Bioacoustics of Trogoderma granarium Everts (Coleoptera: Dermestidae)

Abstract

Trogoderma granarium Everts (Coleoptera: Dermestidae) is one of the major destructive pests of grain products in hot and dry parts of the world. No information has been made available on the bioacoustic signals (BASs) of T. granarium. In this paper, the bioacoustic features of this insect have measured from larvae and adult males and females. No anechoic chamber was used in this study. The extracted features were compared to evaluate the ability of the acoustic method to determine larva or adult as well as their sex. Adult males and females and larvae T. granarium produced BASs with a length of 2–11, 2–52, and 2–30 ms with a maximum sound pressure level of 3, 36, and 17 dB, respectively. At least 60 % of all BASs were in the ranges of 2–12 impulses in larva and adult stages. The sum of the total BASs was different in larvae and adult stages. Adult males had the least number of BASs compared to adult females and larvae. Detection of the growth stage and determination of the sex of the adult T. granarium by acoustic method in the time domain depends on the feature extracted from BASs and number of their impulses. Furthermore, in the frequency domain, the most dominant frequency bands were in the range of 1–8 kHz. In this band, the most dominant frequency band was 3.5–4.5 and 1–1.7 kHz for adult males and larvae, respectively. The most dominant bands of 1–3 and 4–5 kHz were observed for adult females.