Development and validation of a simplified morphological identification key for larvae of tephritid species most commonly intercepted at import in Europe

Abstract

Fruit flies (Diptera, Tephritidae) are amongst the most important pests on fruits and vegetables worldwide. All non‐European Tephritidae are listed in Annex I/A1 of Directive 2000/29/EC but only a limited number of species are regularly intercepted in Europe. This study presents a morphological identification key, supported by molecular analysis, for the third‐instar larvae of 10 commonly intercepted taxa. The key proved to be sensitive and specific. However, the evaluation of its reproducibility emphasizes the importance of the operator's taxonomic expertise and questions the relevance of criteria under which a morphological method can be validated. This morphological identification key provides a rapid and economic diagnostic tool for identifying tephritid larvae. It is not intended to cover all species but allows for an initial diagnosis to be made. Given the current difficulty in identifying most immature stages of insects, the approach presented here could be used to develop some morphological identification tools for other species of concern.