially relevant fruits. However, the taxonomical difficulty to identify the species of this genus apart ends up hampering and discouraging research on these flies. In this work, cuticular hydrocarbons were extracted, identified, and evaluated as chemotaxonomic characters from six species of adult Neosilba lance flies. We also investigated whether the fruits used by these flies as larval nutrition substrates influence the cuticular hydrocarbon profiles expressed by these flies. Forty-one hydrocarbon components were identified by gas chromatography-mass spectrometry. The components represented four classes: n-alkanes, monomethyl alkanes, dimethyl alkanes and alkenes. Cuticular hydrocarbon analysis does not provide a reliable method to differentiate Neosilba species. The CHC components were overall common but the blend ratios differed even within Neosilba species. Cuticular hydrocarbon mixtures show host fruit-associated variation. The expression of cuticular hydrocarbons dependent on host fruit found in this study may suggest the formation of host race.