Biological Insights on the Invasive Fig Pest Aclees taiwanensis Kȏno, 1933 (Coleoptera: Curculionidae)

Abstract

The fig weevil Aclees taiwanensis Kȏno, 1933 (Coleoptera: Curculionidae) is an invasive fig tree pest recently introduced in southern Europe. Reported for the first time in France in 1997 as A. cribratus, and then in Italy in 2005 as A. sp. cf. foveatus, A. taiwanensis is currently threatening fig nurseries, orchards, and wild plants. To date, no control methods have proven to be effective against A. taiwanensis. Although some attempts have been made to describe the insect’s biology and behavior, such information is limited to that obtained from adult samples collected in the field. In particular, because of their xylophagous behavior, scarce information is available on the larval stages of the species. The aim of this study, therefore, was to fill these information gaps on the insect biology and behavior by setting up a laboratory protocol suitable for the rearing of A. taiwanensis. Using the developed rearing protocol, we assessed the main fitness parameters of the species including oviposition rate, egg hatchability, embryonic, larval and pupal duration and development, immature survival, pupation behavior, pupal weight, emergence, sex ratio and adult morphological parameters. The proposed rearing procedure allowed us to obtain new information on the main features of the insect’s biology that may be useful for setting up strategies for its control.