Supra-anal Organ: a Defensive Mechanism of the Furniture Carpet Beetle, Anthrenus flavipes (Coleoptera: Dermestidae)1

Abstract

Larvae of the furniture carpet beetle, Anthrenus flavipes LeConte, possess a bundle of caudal spicisetae kept in constant vibration during locomotion. These setae originate from an elliptical cuticular plate situated at the upper middle portion of the last larval segment above the anus. This “supra-anal organ” occurs in all larval instars, and the number of associated spicisetae is specific for each instar. These vibrating caudal setae contribute to the overall defense of the larva against the attacks of both a pseudoscorpion predator, Chelifer sp., and a bethylid parasite, Laelius pedatus (Say).