Infestation of defaecated seeds by Coccotrypes dactyliperda (Coleoptera: Curculionidae: Scolytinae) and its implications on the dispersal success of palms

Abstract

ABSTRACT Numerous vertebrate species ingest palm drupes and disperse the seed by defaecation. Some insect species will predate seeds in animal scats, while others avoid them. This study examined the behaviour of date stone beetles (Coccotrypes dactyliperda) and found that the species ignored seeds coated with excreta but penetrated uncoated seeds. A case is made that the coating provides a physical barrier that prevents the kairomones from dispersing. With a lesser risk of predation by spermatophagus beetles and a greater chance of germination due to scarification in the gastrointestinal tract, vertebrate defaecated palm seeds have a much greater dispersal success that non-defaecated seeds.