Penetration of Phoenix canariensis drupes by the date stone beetle Coccotrypes dactyliperda (Coleoptera, Curculionidae, Scolytinae)

Abstract

Date stone beetles (Coccotrypes dactyliperda Fabricius, 1801) tunnel into palm seeds to establish brood galleries with their larvae consuming the seed’s albumen. Prior work examining the location of the initial penetration holes in de-fleshed seeds had shown a preference for the dorsal groove. This paper presents the data of a follow-up experiment that examined the preferences for penetration holes on complete drupes. Using 100 repeats of a single freshly harvested drupe offered to a single beetle, the study found an overwhelming preference for the beetles to penetrate the drupe at the pedicel scar, with all other sectors significantly less utilised. The implications of this are discussed.

Keywords

• spermatophagy
• feeding behavior
• locomotion
• activity patterns
• palmae
• insect biology